The invention relates to a charging system for charging an eiectric vehicle. The invention also relates to a plug and to a socket in such charging system. The invention further relates to different other components within such charging system.

Nowadays, the electric vehicle market has made an enormous leap. More and more electric cars (but also other vehicles as electric bikes, motorbikes, Segway's, etc.) are being sold worldwide, which also puts challenges on the use this product, in particular when it comes down to charging the batteries. Most people will charge their electric car most of the times at home. In most homes there are electric sockets available, which are either 16 A or 10 A, For the shortest charging time it !s important to charge at the highest possible charging current. At the same time it is important not to charge at a higher current than what is good for the respective electric socket, i.e. in order not to damage or destroy the electric system or the power grid to which if is connected.

In the prior art various solutions to this problem have been presented. US2014/0120764A1 discloses a socket outlet presenting given intrinsic characteristics so as to be suitable for delivering continuously, and without being damaged, an electrical signal that presents a determined maximum current. The respective socket comprises identification elements that are adapted to communicate or to co-operate with an electric plug so as to generate a pilot signal that is representative of the maximum current of the electrical signal that can be delivered by the socket outlet without being damaged. The electric vehicle can then adjust the value of the current that the battery of the vehicle may draw from the socket outlet for charging purposes, in order to avoid exceeding the maximum-current value. The pilot signal is a binary signai, in that the presence of the pilot signal issued by the socket outlet indicates that the socket outlet is adapted to supply a high current up to 16 A. The absence of a forwarded pilot signal or a pilot signal equal to zero indicates that the socket outlet is a standard socket outlet that is not certain to be capable of delivering current that is greater than 8 A without being damaged. When the electric plug of the battery of the electric vehicle forwards a pilot signal indicating that the socket outlet is adapted to deliver a current of 16 A, the battery is charged under optimized conditions and the vehicle draws a charging current of 14 A for the usual charging duration. If the electric plug that connects the battery of the electric vehicle to the socket outlet forwards a pilot signal indicating that the socket outlet is not certain to be capable of delivering a current of 16 A, then the battery of the vehicle draws a current that is less than 18 A, equal to 8 A for a duration that is longer than the usual charging duration, so as to charge the battery, without damaging the socket outlet. The vehicle thereby optimizes its charging time as a function of the socket outlet to which it is connected, without putting the installation in danger.

Despite developments as the above described there is still a need for further improving the charging systems for electric cars.

As the market of electric cars increases steadily and in some countries even explosively, so does the occurrence of so-called men-made local electrical solutions in the homes. That is exactly the area where the earlier described technology may still fail. For instance, once might have an electric plug having the pilot signal (i.e. the presence of a magnet), saying that it can deliver 16 A without getting damaged, while all the other parts of the electrical system from the main box, fuse box, residua! current detector, including ail the electric wires in between those parts, are not designed for that current level. This problem is exactly where the current invention kicks in as will be explained in the summary of the invention.

The invention has for its object to remedy or to reduce at least one of the drawbacks of the prior art, or at least provide a useful alternative to prior art.

The object is achieved through features, which are specified in the description below and in the claims that follow.

The invention is defined by the independent patent claims. The dependent claims define advantageous embodiments of the invention.

In a first aspect the Invention relates to a charging system for charging an electric vehicle. The charging system comprises a charging unit for being coupled to a battery unit of the electric vehicle, and an electric plug connected to the charging unit. The system further comprises an electric socket for receiving the electric plug and for being coupled to a mains network for receiving power therefrom. The system further comprises a socket identifier for transmitting a socket Identification signal quantifying the maximum allowable current for the electric socket, and a socket identifier reader for determining the maximum allowable current. The charging unit is configured for keeping the charging current at the maximum allowable current during charging. The socket identifier has been certified and authenticated by an authorized person, such as an electrician, in order to ensure that the charging system is able to deliver the maximum allowable current without resulting in damage.

