FIELD OF INVENTION

The field of the invention relates to lighting systems, preferably for outdoor lighting or industrial lighting. Particular embodiments relate to a lighting system powered inductively.

BACKGROUND

Domestic lighting system which are supplied in power via an inductive power supply device are well known but are not well adapted for uses requiring an installation with a stable fixation, such as in outdoor lighting or industrial lighting for example, due to the differences in constraints in terms of characteristics of the lighting provided in a demanding environment, or in terms of the infrastructure providing power. Typically, the inductive domestic lighting systems are developed based on aesthetical considerations and forego more practical considerations.

In particular, one of the aspects which is not transposable to a demanding environment from domestic lighting systems is the base support for the luminaire head. Indeed, the environment indoors is generally controlled and risk-free, while the environmental conditions are ever changing in an outdoor situation. Also, the sole purpose of domestic lighting systems is illumination. This situation must be remedied for when considering a lighting system powered inductively where fixation stability, adaptability, and multi-purpose use are parameters to take into account.

SUMMARY

The object of embodiment of the invention is to provide a lighting system, preferably for outdoor lighting or industrial lighting, powered inductively allowing for a modular and user-friendly installation, and with a stable support for the illumination. Such lighting system and inductive power supply device are advantageous for a number of applications, e.g. temporary lighting, events lighting, modular lighting, and environments, e.g. outdoor environment, industry halls, warehouses, construction sites. Additionally, it would be advantageous to obtain a multi-purpose inductive lighting system to adapt to different uses.

According to a first aspect of the invention, there is provided a lighting system, preferably for outdoor lighting or industrial lighting. The lighting system comprises a power supply and a plurality of inductive modules. The power supply is configured for generating electrical power provided to a primary wire forming a current loop. The plurality of inductive modules is configured for receiving power from the power supply. Each of the plurality of inductive modules includes an electromagnetic coupling means and a functional unit. The electromagnetic coupling means comprises a magnetic core configured for receiving the current loop of the primary wire, and a secondary wire wound around a portion of the magnetic core and configured for coupling inductively to the primary wire. The functional unit is connected to the secondary wire. The electromagnetic coupling means is configured for providing current to the functional unit. At least one inductive module of the plurality of inductive modules comprises a functional unit corresponding to a lighting unit with at least one light source, preferably at least one light emitting diode. Each of the plurality of inductive modules further comprises a housing configured for at least partially enclosing the electromagnetic coupling means, said housing being provided with a through-hole corresponding to a central hole of the magnetic core. The lighting system further comprises an envelope configured for receiving the primary wire therein, said envelope configured for extending through the through-hole of the housing. After arranging the plurality of inductive modules onto the envelope of the power supply, the envelope supports the plurality of inductive modules.

The skilled person will understand that an inductive functional system may be implemented similarly as described above with none of the plurality of inductive modules comprising a lighting unit.

In the lighting system according to the invention, the power supply provides AC power to the primary wire. The plurality of inductive modules receives the AC power from the primary wire via the secondary wire due to the electromagnetic induction phenomenon using the magnetic core of the electromagnetic means.

Since the power is supplied to the plurality of inductive modules using the electromagnetic induction phenomenon, there is no need for a physical coupling between the power supply and the plurality of inductive modules using wires for example. Thus, the plurality of inductive modules may be easily installed and positioned without complex electrical wiring required. It contributes to a high modularity of the system in terms of installation, while installing as well as after installation. For example, depending on the implementation of the system, additional inductive modules may easily be provided to the lighting system and at least one of the inductive modules may be displaced to another area of interest neighboring the lighting system.

Through the functional unit of the inductive module, different functions may be provided to the lighting system which gains in modularity. There may be one function imparted per inductive module, or one inductive module may comprise a plurality of functional units with different functions. For example, the functional unit may be any one of: a lighting unit, a display unit, an antenna unit, a sensing unit, a speaker unit, an air cleaning unit such as a UV light source, etc. The sensing unit may comprise a pollution sensor, a motion sensor, a humidity sensor, a light sensor, a temperature sensor, a visibility sensor, an image capturing sensor, a radar sensor, a sound sensor, a voice recorder, a C02 sensor, a NOx sensor, a SOx sensor, a smoke sensor, a biological threat sensor, an infrared sensor, a thermal sensor. It is also to be noted that the inductive module with the lighting unit may also comprise additional functional units with different functions in addition to a lighting function.

Further, since the primary wire is received within the envelope extending through the through-hole of the housing, the plurality of inductive modules are supported in a stable manner in an environment with adverse conditions. The envelope may be shaped to accommodate for the intended illumination.

In an embodiment, the envelope is made in a single piece, e.g. as a flexible sheath to the primary wire, and the plurality of inductive modules may be arranged one after the other onto the envelope to be positioned in place. In another embodiment, the envelope is made of a plurality of portions configured for being assembled one to the other and the plurality of inductive modules may be arranged onto a corresponding envelope portion before assembly of the envelope portions together.

The lighting system above may be adapted for outdoor lighting or industrial lighting. By outdoor lighting and industrial lighting, it is meant lighting adapted for roads, tunnels, industrial plants, stadiums, airports, harbors, rail stations, campuses, parks, cycle paths, pedestrian paths, or pedestrian zones for example, and industrial and outdoor lighting systems can be used notably for the lighting of an outdoor area, such as roads and residential areas in the public domain, private parking areas and access roads to private building infrastructures, warehouses, industry halls, etc.

According to a preferred embodiment, the envelope is a rigid envelope.

By rigid, it is meant a self-standing envelope without the need of additional support as a structural aid.

In this manner, support of the plurality of inductive modules may be improved.

According to an exemplary embodiment, the trough-hole is configured for cooperating with the envelope to position the inductive module in a plurality of predetermined positions with respect to the envelope. By this approach, an orientation of the inductive module may be adjusted to be better suited to the needs and/or environment of the lighting system. Depending on embodiments, the adjustment in orientation may be performed before or after arranging the inductive module onto the envelope.

According to a preferred embodiment, the housing comprises an inner peripheral wall and an outer peripheral wall substantially surrounding the inner peripheral wall

Preferably, the magnetic core may be located between the inner peripheral wall and the outer peripheral wall. To favor inductive coupling, the inner peripheral wall of the through-hole may be made of a non-magnetic material, e.g. plastic, aluminum, and a corresponding portion of the envelope may also be made of a non-magnetic material, e.g. plastic, aluminum.

In this way, the protection given by the enclosure of the housing is improved.

According to an exemplary embodiment, the inner peripheral wall of the housing is delimiting the through-hole, said inner peripheral wall being configured to be rotatable around the envelope.

In this manner, rotation motions of the plurality of inductive modules are not impinged by the inner peripheral wall of the housing in contact with the envelope. The inner peripheral wall may preferably comprise a continuous surface and may correspond in dimensions with dimensions of the envelope. The inner peripheral wall may promote motions of the plurality of inductive modules around the envelope, thereby preventing damage due to an undue resistance of the plurality of inductive modules when faced with strong winds for example.

According to an exemplary embodiment, the housing has an inner peripheral wall with an external surface delimiting the through-hole. The external surface defines a profile including a first edge. The envelope has an external surface defining a profile including a second edge configured for cooperating with the first edge. When arranging the housing onto the envelope, the housing is arranged in a predetermined position with respect to the envelope, as seen in a plane perpendicular to an axis of the through-hole.

In this manner, by aligning the first edge and the second edge, rotation of the plurality of inductive modules around the envelope is prevented and the orientation related to the functionality of the plurality of inductive modules may be kept despite adverse environment conditions.

Note that although the presence of a single edge may be sufficient to prevent rotation, the external surface of the through-hole may comprise multiple edges and define a regular or an irregular polygonal shape, e.g. a triangle, a square, a pentagon, a hexagon, etc. In an embodiment, the external surface of the through-hole has a regular octagon profile, and the external surface of the envelope defines a corresponding regular octagon profile. When arranging an inductive module of the plurality of inductive modules onto the envelope, the overall orientation of said inductive module may be adjusted in steps of 45° thanks to the octagon profile with respect to the envelope. The adjustment in steps may be achieved by a discrete rotation of the inductive module with respect to a main axis of the envelope prior to the arrangement of the inductive module onto the envelope.

According to a preferred embodiment, the inner peripheral wall has an external surface which is substantially complementary to an external surface of the envelope.

In this way, the arrangement of the plurality of inductive modules onto the envelope has minimized freedom of movements in a plane perpendicular to the axis of the through-hole, therefore improving the stability and position of the lighting system installation. By complementary, it is meant a substantial match in shape and dimensions between the external surface of the inner peripheral wall and the external surface of the envelope to minimize an empty space volume between both external surfaces.

According to an exemplary embodiment, the inner peripheral wall is substantially cylindrical.

In this manner, the shape of said inner peripheral wall may be kept simple from a design point of view while enabling rotation.

According to a preferred embodiment, the outer peripheral wall is provided with a support configured for supporting at least partially the functional unit, preferably for supporting the at least one light source.