The effects of the system for monitoring in accordance with the invention are as follows. As already mentioned there is an increasing occurrence of so-called men-made local electrical solutions in the homes. That is to say that, despite the regulations for electric circuitry which states that all electric circuitry in a home needs to be approved and certified by an authorized person such as an electrician, more people create their own systems, which increases the risk of damage and fire in the houses. The earlier discussed solution from US2014/0120764A1 does not avoid this risk, if one manages to mount the electric socket themselves, having the pilot signal for 16 A, while the rest of the electric system has not been adapted to 18 A, there Is an increased risk of personal injury, physical damage and fire in the home. The charging system in accordance with the invention solves this problem by making sure that the socket identifier has been certified and authenticated by an authorized person. Moreover, if this cannot be confirmed the whole system will operate at a lower current {optionally the lowest charging current) during charging. There is different ways of achieving this effect as wii! be illustrated in the discussion of the embodiments, it must be explicitly mentioned here that the prior art solution of US2014/0120764A1 only checks for the presence of the signal, which is not enough to establish that the signal has been certified and authenticated by an authorized person.

In order to better understand the invention a few terms are further defined hereinafter.

Where this description refers to certification and authentication of the socket identifier this is to be interpreted as the presence of evidence (or at least show that it is very likely) that an authorized person has actually verified and certified the charging system. This goes beyond the solution of the prior art, wherein the mere presence of a signal (i.e. a magnet in the socket) determines whether the system will charge at a high current. The mere presence of such magnet does not prove that the system has been verified and certified, i.e. any person could have installed this magnet without having verified the system and without being authorized to do so. in an embodiment of the charging system of the invention the socket identifier is provided as an external component to the electric socket. This embodiment opens up the possibility for the socket identifier to be an ad-hoc provided device that is mounted by an authorized person, after he or she has verified and approved the system. Then, in some embodiments, the provision of the socket identifier may be seen as the certification and authentication of the socket identification signal. This embodiment may be advantageously combined with other embodiments, which will further improve the system. Preferably, such external component is mounted such that it cannot be easily removed, for instance not without having tools which are normally only available to the authorized person. in an embodiment of the charging system of the invention the socket identifier is configured and mounted such that an attempt to remove it results in destruction of the socket identifier. Once an authorized person has provided the socket identifier to the electric plug, it may obviously be tempting for people to try to get this identifier in order to place it elsewhere. This embodiment conveniently prevents that to happen, because an attempt to remove the socket identifier will result in the destruction thereof. A possible implementation is to use an RFID tag which is mounted to the respective surface with strong glue, which is much stronger than the mechanical strength of the RFID tag (destroying one or more vital parts in the removal process, hence rendering it useless after removal). Such RFID tags are well known in the common domain, In an embodiment of the charging system of the invention the socket Identifier is provided as an insertable component in the electric socket. The insertion by the authorized person may be carried out such that it is Irreversible. This system can be further improved when the insertable socket identifier is configured for working with the respective electric socket only (for instance by giving that a unique ID), so that, if it is removed it will be deactivated.

In an embodiment of the charging system of the invention the socket identifier is repiaceab!e OR reprogrammable. This embodiment is advantageous, because it opens up the possibility for the authorized person to re-access the system and provide a different certification, with either a higher current level or a lower current levei, in an embodiment of the charging system of the invention the socket identification signal quantifies the maximum allowable current with at least three different values. This embodiment is advantageous in the situation, where the electric system is not suitable for the highest current, but still for a reduced current being higher than the lowest current. After verification and approval by the authorized person the result may then be a socket identification signal, which indicates an intermediate value, for instance 12A in between 8A and 16A if these are the extremes. It must be noted that in this embodiment the charging unit is preferably configured to charge at a!i these different levels.

In an embodiment of the charging system of the invention the socket identification signal quantifies the maximum allowable current within a predefined range of current levels. This embodiment builds further on the previously discussed embodiment. Instead of discrete levels one may also implement the charging system such that there is a whole range of levels at which the charging may be carried out. St must be noted that in this embodiment the charging unit is preferably configured to charge at the whole range of levels.

In an embodiment of the charging system of the invention the socket identifier reader is configured for verifying if the socket identification signal of the socket identifier has been certified and authenticated. There is different ways of carrying out this verification.

In an embodiment of the charging system of the invention the socket identifier signal comprises a person identification part identifying the authorized person who authorized and certified the socket identification signal, in this embodiment the certification and authorization process is effectively stored in the socket identifier, such that it is known who certified and authorized the electric socket.

In an embodiment of the charging system of the invention the person identification part forms part of the socket identification signal. This embodiment provides a higher level of security, because the person identification may be read out together with the socket identification signal. Expressed differently, the personal stamp of the authorized person is literally in the socket identification signal. In an alternative embodiment of the charging system of the invention the person identification part is transmitted as a separate signal. It is understood that the socket identifier reader is then preferably also configured to verify said separate signal in addition to the socket identification signal

In an embodiment of the charging system of the invention the socket identifier signal is configured for quantifying the maximum allowable current for the electric socket in a dynamic manner. This embodiment is may be advantageous in case of dynamic circumstances, wherein the maximum allowable current to be delivered is variable, because of other reasons than risk of destruction, fire or damage. For instance, in case the power grid to which the charging system is highly loaded, there coufd be a need to reduce the maximum allowable current. Alternatively, the maximum allowable current to be delivered may be dynamic in that the electric system is subject to change due to aging and wear for example, i.e. the maximum allowable current may need to be reassessed and revalidated and authenticated at a later stage.

In an embodiment of the charging system of the invention the socket identifier reader is placed in the charging unit of the vehicle. Whereas the prior art solution put a sensor in the plug, in this embodiment the plug may be a conventional plug, while the socket identifier reader resides in the charging unit, yet still being in close proximity with the socket identifier.

In an embodiment of the charging system of the invention the socket identifier reader comprises an antenna that is integrated with electric wiring between the charging unit and the electric plug. This embodiment effectively exploits the wiring between the charging unit in the electric plug, which will improve the sensitivity of the socket identifier reader. The socket identifier may be an RFiD tag in this embodiment and the socket identifier reader may comprise an RFiD tag reader. However, the invention is not limited to such technology. Different RF, magnetic, optical, audio signalling technologies using open and/or proprietary communication protocols can be used for all embodiments, for example Bluetooth, Bluetooth Low Energy, ZigBee, Z-wave, Wi-Fi, NFC, Ant and others.

The invention further relates to each of various components within this system as such, which have been adapted for the purpose of authentication. This will be further explained in the detailed description of the figures. While the charging system of the invention comprises different parts (plug and socket, socket identifier and socket identifier reader) to achieve a certain effect, still each of said parts may be sold independently of the other. Therefore, the invention also resides in each of the separate entities as such.

In a second aspect the invention relates to the electric socket for use in the charging system of the invention.

In a third aspect the invention relates to the electric plug for use in the charging system of the invention.

In the following is described examples of preferred embodiments illustrated in the accompanying drawings, wherein: Fig, 1 shows a charging system as known from the prior art;

Fig. 2 shows another charging system as known from the prior art;

Fig. 3 shows a charging system in accordance with a first embodiment of the invention;

Fig. 4 shows a charging system in accordance with a second embodiment of the invention;

Fig. 5 shows a charging system in accordance with a third embodiment of the invention;

Fig, 6 shows a charging system in accordance with a fourth embodiment of the invention;

Fig. 7 shows a charging system in accordance with a fifth embodiment of the invention;

Fig. 8 shows a charging system in accordance with a sixth embodiment of the invention;

Fig. 9 shows a charging system in accordance with a seventh embodiment of the invention;

Fig. 10 shows a socket identification signal in accordance with another embodiment of the invention;

Fig. 11 shows a secure identification signal in accordance with yet another embodiment of the invention, and

Fig. 12 shows a secure identification signal in accordance with yet another embodiment of the invention.