In this way, an orientation of the at least one light source may be well defined in function of the underlying support. Alternatively, a different functional unit may be provided to the support and the support may be configured to be suited for the arrangement of said functional unit or a part of said functional unit.

According to an exemplary embodiment, the support is shaped as a wing, preferably integrated with the outer peripheral wall. In this manner, a profile of the outer peripheral wall may be less prone to air movements. Also, the wing shape may comprise a substantially flat surface onto which an element of the functional unit, e.g. the at least one light source, may be provided.

According to a preferred embodiment, the wing extends in a plane substantially parallel to an axis of the through-hole.

In this way, the overall shape of the outer peripheral wall may be simplified.

According to an exemplary embodiment, the wing extends at least partially below the through- hole.

In this manner, the center of gravity of the inductive module may be located below the envelope which improves the positioning stability of the inductive module.

According to a preferred embodiment, the wing extends from an area in a horizontal plane extending through the through-hole to an area vertically below the through-hole.

In this way, a relevant part of the functional unit, e.g. the at least one light source, may be oriented towards the ground due to a favorable weight balance.

According to an exemplary embodiment, the housing is slidable over the envelope.

In this manner, the inductive module may be easily installed and positioned within the lighting system, which improves the overall modularity of the system especially to adapt to changes in use and environments. Additionally, the slidable surfaces in contact may be provided with a given roughness to improve or prevent a motion along the envelope of the inductive module. In an embodiment, the envelope may be provided with surfaces having different roughness to define slidable portions.

According to another embodiment, the lighting system further comprises a fixation means, preferably a clamping means, configured for fixing a position of at least one of the inductive modules with respect to the envelope.

It may advantageously provide to the lighting system a means of preventing the inductive module from moving transversally along the envelope and/or for rotating around the envelope. The fixation means may be configured for getting fixed relative to the envelope mechanically and/or chemically. The fixation means may be fixed independently from the inductive module and serves as stop to the inductive module or may fix directly the inductive module to the envelope.

According to different embodiments, the fixation means may be an element separate from the inductive module and the envelope, may be comprised in the housing, or may be comprised in the envelope. In an embodiment, the inductive module may be slid along the envelope and/or rotated around the envelope to a desired position before being fixed in said desired position using the fixation means.

According to a preferred embodiment, the envelope comprises one or more tube portions.

In this way, the length and shape of the envelope may be easily modulated according to the needs, e.g. the lighting needs, of the installation site. For example, the one or more tube portions may be categorized into curved portions and straight portions serving as building blocks for the envelope. The one or more tube portions may be assembled together mechanically, e.g. bayonet mount, screwing mount, fitting mount, and/or chemically, e.g. glue. Additionally, the tube portion may comprise sections delimited by shoulders, said sections configured for restraining motions of the inductive module along the tube portion of the envelope when the one or more tube portions are assembled together.

According to an exemplary embodiment, at least one of the plurality of inductive modules further comprises a balancing means, said balancing means being provided to the housing of the inductive module; and, when orienting the envelope substantially horizontally, the balancing means is configured for self-orienting the housing to a preset orientation with respect to the envelope by gravity.

In this manner, the balancing means, coupled with a freedom of motion of the plurality of inductive modules around the envelope, may cause a positioning of the at least one of the plurality of inductive modules to be restored by equilibrium. In an embodiment, the balancing means may be fixed relative to said at least one of the plurality of inductive modules. In another embodiment, the balancing may be adjustable, in weight or in position, relative to said at least one of the plurality of inductive modules. In a particular embodiment, each of the plurality of inductive modules further comprises a balancing means. Additionally the plurality of inductive modules may comprise a common balancing means linking them together so that the orientation of the plurality of inductive modules is controlled in a joint manner. In yet another embodiment, the balancing means may be individually adjusted for each of the plurality of inductive modules and different orientations may be obtained, thereby increasing the modularity of the system.

It is to be noted that placing the balancing means such that the overall center of gravity of the inductive module is substantially close to a rotation axis of the inductive module may allow for an increased stability of the preset orientation in regards of environmental changes; placing the balancing means such that the overall center of gravity of the inductive module is substantially away from the rotation axis of the inductive module may allow for an increased precision in the preset orientation.

According to a preferred embodiment, the functional unit is at least partially provided to an external surface of the housing, preferably the at least one light source is provided to the external surface of the housing.

In this way, illumination by the at least one light source is direct and the loss of emitted light is diminished. Preferably the at least one light source of the lighting unit is an LED light source. It is to be noted that a part of the functional unit different from the lighting unit may also be advantageously provided to the external surface of the housing to improve its functioning.

According to an exemplary embodiment, the at least one light source comprises an OLED light source or a QLED light source, preferably an OLED panel light source.

In this manner, one can obtain light emitted from the at least one light source with a high intensity, suitable for providing a desired visibility level in an outdoor or industrial environment, while having a substantially low power consumption, which is better suited to inductively powered systems. In an embodiment, there may be more than one light source per lighting unit of the corresponding inductive module.

According to a preferred embodiment, the electrical power provided to the primary wire has a frequency above 20kHz.

In this way, the electrical power is provided through a signal above a frequency audible by a human being.

According an exemplary embodiment, the secondary wire of the electromagnetic coupling means has less than 40 windings, preferably less than 30 windings, more preferably less than 20 windings, most preferably less than 10 windings. In this manner, the inductive module may operate at a substantially high frequency, preferably above a frequency audible by a human being. In an embodiment, the AC current circulating in the primary wire may have a frequency above 20kHz and the number of windings of the secondary wire around the magnetic core may be reduced in order to operate at a higher frequency corresponding to the frequency of the power in the primary wire.

According to a preferred embodiment, the power supply is configured to provide an apparent power of the electrical power to the primary wire below 9W.

In this way, a lighting system with low power consumption may be realized. In an embodiment, the at least one light source comprises an OLED or a QLED light source which is adapted for being supplied with an amount of power below 9W.

According to an exemplary embodiment, an inductive module of the plurality of inductive modules further includes a heat dissipation element.

In this manner, heat dissipation by said inductive module may be better managed. In an embodiment, the heat dissipation element may serve as the balancing means due to its substantially large weight relative to a weight of the inductive module.

According to a preferred embodiment, the envelope is suitable for arranging at least three inductive modules onto it, preferably for arranging at least four inductive modules onto it.

In this way, a functional modularity of the lighting system is increased.

According to an exemplary embodiment, the magnetic core has a length longer than half its inner diameter, preferably longer than its inner diameter.

In this manner, the magnetic core may be designed to have an improved ratio of effective length with respect to effective area for inductive coupling purposes.

According to a preferred embodiment, the housing comprises a plurality of protuberances protruding in the through-hole, said plurality of protuberances being configured for centering the magnetic core relative to the primary wire. In this way, efficiency for the inductive coupling may be improved.

According to an exemplary embodiment, the housing is a closed housing enclosing the electromagnetic coupling means.

In this manner, electrical components of the inductive module may be better protected against adverse environmental conditions. Preferably, the housing may satisfy an IP66 rating.

According to a preferred embodiment, a portion of the housing is orientable such that an orientation of at least part of the functional unit, preferably a main direction of illumination of the at least one light source can be altered.

In this way, the modularity of illumination of the lighting unit of the inductive module may be further improved. In an embodiment, the portion of the housing is made of a flexible material which can be deformed. In another embodiment, the portion of the housing may be orientable due to one or more articulations of the housing. Additionally, the at least one light source may be a flexible OLED panel which allows for a curved illumination light source. It is to be noted that a part of the functional unit different from the lighting unit may also be advantageously provided to the orientable portion of the housing to improve its functioning.

The inventors also found it useful to provide a lighting system and an inductive power supply device allowing for a modular and user-friendly installation, and with a stable intensity of the light emitted.

According to a second aspect of the invention, there is provided a lighting system, preferably for outdoor lighting or industrial lighting. The lighting system comprises a power supply, a feedback loop, and at least one lighting module. The power supply is configured for generating electrical power provided to a primary wire forming a current loop. The power supply includes a switching amplifier being supplied in power, and the switching amplifier is configured for outputting the electrical power to the primary wire based on a signal input. The primary wire may preferably be directly connected to the switching amplifier. The feedback loop is connected to the switching amplifier, preferably directly. The feedback loop comprises: a current sensing means coupled to the primary wire and configured for outputting a feedback signal based on the current sensed in the primary wire; a controlling means, preferably a microcontroller, configured for outputting a first waveform signal based on the feedback signal; and the first waveform signal is provided as an input signal to the switching amplifier. The at least one lighting module is configured for receiving power from the power supply. The at least one lighting module includes an electromagnetic coupling means, and at least one light source. The electromagnetic coupling means comprises: a magnetic core configured for receiving the current loop of the primary wire; and a secondary wire wound around a portion of the magnetic core and configured for coupling inductively to the primary wire. The at least one light source, preferably a light emitting diode, is connected to the secondary wire. The electromagnetic coupling means is configured for supplying current to the at least one light source.

Note that an inductive functional system may be implemented similarly as described above with at least one inductive module instead of the at least one lighting module. The at least one inductive module includes an electromagnetic coupling means and a functional unit. The electromagnetic coupling means comprises a magnetic core configured for receiving the current loop of the primary wire, and a secondary wire wound around a portion of the magnetic core and configured for coupling inductively to the primary wire. The functional unit is connected to the secondary wire. The electromagnetic coupling means is configured for providing current to the functional unit.

Through the functional unit of the at least one inductive module, different functions may be provided to the inductive functional system which gains in modularity. There may be one function imparted to the at least one inductive module, or the at least one inductive module may comprise a plurality of functional units with different functions. For example, the functional unit may be any one of: a lighting unit, a display unit, an antenna unit, a sensing unit, a speaker unit, an air cleaning unit such as a UV light source, etc. The sensing unit may comprise a pollution sensor, a motion sensor, a humidity sensor, a light sensor, a temperature sensor, a visibility sensor, an image capturing sensor, a radar sensor, a sound sensor, a voice recorder, a C02 sensor, a NOx sensor, a SOx sensor, a smoke sensor, a biological threat sensor, an infrared sensor, a thermal sensor. It is also to be noted that an inductive module with a lighting unit may also comprise additional functional units with different functions in addition to a lighting function.

In the lighting system according to the invention, the power supply provides AC power to the primary wire. The at least one lighting module receives the AC power from the primary wire via the secondary wire due to the electromagnetic induction phenomenon using the magnetic core of the electromagnetic means.

Since the power is supplied to the at least one lighting module using the electromagnetic induction phenomenon, there is no need for a physical coupling between the power supply and the at least one lighting module using wires for example. Thus, the at least one lighting module may be easily installed and positioned without complex electrical wiring required. It contributes to a high modularity of the system in terms of installation, while installing as well as after installation. For example, depending on the implementation of the system, additional lighting modules may easily be provided to the lighting system and the at least one lighting module may be displaced to light another area neighboring the lighting system.

By using a switching amplifier, the power may be more efficiently supplied to the primary wire with less waste by heat emission. Additionally, the switching amplifier may allow for an improved reactivity of the power supplied as well as an improved modularity with respect to an addition or subtraction of a lighting module, as well as being substantially insensitive to noise. Preferably, a class D audio amplifier is utilized as the switching amplifier in order to improve efficiency and lessened the power dissipated as heat.

By providing a feedback loop connected to the switching amplifier, the power supplied to the primary wire may be regulated. In an embodiment, the feedback loop is configured for obtaining a constant AC current supply, in amplitude and frequency, through the primary wire independently of a load of the primary wire. In doing so, no driver is needed within the lighting system due to the characteristics of the power delivery.

The lighting system may be adapted for outdoor lighting or industrial lighting. By outdoor lighting and industrial lighting, it is meant lighting adapted for roads, tunnels, industrial plants, stadiums, airports, harbors, rail stations, campuses, parks, cycle paths, pedestrian paths, or pedestrian zones for example, and industrial and outdoor lighting systems can be used notably for the lighting of an outdoor area, such as roads and residential areas in the public domain, private parking areas and access roads to private building infrastructures, warehouses, industry halls, etc.

According to a preferred embodiment, the at least one lighting module further includes a current converting means, preferably a rectifier, configured for converting an AC current from the secondary wire to a DC current supplied to the at least one light source.

In this manner, the at least one lighting module may comprise a connected DC load. In an embodiment, the current converting means may be a full-wave bridge rectifier.

According to an exemplary embodiment, the at least one lighting module further includes an inductor element connected in series between the electromagnetic coupling means and the current converting means.

Because current converting means may be highly nonlinear components, the current converting means may introduce high frequency harmonics in the AC current waveform of the primary wire. These high frequency harmonics may increase as there is more lighting modules coupled to the primary wire. By adding an inductor element in series between the electromagnetic coupling means and the current converting means, the high frequency harmonics introduced may be reduced in the primary wire without substantially affecting the power factor.

According to a preferred embodiment, the lighting system further comprises at least two, preferably at least three, more preferably at least four lighting modules.

In this way, the modularity of the lighting system is improved and a single power supply may be needed to provide power for a plurality of light sources.

According to an exemplary embodiment, the at least one lighting module further includes a heat dissipation element, preferably configured for dissipating heat from the current converting means.

In this manner, heat dissipation by the at least one lighting module may be better managed.

According to a preferred embodiment, the power supply further comprises: a step-down converter, preferably a buck converter; a switching means, preferably a relay, coupled to said step-down converter; and wherein the switching amplifier is supplied in power by the step-down converter.

In this way, the power provided from an electrical grid, for example, may be adapted for powering a lighting system with a substantially low power consumption. The switching means may be used for controlling whether there is supply of power to the lighting system.

According to an exemplary embodiment, the at least one light source of the at least one lighting module is an OLED or a QLED.

In this manner, one can obtain light emitted from the at least one lighting module with a high intensity, suitable for providing a desired visibility level in a given environment, for example in an outdoor environment, while having a substantially low power consumption. In an embodiment, there may be more than one light source per lighting module.

According to a preferred embodiment, the feedback loop further comprises at least one filter circuit, preferably an LC filter circuit, said at least one filter circuit configured for converting the first waveform signal into a second waveform signal. In this way, characteristics of the first waveform signal may be modified in order to serve as an input signal to the switching amplifier. The characteristics of the first waveform signal that can be modified may be an amplitude, a frequency, and/or a waveform shape of the first waveform signal. For example, the first waveform signal outputted by the microcontroller may be a square waveform signal, and the at least one filter circuit may convert the first waveform signal into a second waveform signal with the same frequency and amplitude but sinusoidal. In another embodiment, the first waveform signal is directly usable as the input signal to the switching amplifier and there is no need for the at least one filter circuit.

According to an exemplary embodiment, the feedback loop further comprises: an adjustable voltage means, preferably a potentiometer, connected between the controlling means and the switching amplifier, controlled by the controlling means, and configured for outputting a third waveform signal based on an inputted waveform signal, such that an amplitude of the third waveform signal is below a predetermined level, wherein the adjustable voltage means output is configured for providing the input signal to the switching amplifier.

In this manner, the controlling means of the feedback loop may control the adjustable voltage means to increase or decrease an amplitude of the third waveform signal until a desired current in the primary wire is reached. By using such a control, the AC current in the primary wire may be stabilized with constant characteristics independently of the load of the at least one lighting module. In an embodiment, the feedback loop comprises the adjustable voltage means and the at least one filter circuit, said at least one filter circuit being connected in series between the controlling means and the adjustable voltage means.

According to a preferred embodiment, the controlling means is configured for controlling the adjustable voltage means to output a substantially low voltage, upon detection of an absence of current by the feedback loop.

In this way, the amplitude of the third waveform signal serving as the input signal to the switching amplifier may be limited to a safe value, thereby preventing the switching amplifier for outputting power to the primary wire that could electrically damage the at least one lighting module.

According to an exemplary embodiment, the input signal has a frequency above 20kHz. In this manner, the signal is above a frequency audible by a human being.

According to a preferred embodiment, the secondary wire of the electromagnetic coupling means has less than 40 windings, preferably less than 30 windings, more preferably less than 20 windings, most preferably less than 10 windings.

In this way, the at least one lighting module may operate at a substantially high frequency, preferably above a frequency audible by a human being. In an embodiment, the AC current circulating in the primary wire may have a frequency above 20kHz and the number of windings of the secondary wire around the magnetic core may be reduced in order to operate at a higher frequency corresponding to the frequency of the power in the primary wire.

According to a preferred embodiment, the apparent supplied power through the primary wire is below 9W.

In this manner, a lighting system with low power consumption may be realized. In an embodiment, the at least one light source is an OLED or a QLED light source which is adapted for being supplied with an amount of power below 9W.

According to an exemplary embodiment, the lighting system further comprises at least one functional module configured for receiving power from the power supply by inductive coupling.

In this way, additional functions may be provided to the lighting system which gains in modularity. There may be one function added per functional module, or one functional module may comprise a plurality of functions. For example, the functional module may be any one of: a display module, an antenna module, a sensing module, a speaker module, an air cleaning module such as a UV light source, etc. The sensing module may comprise a pollution sensor, a motion sensor, a humidity sensor, a light sensor, a temperature sensor, a visibility sensor, an image capturing sensor, a radar sensor, a sound sensor, a voice recorder, a C02 sensor, a NOx sensor, a SOx sensor, a smoke sensor, a biological threat sensor, an infrared sensor, a thermal sensor.

It is to be noted that the at least one lighting module may also comprise additional functions similar to the ones described with respect to the functional modules in addition to a lighting function.

The skilled person will understand that the hereinabove described technical considerations and advantages for lighting system embodiments also apply to the below described corresponding inductive power supply device embodiments, mutatis mutandis. According to a third aspect of the invention, there is provided an inductive power supply device for use in a lighting system. The inductive power supply device comprises: a power supply configured for generating electrical power provided to a primary wire forming a current loop, including: a switching amplifier being supplied in power, wherein the switching amplifier is configured for outputting the electrical power to the primary wire based on an input signal, a feedback loop connected to the switching amplifier, comprising: a current sensing means coupled to the primary wire and configured for outputting a feedback signal based on the current sensed in the primary wire, a controlling means, preferably a microcontroller, configured for outputting a first waveform signal based on the feedback signal, wherein the first waveform signal is provided as the input signal to the switching amplifier.