The description herein after elaborates on the complete charging system for an electric vehicle. Yet, it must be understood that this system comprises various parts, which may be sold as separate entities commercially. The claims have therefore also been directed to these parts as such.

Fig. 1 shows a charging system 100 as known from the prior art. The figure shows that the system 100 comprises two parts A, B. The first part A is the electric installation in a home, which is the current-providing side of the system 100. Furthermore, the second part B is the electric vehicle charging assembly, which is the current-demanding side of the system 100. The interface between the first part A and the second part B is formed by an electric socket 50 and electric plug 60, which are to be complementary such that the etectric plug 60 can be inserted into the electric socket 50 for establishing an electric connection there between. All this is considered to be well known to the person skilled in the art of charging systems for electric vehicles.

The etectric plug 60 forms part of an electric vehicle charging assembly 80, which further comprises a electric vehicle supply equipment 70 (EVSE), which is eSectricaliy connected to the electric plug 60 via electric wiring 65, An output of the EVSE 70 is coupled to the electric vehicle 999, which batter(y)(!es) is/are to be (re)eharged. The electric vehicle 999 in this example is an electric car, but this could be virtually any kind of electric vehicle, such as but not limited to, an electric bicycie, an electric scooter, an electric motorcycle, or an electric transport vehicle such as a Seg- way™ or any other kind personal transport vehicles. Yet in other embodiments the charging system 100 may also be used for supplying to high-current electric appliances such as electric heater and cooking appliances (such as furnaces, ovens, and stoves), water heating appliances (such as electric boiler heaters). The commonality between these applications is the fact that they all need high currents, but at the same time they all stili function when receiving lower currents.

The electric socket 50 is generally provided on a wall or ceiling 40 and connected with the mains network of the respective home (not shown). The invention is not limited to a specific configuration of such mains network, yet a typical mains network comprises the following parts. First of all there is the main connection 5 with the main supply (i.e. a power plant) outside the respective home. This main connection 5 typically comes in a main junction box 10, The main junction box 10 is typically electrically connected to a fuse box 20 via further electric wiring 15. The fuse box 20 is typically electrically connected to a residual current detector (RCD) 30 via further electric wiring 25. The RCD 30 is typicaiiy coupled (via further electric wiring 35) to the mains wiring network in the home, including the electric socket 50.

The charging system 100 as illustrated in Fig. 1 is capable of providing a predefined maximum current to the electric vehicle 999 without getting damaged or resulting in fire. This predefined maximum current is factually determined by the weakest link in the system. Obviously, the electric vehicle charging assembly B may be designed to be able to charge at very high currents (18A, 25A or even higher), yet most homes have 10A (or 8A) or 16A (or 14A) current limitations. Thus, theoretically, it could be that the appliance 999 draws a higher current than the electric socket 50 can provide in a safe manner (I.e. the electric plug is plugged into the socket of a wrong type having too low current providing capacity). A further problem may arise when the owner of the house starts to create his/her own electric networks. In such scenario the electric vehicle charging assembly B might draw too much current than what is safe for the electric installation in the home A.

It must be noted that a charging system (also in accordance with the invention) may have fewer components than drawn in Fig. 1.

Solutions to these problems have been thought and build into the charging system 100. Fig. 2 shows such charging system 200 as known from the prior art, for instance from

US2014/0120784A1. This figure will be discussed in as far as it differs from Fig. 1. In Fig. 2 the electric socket 50 has been provided with a signal generator 52 that generates and transmits a pilot signal. This pilot signal is subsequently received by a sensor 62 that is provided within the electric plug 60. When the pilot signal is present the electric vehicle 999 is charged at a high current, i.e. 16A (or 1 A). When the pilot signal (for example because the signal generator 52 is missing) is not present the electric vehicle 999 is charged at a low current, i.e. 10A (or 8A). As nobie as the solution of the charging system 200 of Fig. 2 may seem It still suffers from severe drawbacks. For instance, the system may still be buiit by an amateur or non-authorized person, such that, despite the presence of the signal generator 52 in the electric socket 50, the rest of the system 200 is not designed for the high current (of 18A (or 14A) for example). This is where the current invention provides a solution as will be obviated in the description hereinafter.