According to an exemplary embodiment, the power supply further comprises: a step-down converter, preferably a buck converter; a switching means, preferably a relay, coupled to said step-down converter; and wherein the switching amplifier is supplied in power by the step-down converter.

According to a preferred embodiment, the feedback loop further comprises: at least one filter circuit, preferably an LC filter circuit, said at least one filter circuit configured for converting the first waveform signal into a second waveform signal.

According to an exemplary embodiment, the feedback loop further comprises: an adjustable voltage means, preferably a potentiometer, connected between the controlling means and the switching amplifier, controlled by the controlling means, and configured for outputting a third waveform signal based on an inputted waveform signal, such that an amplitude of the third waveform signal is below a predetermined level, wherein the adjustable voltage means output is configured for providing the input signal to the switching amplifier. According to further aspects of the invention, there are provided a lighting system and an inductive power supply device as above described. These aspects of the invention are defined by the following set of clauses.

1. A lighting system, comprising : a power supply configured for generating electrical power provided to a primary wire forming a current loop, including: a switching amplifier being supplied in power, wherein the switching amplifier is configured for outputting the electrical power to the primary wire based on an input signal, and wherein the switching amplifier and the primary wire are preferably directly connected, a feedback loop connected to the switching amplifier, preferably directly connected, comprising: a current sensing means coupled to the primary wire and configured for outputting a feedback signal based on the current sensed in the primary wire, a controlling means, preferably a microcontroller, configured for outputting a first waveform signal based on the feedback signal, wherein the first waveform signal is provided as the input signal to the switching amplifier, at least one lighting module configured for receiving power from the power supply, including: an electromagnetic coupling means comprising: a magnetic core configured for receiving the current loop of the primary wire, a secondary wire wound around a portion of the magnetic core and configured for coupling inductively to the primary wire, at least one light source, preferably a light emitting diode, connected to the secondary wire, wherein the electromagnetic coupling means is configured for supplying current to the at least one light source.

2. The lighting system of clause 1, wherein the at least one lighting module further includes a current converting means, preferably a rectifier, configured for converting an AC current from the secondary wire to a DC current supplied to the at least one light source.

3. The lighting system of clause 2, wherein the at least one lighting module further includes an inductor element connected in series between the electromagnetic coupling means and the current converting means. The lighting system of any one of the previous clauses, further comprising at least two, preferably at least three, more preferably at least four lighting modules. The lighting system of any one of clauses 2-4, wherein the at least one lighting module further includes a heat dissipation element, preferably configured for dissipating heat from the current converting means. The lighting system of any one of the previous clauses, wherein the power supply further comprises: a step-down converter, preferably a buck converter; a switching means, preferably a relay, coupled to said step-down converter; and wherein the switching amplifier is supplied in power by the step-down converter. The lighting system of any one of the previous clauses, wherein the at least one light source of the at least one lighting module is an OLED or a QLED. The lighting system of any one of the previous clauses, wherein the feedback loop further comprises: at least one filter circuit, preferably an LC filter circuit, said at least one filter circuit configured for converting the first waveform signal into a second waveform signal. The lighting system of any one of the previous clauses, wherein the feedback loop further comprises: an adjustable voltage means, preferably a potentiometer, connected between the controlling means and the switching amplifier, controlled by the controlling means, and configured for outputting a third waveform signal based on an inputted waveform signal, such that an amplitude of the third waveform signal is below a predetermined level, wherein the adjustable voltage means output is configured for providing the input signal to the switching amplifier. The lighting system of the previous clause, wherein the controlling means is configured for controlling the adjustable voltage means to output a substantially low voltage, upon detection of an absence of current by the feedback loop. The lighting system of any one of the previous clauses, wherein the input signal has a frequency above 20kHz. The lighting system of any one of the previous clauses, wherein the secondary wire of the electromagnetic coupling means has less than 40 windings, preferably less than 30 windings, more preferably less than 20 windings, most preferably less than 10 windings. The lighting system of any one of the previous clauses, wherein the apparent supplied power through the primary wire is below 9W. The lighting system of any one of the previous clauses, further comprising at least one functional module configured for receiving power from the power supply by inductive coupling. An inductive power supply device for use in a lighting system, comprising : a power supply configured for generating electrical power provided to a primary wire forming a current loop, including: a switching amplifier being supplied in power, wherein the switching amplifier is configured for outputting the electrical power to the primary wire based on an input signal, and wherein the switching amplifier and the primary wire are preferably directly connected, a feedback loop connected to the switching amplifier, preferably directly connected, comprising: a current sensing means coupled to the primary wire and configured for outputting a feedback signal based on the current sensed in the primary wire, a controlling means, preferably a microcontroller, configured for outputting a first waveform signal based on the feedback signal, wherein the first waveform signal is provided as the input signal to the switching amplifier. The inductive power supply device of the previous clause wherein the power supply further comprises: a step-down converter, preferably a buck converter; a switching means, preferably a relay, coupled to said step-down converter; and wherein the switching amplifier is supplied in power by the step-down converter. The inductive power supply device of clause 15 or 16, wherein the feedback loop further comprises: at least one filter circuit, preferably an LC filter circuit, said at least one filter circuit configured for converting the first waveform signal into a second waveform signal. The inductive power supply device of any one of clauses 15-17, wherein the feedback loop further comprises: an adjustable voltage means, preferably a potentiometer, connected between the controlling means and the switching amplifier, controlled by the controlling means, and configured for outputting a third waveform signal based on an inputted waveform signal, such that an amplitude of the third waveform signal is below a predetermined level, wherein the adjustable voltage means output is configured for providing the input signal to the switching amplifier. BRIEF DESCRIPTION OF THE FIGURES

This and other aspects of the present invention will now be described in more detail, with reference to the appended drawings showing a currently preferred embodiment. Like numbers refer to like features throughout the drawings.

Figure 1 illustrates schematically an exemplary embodiment of a lighting system according to the invention;

Figures 2A-2E illustrate schematically side views of external surface profiles of exemplary embodiments of a lighting system according to the invention;

Figure 3A-3C show an inductive module with a lighting unit of exemplary embodiments of a lighting system according to the invention;

Figures 4A-4C picture an overview, a close-up view, and an exploded view, respectively, of another exemplary embodiment of a lighting system according to the invention;

Figure 5 shows schematically an exemplary embodiment of a lighting system according to the invention;

Figure 6 shows schematically another exemplary embodiment of a lighting system according to the invention;

Figure 7 illustrates an electronic circuit of an exemplary embodiment of a lighting system according to the invention.

DESCRIPTION OF EMBODIMENTS

Figure 1 shows schematically an exemplary embodiment of a lighting system according to the present invention. The lighting system 100 comprises a power supply 110, and a plurality of inductive modules 120.

The lighting system 100 may be adapted for outdoor or industrial lighting. By outdoor lighting and industrial lighting, it is meant lighting adapted for roads, tunnels, industrial plants, stadiums, airports, harbors, rail stations, campuses, parks, cycle paths, pedestrian paths, or pedestrian zones for example, and outdoor and industrial lighting systems can be used notably for the lighting of an outdoor area, such as roads and residential areas in the public domain, private parking areas and access roads to private building infrastructures, warehouses, industry halls, construction sites, etc.

The power supply 110 is configured for generating electrical power provided to a primary wire 111 forming a current loop. In an embodiment, a frequency of a signal carrying the electrical power generated may be above 20kHz. The power generated through the primary wire 111 may be received by the plurality of inductive modules 120. In an embodiment, there may be two, preferably at least three, more preferably at least four inductive modules 120.

Each inductive module 120 of the plurality of inductive modules 120 may be configured in a similar manner or may be different from each other. The inductive module 120 comprises an electromagnetic coupling means including a magnetic core 121 and a secondary wire 122, and a functional unit. At least one inductive module 120 of the plurality of inductive modules comprises a functional unit corresponding to a lighting unit with at least one light source 123, preferably at least one light emitting diode.

Through the functional unit of the inductive module 120, different functions may be provided to the lighting system 100 which gains in modularity. There may be one function imparted per inductive module 120, or one inductive module 120 may comprise a plurality of functional units with different functions. For example, the functional unit may be any one of: a lighting unit, a display unit, an antenna unit, a sensing unit, a speaker unit, an air cleaning unit such as a UV light source, etc. The sensing unit may comprise a pollution sensor, a motion sensor, a humidity sensor, a light sensor, a temperature sensor, a visibility sensor, an image capturing sensor, a radar sensor, a sound sensor, a voice recorder, a C02 sensor, a NOx sensor, a SOx sensor, a smoke sensor, a biological threat sensor, an infrared sensor, a thermal sensor. It is also to be noted that the inductive module 120 with the lighting unit may also comprise additional functional units with different functions in addition to a lighting function.