The invention, despite the various quite different embodiments, may be summarized as being an electric charging system, wherein there is provided a socket identifier that has been certified and authenticated by an authorized person, such as an electrician, In order to ensure that the charging system is able to deiiver the maximum allowable current without resulting in damage, wherein the charging system is designed to operate at a lower current during charging when the socket identification signal has not been certified and authenticated.

Fig. 3 shows a charging system 300 in accordance with a first embodiment of the invention. This embodiment will be discussed in as far as it differs from Fig. 2. The electric socket 50 has been provided with a tamper-safe, certified and authenticated socket identifier 54 on an exterior side thereof (but it could be provided on an interior side as well). This socket identifier 54 generates and transmits a socket identification signal 54S, which is subsequently detected by a socket identifier reader 74, which is provided within the EVSE 70 in this embodiment- The socket identifier 54 may be an RFID tag, which is mounted on a surface of the electric socket 50 with a strong glue, while the substrate of the tag 54 (carrying its antenna) is very weak. In this way, it is virtually impossible to remove the tag from the electric socket 50 without damaging its internal circuits.

The socket identifier 54 has been mounted on the electric socket 50 by an authorized person, such as an electrician, but only after that the system has been verified by him/her. The consequence of this embodiment is that the RF-ID cannot be moved by unauthorized persons. Moreover, the system is preferably configured or programmed such that the socket identifier reader 74 will only work with this particular socket identifier 54 (using its unique ID for example). In the absence of this certificated and authorized socket identifier, the system will only charge at its lowest charging current, for instance 8A or even lower, and in other embodiments even not at all.

Alternatively or in addition, the socket identifier 54 is such that If can only be activated by an authorized person, i.e. it will not generate and transmit the socket identification signal 54S after activation. In other embodiments the location, date and installer's name or ID are stored inside the socket identifier 54 or transmitted via the socket identification signal 54S.

Alternatively or in addition, the socket identification signal 54S can be only set by the authorized person. Alternative or in addition, the socket identification signal 54S can be programmed so as to indicate the maximum current level in more than two different levels, or a range of levels. Alternatively or in addition, the socket identification signal 54S can be dynamically programmed and re- programmed by the authorized person. Alternatively or in addition, the socket identifier may be an active tag (not only passive, meaning that it has its own power supply and/or energy storage, such as a battery) for allowing communication with other parts of the electrical system, such as a smart house control system, a router, a repeater or other EVSE's or other active wall sockets.

Fig, 4 shows a charging system 400 in accordance with a second embodiment of the invention, This embodiment will be discussed in as far as it differs from Fig. 3. Instead of the tamper-safe certified and authorized socket identifier 54, there is provided an insertable socket identifier 54'. The insertabiiity may be such that the socket identifier 54 may not be removed at ail, or may not be removed without proper tools that are only possessed by authorized person.

Fig, 5 shows a charging system 500 in accordance with a third embodiment of the invention. This embodiment will be discussed in as far as it differs from Figs. 3 or 4. in this embodiment the socket identifier has been provided with as an externa! component 54". Such location may facilitate pro- grammability and/or replaceabi!ity of the socket identifier 54".

Hereinafter, some more sophisticated and intelligent embodiments of the charging system are discussed.

Fig. 8 shows a charging system 600 in accordance with a fourth embodiment of the invention. This embodiment differs from the previous embodiments in that the certification and authorization has now also been done for the other parts of the electric installation in the home A. In fact each component 10, 20, 30 may be provided with a respective certified and authenticated identifier 14, 24, 34 in accordance with the invention. Each of the identifiers 14, 24, 34 in the components is configured for generating and broadcasting a component identifier signal, which indicates the maximum allowable current it may be safely provide. Alternatively, it may be a subset of the components shown in Fig. 6 having such functionality, it goes without saying that ail of these component identifier signals may be subsequently read out or sensed by the socket identifier reader 74 (or another reader) such that the electric vehicle charging assembiy 80 knows the electric properties of each of the components, and then decides with what current level it wi!i charge the eiectric vehicle 999. it may be advantageous and even recommendatory to choose the lowest of the maximum current levels indicated by said identifiers 14, 24, 34, 54", The socket identifier 54" in Fig, 6 may also be chosen as shown in Figs. 3, 4 or 5.