For convenience reasons, the inductive modules 120 illustrated in Figure 1, Figures 3A-3C, and Figures 4A-4C may comprise a lighting unit with at least one light source 123; the skilled person will understand that embodiments of the application are not limited to inductive modules with the functional unit corresponding uniquely to the lighting unit but are equally applicable to other functional units embodiments.

The magnetic core 121 is configured for receiving the current loop of the primary wire 111. The secondary wire 122 is wound around a portion of the magnetic core 121 in a certain number of windings 122’, and is configured for coupling inductively to the primary wire 111. The secondary wire 122 of the electromagnetic coupling means may have less than 40 windings 122’, preferably less than 30 windings 122’, more preferably less than 20 windings 122’, most preferably less than 10 windings 122’.

The magnetic core 121 may be made of iron. Typically, the magnetic core 121 is cylindrically-shaped with a trough-hole as seen in the direction of the magnetic core main axis, via which the primary wire 111 is passing through. The magnetic core 121 may have a length longer than half its inner diameter, preferably longer than its inner diameter, for an improved coupling efficiency. The electromagnetic coupling means may allow supplying power to the functional unit. In an embodiment, there may be more than one functional unit being supplied in power by the electromagnetic coupling means.

In a preferred embodiment, the inductive module 120 comprises at least one low power light source 123 such as a LED light source, an OLED light source, or a QLED light source. In the embodiment of Figure 1, the at least one light source 123 is a COB LED filament.

Correspondingly, the apparent power provided through the primary wire 111 may be below 9W.

To enhance the coupling efficiency between the primary wire 111 and the electromagnetic coupling means of the inductive module 120, the secondary wire 122 may be wound around the magnetic core 121 such that there is a match in the frequency with current frequency of the primary wire 111. In an embodiment, the frequency to be matched is about 22kHz and the secondary wire 122 is wound 10 times around the magnetic core 121. The inductive module 120 may also be provided with a heat dissipation element (not shown) in order to prevent the inductive module 120 from overheating.

Each of the plurality of inductive modules 120 further comprises a housing 125 configured for at least partially enclosing the electromagnetic coupling means. The housing 125 comprises an inner peripheral wall with an external surface delimiting the through-hole 125’. The through-hole 125’ corresponds to a central hole of the magnetic core 121. To favor inductive coupling, the inner peripheral wall of the through-hole 125’ may be made of a non-magnetic material, e.g. plastic, aluminum. In the embodiment of Figure 1, the housing 125 covers only a surface of the central hole of the magnetic core 121. In another embodiment, the housing 125 may be a closed housing enclosing the magnetic core 121. In yet another embodiment, the housing 125 may be a closed housing enclosing the inductive module 120.

In the embodiment of Figure 1, the inner peripheral wall of the through-hole 125’ has a continuous external surface and defines a profile which is substantially circular. More detailed embodiments of external surface profiles will be seen with respect to Figures 2A-2E. More detailed embodiments of the housing 125 of the inductive module will be seen with respect to Figures 3A- 3C.

The power supply 110 further comprises an envelope 112 configured for receiving the primary wire 111 therein. To favor inductive coupling, a portion of the envelope 112 may be made of a non-magnetic material, e.g. plastic, aluminum. According to embodiments, the envelope 112 may be a flexible envelope, e.g. a sheath of the primary wire, or a rigid envelope, e.g. a tubing of the primary wire, or may comprise flexible portions and rigid portions. By rigid, it is meant a self standing envelope, or self-standing portion, without the need of additional support as a structural aid. For convenience reasons, in the descriptions of Figure 1, Figures 2A-2E, Figures 3A-3C, and Figures 4A-4C, embodiments describe a rigid envelope 112; the skilled person will understand that these embodiments can also be implemented with other kinds of envelopes. The rigid envelope 112 of Figure 1 is configured for extending through the through -hole 125’ of the housing. After arranging the plurality of inductive modules 120 onto the rigid envelope 112 of the power supply, the rigid envelope 112 supports the plurality of inductive modules 120. The rigid envelope 112 may be shaped in one piece or may be assembled in a plurality of portions, assembled in four tube portions in the embodiment of Figure 1. In an embodiment, the rigid envelope 112 may comprise one or more tube portions categorized into curved portions and straight portions serving as building blocks for the rigid envelope 112. The one or more tube portions may be assembled together mechanically, e.g. bayonet mount, screwing mount, fitting mount, and/or chemically, e.g. glue. Additionally, the tube portion may comprise sections delimited by shoulders, said sections configured for restraining motions of the inductive module 120 along the tube portion of the rigid envelope 112 when the one or more tube portions are assembled together.

In an embodiment, the housing 125 may be slidable over the rigid envelope 112. Surfaces of the inner peripheral wall of the through-hole 125’ and of the rigid envelope 112 in contact with each other may be provided with a given texture, or roughness, to improve or prevent a motion of the inductive module 120 along the rigid envelope 112. In an embodiment, the rigid envelope 112 may be provided with surfaces having different roughness to define smooth slidable sections and rough sections. Alternatively or additionally, the trough-hole 125’ may be configured for cooperating with the envelope 112 to position the inductive module 120 in a plurality of predetermined positions with respect to the envelope 112.

Additionally or alternatively, the lighting system 100 may further comprise a fixation means, preferably a clamping means, configured for fixing a position of at least one of the inductive modules 120 with respect to the envelope 112. It may advantageously provide to the lighting system 100 a means of preventing the inductive module 120 from moving along the envelope 112 and/or rotating around the envelope 112. The fixation means may be configured for getting fixed relative to the envelope 112 mechanically and/or chemically. The fixation means may be fixed independently from the inductive module 120 and serves as a stop to the inductive module 120 or may fix directly the inductive module 120 to the envelope 112. According to different embodiments, the fixation means may be an element separate from the inductive module 120 and the envelope 112, may be comprised in the housing 125, or may be comprised in the envelope 112.

An external surface of the rigid envelope 112 may define a profile similar or different to the profile of the inner peripheral wall of the through-hole 125’. In the embodiment of Figure 1, the external surface of the rigid envelope 112 is a continuous surface and defines a substantially circular profile. The external surface of the rigid envelope 112 and the external surface of the through-hole 125’ may be complementary. Due to the continuous profiles of the through -hole 125’ and the rigid envelope 112, the inductive module 120 may rotate about the central hole of the magnetic core 121 around the rigid envelope 112. By gravity, the inductive module 120 may settle itself in position. Additionally, each of the plurality of inductive modules 120 may further comprise a balancing means (not shown).

The balancing means may be provided to the housing 125 of the inductive module, and, when orienting the power supply rigid envelope 112 substantially horizontally, the balancing means may be configured for self-orienting the inductive module 125 to a preset orientation with respect to the power supply rigid envelope 112 by gravity. In an embodiment, the balancing means may be fixed relative to each of the plurality of inductive modules 120. In another embodiment, the balancing means may be adjustable, in weight or in position, relative to each of the plurality of inductive modules 120. Also, the plurality of inductive modules 120 may comprise a common balancing means linking them together so that the orientation of the plurality of inductive modules 120 is controlled in a joint manner.

Figures 2A-2E illustrate schematically side views of external surface profiles of through-holes and corresponding rigid envelopes according to the present invention. The lighting system comprises a power supply (not shown), and a plurality of inductive modules (not shown). Each of the plurality of inductive modules comprises a housing 125 configured for at least partially enclosing an electromagnetic coupling means including a magnetic core (not shown). The housing 125 comprises an inner peripheral wall with an external surface delimiting the through-hole 125’. The through-hole 125’ corresponds to a central hole of the magnetic core. The power supply comprises a rigid envelope 112 configured for receiving a primary wire 111 therein. The rigid envelope 112 is configured for extending through the through-hole 125’ of the housing. In an embodiment, the trough-hole 125’ may be configured for cooperating with the envelope 112 to position the inductive module 120 in a plurality of predetermined positions with respect to the envelope 112.

In the embodiment of Figure 2 A, the housing 125 has an inner peripheral wall with an external surface delimiting the through -hole 125’. The external surface defines a profile including a first edge 125”. The rigid envelope 112 has an external surface defining a profile including a second edge 112’ configured for cooperating with the first edge 125”. When arranging the housing 125 onto the rigid envelope 112, the housing 125 is arranged in a predetermined position with respect to the rigid envelope 112, as seen in a plane perpendicular to an axis of the through-hole 125’.

The housing 125 of the inductive module may be arranged at a predetermined position with respect to the rigid envelope 112 such that both first edge 125” and second edge 112’ coincides. By aligning the first edge 125” and the second edge 112’, rotation of the plurality of inductive modules around the rigid envelope 112 may be prevented and the orientation of the illumination of the plurality of inductive modules may be kept despite adverse environment conditions.

In the embodiment of Figure 2B, the external surface profile of the through -hole 125’ describes a triangle, and the external surface profile of the rigid envelope 112 describes a corresponding triangle. This triangular profile allows the housing 125 of the inductive module to be oriented along three different orientations during installations in steps of 120°, thereby allowing modularity in the illumination of the outdoor lighting system. The adjustment of the orientation in steps may be achieved by a discrete rotation of the inductive module with respect to a main axis of the rigid envelope 112 prior to the arrangement of the inductive module onto the rigid envelope 112.