A drawback of the embodiment of Fig. 8 is that there is no monitoring of the state of the electric wiring between the components 10, 20, 30, 50, which might also suffer from current level limitations. This problem may be solved with the embodiment of Fig. 7, which shows a charging system 700 in accordance with a fifth embodiment of the invention, in this embodiment temperature sensors 11 , 13, 21 , 23, 31 , 33, 41 have been implemented at the terminals of said components 10, 20, 30, 50. In case the current carrying capacity of the respective wirings 5, 15, 25, 35 is too low in view of the charging current being used, the respective wirings will typically heat up. Such temperature rise may then be detected by the temperature sensors of Fig, 7, and subsequently, the respec- five component may then broadcast a respective component identifier signal indicating a lower maximum current.

Fig. 8 shows a charging system 800 in accordance with a sixth embodiment of the invention. This figure illustrates that the embodiments of Figs. 3 to 7 may be further sophisticated in that the respective electric wirings between the components are provided with communication functionality as illustrated by the dashed arrows in Fig. 8.

Fig, 9 shows a charging system 900 in accordance with a seventh embodiment of the invention. This figure illustrates that the embodiments of Figs. 3 to 8 may be further sophisticated in that a subset or each of the components of the charging system 900 are capab!e of communicating with a server or service in the cloud 1000 as illustrated by the dashed arrows in Fig, 9.

The embodiment of Figs. 3 to 9 may have further variations. For instance, the antenna of the socket identifier reader 74 (for instance when an RFID tag is used) may be integrated in the wiring 65 between the electric plug 60 and the EVSE 70. This will improve the sensitivity of the socket identifier reader 74. in a further variation the socket identifier reader may be fully placed within the electric plug 60. In a further variation the functionality of the EVSE 70 has been fully integrated in the electric plug 60 or in the electric vehicle 999.

Fig. 10 shows a socket identification signal 54S in accordance with another embodiment of the invention. This figure illustrates that the socket identification signal 54S may comprise different parts, for instance a header part HP, a socket identification part SIP and a tail part TP, The header part HP and the tail part TP may be necessary in order to enable wireless communication (in accordance with a communication protocol) between the socket identifier 54, 54', 54" and the socket identifier reader 74. The identification of the properties, such as the maximum current without getting damaged, of the charging system may be encoded in the socket identification part SIP. Obviously, the socket identifier reader 74 must be designed such that if can read the socket identification signal 54S.

Fig. 1 1 shows a secure identification signal 54S" in accordance with yet another embodiment of the invention, in this embodiment the identity of the authorized person has been encoded in a person identification part PIP in the secure identification signal 54S'. Fig, 12 shows an alternative secure identification signal 54S" in accordance with yet another embodiment of the invention, wherein the person identification part PIP forms part of a separate signal having its own header part HP and tail part TP. Obviousiy, the socket identifier reader 74 must be designed such that it can secure read said socket identification signals 54S', 54S".

There are many variation possible in the charging system for the invention. First of all, it must be borne in mind that, even though all examples given in the figure description are related to the charging of electric cars, the invention is also applicable to other electric appliances. Basically, the invention is applicable to any electric appliance that may draw large currents from the power grid during charging or operation. A non-exhaustive iist of such applications comprises electric heater and cooking appliances (such as furnaces, ovens, and stoves), water heating appliances (such as electric boiler heaters). The invention is particularly useful, but not limited to, applications, which can charge or operate at lower currents as we!!.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. Use of the verb "comprise" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the device claim enumerating several means, several of these means may be embodied by one and the same item of hardware.