In the embodiment of Figure 2C, the external surface profile of the through-hole 125’ describes an octagon, and the external surface profile of the rigid envelope 112 describes a corresponding octagon. This octagonal profile allows the housing 125 of the inductive module to be oriented along eight different orientations during installations in steps of 45°. The adjustment of the orientation in steps may be achieved by a discrete rotation of the inductive module with respect to a main axis of the rigid envelope 112 prior to the arrangement of the inductive module onto the rigid envelope 112.

In the embodiment of Figure 2D, the external surface profile of the through-hole 125’ has a continuous tear-shaped surface defined by a first maximum lateral dimension dl. The external surface profile of the power rigid envelope 112 has a continuous surface describing a circle, and has a second maximum lateral dimension d2 smaller than the first maximum lateral dimension dl. The shape of the through-hole 125’ may favor orientation of the housing 125 along a certain direction. In an alternative embodiment, the external surface profile of the through -hole 125’ has a continuous surface describing a circle, and the external surface profile of the power supply rigid envelope 112 has a continuous tear-shaped surface.

In the embodiment of Figure 2E, both the external surface profile of the through -hole 125’ and the external surface profile of the rigid envelope 112 describe a circle. The housing 125 comprises a plurality of protuberances 125”’ protruding in the through-hole 125’. The plurality of protuberances 125”’ is configured for centering the magnetic core relative to the primary wire 111. In the embodiment of Figure 2E, the plurality of protuberances 125”’ is dome-shaped and located at four points at regular intervals along the external surface profile of the through -hole 125’. The skilled person will understand that the plurality of protuberances 125”’ may adopt different shapes and numbers to fulfill its functions.

In the embodiments of Figures 2D and 2E, the inner peripheral wall is configured to be rotatable around the rigid envelope 112. In the embodiments of Figures 2A, 2B, 2C, and 2E, the external surface of the inner peripheral wall may be substantially complementary to the external surface of the rigid envelope 112. By complementary, it is meant a substantial match in shape and dimensions between the external surface of the inner peripheral wall and the external surface of the envelope 112 to minimize an empty space volume between both external surfaces.

Figures 3A-3C shows inductive modules with a lighting unit of exemplary embodiments of an outdoor lighting system according to the present invention. The inductive module 120 comprises an electromagnetic coupling means including a magnetic core (not shown) and a secondary wire (not shown), and a functional unit. In the embodiments of Figures 3A-3C, the functional unit corresponds to a lighting unit including at least one light source 123.

The inductive module 120 further comprises a housing 125 configured for at least partially enclosing the electromagnetic coupling means. The housing 125 comprises an inner peripheral wall 125b with an external surface delimiting the through -hole 125’. The through-hole 125’ corresponds to a central hole of the magnetic core. The inner peripheral wall 125b may be configured to be rotatable around a rigid envelope (not shown). More particularly, in the embodiment of Figures 3A-3C, the inner peripheral wall 125b is substantially cylindrical and extends along the axis A of the through -hole 125’.

The housing 125 may be slidable over the rigid envelope. Surfaces of the inner peripheral wall 125b of the through-hole 125’ and of the rigid envelope in contact with each other may be provided with a given texture, or roughness, to improve or prevent a motion of the inductive module 120 along the rigid envelope. In an embodiment, the rigid envelope may be provided with surfaces having different roughness to define smooth slidable sections and rough sections.

In the embodiment of Figures 3A-3C, the housing 125 is a closed housing enclosing the inductive module 120, preferably such that the housing 125 may satisfy an IP66 rating. The housing 125 may further have an outer peripheral wall 125a substantially surrounding the inner peripheral wall 125b. Preferably, the magnetic core may be located between the inner peripheral wall 125b and the outer peripheral wall 125a.

The at least one light source 123 may comprise an OLED panel, said OLED panel being flexible. The outer peripheral wall 125a may be provided with a support for the at least one light source 123. In the embodiment of Figures 3A-3C, the support is integrated with the outer peripheral wall 125a and shaped as a wing with a base portion 125c and a wing portion 125d. The wing extends in a plane substantially parallel to the axis A of the through-hole 125’. The wing extends at least partially below the through -hole 125’. More particularly, the base portion 125c of the wind extends from an area in a horizontal plane extending through the through -hole 125’; and the wing portion 125d of the wing extends to an area vertically below the through-hole 125’. The base portion 125c of the wing comprises the through-hole 125’. The wing portion 125d of the wing is provided, on its convex surface serving as the support, with the at least one light source 123. In an embodiment, a portion of the housing 125, the wing portion 125d of the housing for example, is orientable such that a main direction of illumination of the at least one light source 123 can be altered. The portion of the housing 125 may be made of a flexible material which can be deformed. Alternatively or additionally, the portion of the housing 125 may be orientable due to one or more articulations of the housing 125.

Further, a balancing means (not shown) may be provided to the housing 125 of the inductive module. In the embodiment of Figures 3A-3C, the balancing means may be provided within the base portion 125c of the wing, substantially close to a rotation axis A of the inductive module 120. In an embodiment, a heat dissipation element (not shown) may serve as the balancing means.

In the embodiment of Figure 3A, the wing portion 125d is shaped as a virgule allowing an illumination in on main direction at an angle with respect to an horizontal level. In the embodiment of Figure 3B, the wing portion 125d has a substantially round profile allowing an even illumination over an angular arc of at least 180°. In the embodiment of Figure 3C, the wing portion 125d has a flattened egg profile allowing illumination over an angular arc of at least 180° but with a preferential illumination directly below the inductive module.

Figures 4A-4C pictures an overview, a close-up view, and an exploded view, respectively, of another exemplary embodiment of a lighting system according to the present invention. The lighting system 100 comprises a power supply (not shown), and a plurality of inductive modules 120.

The lighting system 100 may be adapted for outdoor or industrial lighting. By outdoor lighting and industrial lighting, it is meant lighting adapted for roads, tunnels, industrial plants, stadiums, airports, harbors, rail stations, campuses, parks, cycle paths, pedestrian paths, or pedestrian zones for example, and outdoor and industrial lighting systems can be used notably for the lighting of an outdoor area, such as roads and residential areas in the public domain, private parking areas and access roads to private building infrastructures, warehouses, industry halls, construction sites, etc.

The power supply is configured for generating electrical power provided to a primary wire 111 forming a current loop. In an embodiment, a frequency of a signal carrying the electrical power generated may be above 20kHz. The power generated through the primary wire 111 may be received by the plurality of inductive modules 120. In the embodiment of Fig.4A, there are two inductive modules 120 comprising a functional unit corresponding to a lighting unit with at least one light source 123.

Each inductive module 120 of the plurality of inductive modules may be configured in a similar manner or may be different from each other. The inductive module 120 comprises an electromagnetic coupling means including a magnetic core 121 and a secondary wire 122, and the functional unit. The magnetic core 121 is configured for receiving the current loop of the primary wire 111. The secondary wire 122 is wound around a portion of the magnetic core 121 in a certain number of windings, and is configured for coupling inductively to the primary wire 111. The secondary wire 122 of the electromagnetic coupling means may have less than forty windings, preferably less than thirty windings, more preferably less than twenty windings, most preferably less than ten windings.

The magnetic core 121 may be made of iron. Typically, the magnetic core 121 is cylindrically-shaped with a trough-hole as seen in the direction of the magnetic core main axis, via which the primary wire 111 is passing through. The magnetic core 121 may have a length longer than half its inner diameter, preferably longer than its inner diameter, for an improved coupling efficiency. The electromagnetic coupling means may allow to supply power to the functional unit, e.g. to the at least one light source 123 of the lighting unit. In an embodiment, there may be more than one functional unit, for example a plurality of light sources 123, being supplied in power by the electromagnetic coupling means for a given inductive module 120.

In a preferred embodiment, the functional unit of inductive module 120 corresponds to a lighting unit comprising at least one low power light source 123 such as a LED light source, an OLED light source, or a QLED light source. In the embodiment of Figs.4A-4C, the at least one light source 123 is an OLED panel. Correspondingly, the apparent power provided through the primary wire 111 may be below 9W.

To enhance the coupling efficiency between the primary wire 111 and the electromagnetic coupling means of the inductive module 120, the secondary wire 122 may be wound around the magnetic core 121 such that there is a match in the frequency with current frequency of the primary wire 111. In an embodiment, the frequency to be matched is about 22kHz and the secondary wire 122 is wound ten times around the magnetic core 121. The inductive module 120 may also be provided with a heat dissipation element 124 in order to prevent the inductive module 120 from overheating. In the embodiment of Fig.4A, the heat dissipation element 124 is configured for dissipating heat from a rectifier circuit (not shown) connected to the secondary wire 122. The heat dissipation element 124 is located on a portion of the housing 125 opposite to the at least one light source 123.

Each of the plurality of inductive modules 120 further comprises a housing 125 configured for at least partially enclosing the electromagnetic coupling means. The housing 125 comprises an inner peripheral wall with an external surface delimiting the through-hole 125’. The through-hole 125’ corresponds to a central hole of the magnetic core 121. In an embodiment, the housing 125 may cover only a surface of the central hole of the magnetic core 121. In another embodiment, the housing 125 may be a closed housing enclosing the magnetic core 121. In the embodiment of Figs.4A-4B, the housing 125 is a closed housing enclosing the inductive module 120. In the embodiment of Fig.4A, the inner peripheral wall of the through-hole 125’ has a continuous external surface and defines a profile which is substantially circular.

The power supply 110 further comprises an envelope 412 configured for receiving the primary wire 111 therein. In the embodiment of Fig.4A, the envelope 412 is a flexible envelope, e.g. a sheath of the primary wire. According to other embodiments, the envelope may be a rigid envelope, e.g. a tubing of the primary wire, or may comprise flexible portions and rigid portions.

In an embodiment, the housing 125 may be slidable over the flexible envelope 412. Surfaces of the inner peripheral wall of the through-hole 125’ and of the flexible envelope 412 in contact with each other may be provided with a given texture, or roughness, to improve or prevent a motion of the inductive module 120 along the flexible envelope 412. In an embodiment, the flexible envelope 412 may be provided with surfaces having different roughness to define smooth slidable sections and rough sections.

Additionally or alternatively, the lighting system 100 may further comprise a fixation means, preferably a clamping means, configured for fixing a position of at least one of the inductive modules 120 with respect to the flexible envelope 412. It may advantageously provide to the lighting system 100 a means of preventing the inductive module 120 from moving along the flexible envelope 412 and/or rotating around the flexible envelope 412. The fixation means may be configured for getting fixed relative to the flexible envelope 412 mechanically and/or chemically. The fixation means may be fixed independently from the inductive module 120 and serves as a stop to the inductive module 120 or may fix directly the inductive module 120 to the flexible envelope 412. According to different embodiments, the fixation means may be an element separate from the inductive module 120 and the envelope 412, may be comprised in the housing 125, or may be comprised in the envelope 412.

Due to the continuous profile of the through -hole 125’ and the relatively small diameter of the flexible envelope 112, the inductive module 120 may rotate about the central hole of the magnetic core 121 around the flexible envelope 112. By gravity, the inductive module 120 may settle itself in position. Additionally, each of the plurality of inductive modules 120 may further comprise a balancing means. The balancing means may be provided to the housing 125 of the inductive module, and, when orienting the power supply flexible envelope 412 substantially horizontally, the balancing means may be configured for self-orienting the inductive module 120 to a preset orientation with respect to the power supply flexible envelope 112 by gravity. In the embodiment of Fig.4A, the heat dissipation element 124 may serve as the balancing means. The balancing means may be located, when the inductive module 120 is settled in position, in the upper half of the inductive module 120, preferably below the through -hole 125’. The inductive module 120 comprises the housing 125 configured for at least partially enclosing the electromagnetic coupling means. The housing 125 comprises an inner peripheral wall 125b with an external surface delimiting the through -hole 125’. The through-hole 125’ corresponds to a central hole of the magnetic core 121.

In the embodiment of Figs.4A-4B, the housing 125 further has an outer peripheral wall 125a substantially surrounding the inner peripheral wall 125b, preferably such that the housing 125 may satisfy an IP66 rating. Preferably, the magnetic core 121 may be located between the inner peripheral wall 125b and the outer peripheral wall 125a. To favor inductive coupling, both the inner peripheral wall 125b and a corresponding portion of the envelope 412 are made of a non magnetic material, e.g. plastic, aluminum.

In the embodiment of Figs.4A-4C, the at least one light source 123 comprises an OLED panel, said OLED panel being flexible. The outer peripheral wall 125a may be provided with a support for the at least one light source 123. In the embodiment of Figs.4A-4C, the support is integrated with the outer peripheral wall 125a and shaped as a wing with a base portion 125c and a wing portion 125d. The wing extends in a plane substantially parallel to the axis of the through- hole 125’. The wing extends at least partially below the through -hole 125’. More particularly, the wing portion 125d of the wing extends to an area vertically below the through-hole 125’.

The base portion 125c of the wing comprises the through-hole 125’. The wing portion 125d of the housing is provided, on its convex surface serving as the support, with the at least one light source 123. The at least one light source 123 may be provided to an external surface of the outer peripheral wall 125a. In the embodiment of Fig.4A-4C, the at least one light source 123 may be fixed to the outer peripheral wall 125a via a frame 123’ with a central transparent window, said frame 123’ being configured for cooperating with railings 123” of the outer peripheral wall 125a. The railings 123” may be provided on one or more sides of the frame 123’, on all sides of the frame 123’ in the embodiment of Figures 4A-4C.In other embodiments, the at least one light source 125a may be fixed via other fixation means, e.g. screws, glue, rivets, etc.

As pictured in Figure 4C, the housing 125 may be completed by a closing element 126.

The closing element 126 may be configured for completing the enclosure of the housing 125. In the embodiment of Figure 4C, the closing element 126 may be configured for completing a lateral side of the housing 125. The closing element 126 may comprise a through-hole portion 126b configured for cooperating with the inner peripheral wall 125b of the housing, and a plugging portion 126a configured for cooperating with the outer peripheral wall 125a of the housing. The closing element 126 and the housing 125 may be retained together via a housing fixation means 126’, preferably a snap-fit fixation.

In an embodiment, a portion of the housing 125, the wing portion 125d for example, may be orientable such that a main direction of illumination of the at least one light source 123 can be altered. The portion of the housing 125 may be made of a flexible material which can be deformed. Alternatively or additionally, the portion of the housing 125 may be orientable due to one or more articulations of the housing 125.

Figure 5 shows schematically an exemplary embodiment of a lighting system according to the present invention. The lighting system 200 comprises a power supply 210, a feedback loop comprising a current sensing means 220 and a controlling means 230, and at least one lighting module 250.

The lighting system 200 may be adapted for outdoor lighting or industrial lighting. By industrial and outdoor lighting, it is meant lighting adapted for roads, tunnels, industrial plants, stadiums, airports, harbors, rail stations, campuses, parks, cycle paths, pedestrian paths, or pedestrian zones for example, and outdoor and industrial lighting systems can be used notably for the lighting of an outdoor area, such as roads and residential areas in the public domain, private parking areas and access roads to private building infrastructures, warehouses, industry halls, constructions sites, etc.

The power supply 210 is configured for generating electrical power provided to a primary wire 140 forming a current loop. The power supply comprises a switching amplifier 211. Preferably, the switching amplifier 211 may be a class D audio amplifier. The switching amplifier 211 is configured for outputting the electrical power to the primary wire 240 based on an input signal. The input signal is originating from the feedback loop. The feedback loop may generate a feedback signal 221 using the current sensing means 220. The current sensing means 220 may be configured for sensing the current going through the primary wire 240. The current sensing means 220 may comprise any one, or a combination, of the following: an operational amplifier, a resistor, an active rectifier circuit, an inductance, a capacitance.

After being generated by the current sensing means 220, the feedback signal may be sent to the controlling means 230. In an embodiment, the controlling means 230 may be a microcontroller. The controlling means 230 is configured for outputting a first waveform signal 231 based on the feedback signal. The first waveform signal 231 may be characterized by a first amplitude, a first frequency, and/or a first waveform shape, e.g. sinusoidal, triangular, square. In the embodiment of Figure 5, the first waveform signal 231 is the input signal of the switching amplifier 211. The first waveform signal 231 may be a sinusoidal signal.

Based on the input signal, the switching amplifier 211 may output power going through the primary wire 240. The switching amplifier 211 may output through the primary wire 240 an alternating current signal amplified relative to the primary wire 240. In the embodiment of Figure 5, the first waveform signal 231 may be a sinusoidal current signal, and the switching amplifier 211 may output an amplified sinusoidal current signal with the same frequency as the first frequency of the first waveform signal 231. In an embodiment, the first frequency, that is the frequency of the input signal, may be above 20kHz.

The power generated through the primary wire 240 may be received by the at least one lighting module 250. In an embodiment, there may be at least two, preferably at least three, more preferably at least four lighting modules 250. The at least one lighting module 250 comprises an electromagnetic coupling means including a magnetic core 251 and a secondary wire 252, and at least one light source 253. The magnetic core 251 is configured for receiving the current loop of the primary wire 240. The secondary wire 252 is wound around a portion of the magnetic core 251 and is configured for coupling inductively to the primary wire 240.

The magnetic core 251 may be made of iron. Typically, the magnetic core 251 is cylindrically-shaped with a trough-hole as seen in the direction of the magnetic core main axis, via which the primary wire 240 is passing through. The electromagnetic coupling means may allow to supply power to the at least one light source 253. In an embodiment, there may be more than one light source 253 being supplied in power by the electromagnetic coupling means.

In a preferred embodiment, the at least one lighting module 250 comprises a low power light source 253 such as a LED light source, an OLED light source, or a QLED light source. Correspondingly, the apparent power provided through the primary wire 240 may be below 9W.

In an embodiment, the lighting system 200 may further comprise at least one functional module (not shown) configured for receiving power from the power supply by inductive coupling. There may be one function added per functional module, or one functional module may comprise a plurality of functions. For example, the functional module may be any one of: a display module, an antenna module, a sensing module, a speaker module, an air cleaning module such as a UV light source, etc. The sensing module may comprise a pollution sensor, a motion sensor, a humidity sensor, a light sensor, a temperature sensor, a visibility sensor, an image capturing sensor, a radar sensor, a sound sensor, a voice recorder, a C02 sensor, a NOx sensor, a SOx sensor, a smoke sensor, a biological threat sensor, an infrared sensor, a thermal sensor. It is to be noted that the at least one lighting module 250 may also comprise additional functions similar to the ones described with respect to the functional modules in addition to a lighting function.

To enhance the coupling efficiency between the primary wire 240 and the electromagnetic coupling means of the at least one lighting module 250, the secondary wire 252 may be wound around the magnetic core 251 such that there is a match in the frequency with current frequency of the primary wire 240. In an embodiment, the frequency to be matched is about 22kHz and the secondary wire 252 is wound 10 times around the magnetic core 251.

The at least one lighting module 250 may also be provided with a heat dissipation element (not shown) in order to prevent the at least one lighting module 250 from overheating. Figure 6 shows schematically another exemplary embodiment of a lighting system according to the present invention. The lighting system 200 comprises a power supply 210, a feedback loop comprising a current sensing means 220 and a controlling means 230, and at least one lighting module 250. Common elements between the embodiments of Figure 5 and Figure 6 have similar functions and features and will not be described again for convenience-sake.

In the embodiment of Figure 6, the power supply 210 may also comprise a switching means 212 and a step-down converter in addition to a switching amplifier 211. The step-down converter 213 may be a buck converter. The step-down converter 213 may be configured for outputting power with a reduced voltage amplitude compared to a voltage amplitude of an inputted power. By doing so, the outputted voltage amplitude of the step-down converter 213 may be better adapted to supply the other electronic components of the lighting system 200. In an embodiment, there may be more than one step-down converter 213 adapted to supply power at different voltage amplitudes to various electronic components of the lighting system 200. The switching means 212, preferably a relay, may be adapted to allow the provision of power to the switching amplifier 211. In another embodiment, additional switching means 212 may be included in the lighting system 200 between the power supply and the corresponding electronic component being supplied.

The lighting system 200 of Figure 6 may comprise two lighting modules 250. The skilled person will understand that such a number of lighting modules 250 is not limitative and that more or less lighting modules 250 may be arranged on a primary wire 240 of the lighting system 200.

Each of the lighting modules 250 may comprise an electromagnetic coupling means including a magnetic core 251 and a secondary wire 252 wound around the magnetic core 251 , and at least one light source 253. The lighting modules 250 may also comprise a current converting means 254. The current converting means 254, preferably a rectifier, a full-wave bridge rectifier in the embodiment of Figure 6, may be configured for converting an AC current from the secondary wire 252 to a DC current supplied to the at least one light source 253. The current converting means 254 coupled in parallel with the at least one light source 254 may be helped by a capacitance 256 coupled in parallel in order to smooth out the power provided by the current converting means 254. The at least one light source 253 may be an LED light source, an OLED light source, or a QLED light source. Additionally, a heat dissipation element (not shown) may be provided to the current converting means 254.

The at least one lighting module 250 may further include an inductor element 255 connected in series between the magnetic core 251 of electromagnetic coupling means and the current converting means 254. Because current converting means 254 may be highly nonlinear components, the current converting means 254 may introduce high frequency harmonics in the AC current waveform of the primary wire 240. These high frequency harmonics may increase as there are more lighting modules 250 coupled to the primary wire 240. By adding the inductor element 255 in series between the electromagnetic coupling means and the current converting means 254, the high frequency harmonics introduced may be reduced in the primary wire 240 without substantially affecting the power factor.

In the embodiment of Figure 6, the feedback loop, in addition to the current sensing means 220 and the controlling means 230, may also comprise an adjustable voltage means 260. The adjustable voltage means 260, preferably a potentiometer, may be connected between the controlling means 230 and the switching amplifier 211. The adjustable voltage means 260 may be controlled by the controlling means 230 via a control signal 232. The adjustable voltage means 260 may be configured for outputting a third waveform signal 261 based on an inputted waveform signal 271, such that an amplitude of the third waveform signal 261 is below a predetermined level. In the embodiment of Figure 6, the adjustable voltage means 260 is configured for providing an input signal to the switching amplifier 211, in other words the input to the switching amplifier 211 corresponds to the third waveform signal 261.

Additionally or alternatively to the adjustable voltage means 260, the feedback loop may also comprise at least one filter circuit 270. The at least one filter circuit 270, preferably at least one LC filter circuit, may be configured for converting the first waveform signal 231 into a second waveform signal 271. In the embodiment of Figure 6, the at least one filter circuit 271 is coupled in series between the controlling means 230 and the adjustable voltage means 260, and the second waveform signal 271 is being inputted to the adjustable voltage means 260.

The feedback loop of the lighting system 200 aims at aiding the switching amplifier 211 in supplying the power through the primary wire 240 in a stabilized manner by providing the input signal, the third waveform signal 261 in Figure 6, to the switching amplifier 211 based on a feedback signal 221. The feedback signal 221 is outputted by the current sensing means 221. Based on the characteristics of the feedback signal 221, the controlling means 230 outputs the first waveform signal 231. The first waveform signal 231 may be characterized by a first amplitude, a first frequency, and/or a first waveform shape. Similarly, the second waveform signal 271 may be characterized by a second amplitude, a second frequency, and/or a second waveform shape; and the third waveform signal 261 may be characterized by a third amplitude, a third frequency, and/or a third waveform shape.

The power outputted by the switching amplifier 211 may take the shape of an amplified sinusoidal signal. The amplitude of the outputted amplified sinusoidal signal may be adapted to the electrical characteristics of the at least one lighting module 250. Similarly, the frequency of the outputted amplified sinusoidal signal may be adapted to the electrical characteristics of the at least one lighting module 250. The amplification may take the form of an amplification in amplitude of the input signal to the switching amplifier. So, the third waveform signal 261 may have a matching waveform shape and a matching frequency with the outputted amplified sinusoidal signal by the switching amplifier. The third amplitude of the third waveform signal 261 may be controlled by the controlling means 230 via the control signal 232 to take into account the amplification capabilities of the switching amplifier.

The first waveform shape of the first waveform signal 231 may be a shape different than a sinusoidal waveform, for example a triangular waveform or a square waveform. So, the at least one filter circuit 270 may be configured for removing high frequency components of the first waveform signal 231 in order to obtain the second waveform signal 271 as a sinusoidal waveform; the second amplitude of which being adjusted by the adjustable voltage means 260 in order to obtain the third waveform signal 261.

Figure 7 illustrates an electronic circuit of an exemplary embodiment of a lighting system according to the present invention. The lighting system 200 comprises a power supply (not shown), a feedback loop comprising a current sensing means 220 and a controlling means 230, and at least one lighting module 250.

In the embodiment of Figure 7, the power supply may include a switching amplifier 211, a first step-down converter 213’ and a second step-down converter 213”. The first step down- converter 213’ may be configured for converting a first voltage amplitude from -45V/+45V to a second voltage amplitude corresponding to -15V/+15V. The second step-down converter 213” may be configured for converting the second voltage amplitude at -15V/+15V to a third voltage amplitude corresponding to 0V/+5V. The first voltage amplitude may be used for supplying power to an operational amplifier of the switching amplifier 211. The second voltage amplitude may be used for supplying power to an operational amplifier of the current sensing means 220. The third voltage amplitude may be used for supplying power to a microcontroller of the controlling means 230, and to a potentiometer of an adjustable voltage means 260.

The switching amplifier 211 of Figure 7 is a class D audio amplifier. The switching amplifier 211 is configured for supplying power to a primary wire 240. The at least one lighting module 250 is inductively coupled to the primary wire 240. The coupling is achieved by an electromagnetic means including a magnetic core 251 and a secondary wire 252. The at least one lighting module 250 may comprise a rectifier 254 configured for converting an AC current into a DC current, helped by a capacitance 256 connected in parallel to smooth out the current outputted by the rectifier, thereby supplying LED light source 253.

The primary wire 240 may form a current loop. A resistance part of the current sensing means 220 and connected in series with the primary wire 240 may provide an input signal to an active rectifier circuit 223 of the current sensing means. The active rectifier circuit 223 may output a feedback signal 221 to the controlling means 230. In the embodiment of Figure 7, the controlling means 230 may output a 23kHz square waveform signal as a first waveform signal 231 , as well as a control signal 232 to control the adjustable voltage means 260. The first waveform signal 231 may be converted into a 23kHz sinusoidal waveform signal as a second waveform signal 271 by a plurality of LC filter circuits 270. The second waveform signal 271 may be fed to the adjustable voltage means 260 before being outputted as an input signal to the switching amplifier 211.

Whilst the principles of the invention have been set out above in connection with specific embodiments, it is to be understood that this description is merely made by way of example and not as a limitation of the scope of protection which is determined by the appended claims.