BACKGROUND OF THE INVENTION

1. Field of the Invention

[0001] The present invention relates in general to lighting systems and, more particularly, to a method and apparatus for producing colors and for reducing or eliminating other visible colors in lighting systems.

2. Description of the Related Art

[0002] As can be understood, there are numerous reasons to reduce power consumption of a lighting or other electrical system. The benefits include reduced power costs to the user and benefits to the environment. In conjunction with this system, there are numerous reasons to produce specific colors or reduce or eliminate other visible colors in a lighting system. The benefits include the ability to display a particular color with reduced power costs to the user and benefits to the environment.

[0003] While it may be desirable reduce or eliminate other visible colors in a lighting system, it is preferred to not reduce or hinder operation of the electrical system. By way of example, a lighting system can be configured to reduce or eliminate certain visible colors in a low power environment, but reducing power consumption could undesirably reduce the light output of the lighting system. The lighting system was likely installed and designed for a predetermined amount of input power or voltage and hence, reducing the amount of the voltage defeats the purpose of the lighting systems.

[0004] It is known, however, that certain types of electrical systems can be provided with less power without hindering operation. In the case of lighting systems, it is known that high intensity discharge (HID) and fluorescent lighting systems can be operated at a lower voltage after operation for a short time at full power. Power savings through dimming can be realized without an appreciable amount of reduced light output.

[0005] There are many different situations for which producing a particular color may be advantageous. For example, a grocery market might want to shine a red color on its meat products to increase its desirability to a consumer. However, there exists a need to produce a specific color while taking advantage of the reduced power benefits outlined above.

SUMMARY OF THE INVENTION

[0006] In one embodiment, the present invention is a power control system, comprising a power reduction module operable to reduce power to a connected load, a switching module operable to selectively transfer power directly to the load or to the power reduction module, a frequency module coupled between the harmonic reduction module and the load, a harmonic reduction module connected to an output of the power reduction module for reducing signal harmonics from power transferred to the frequency module, a controller linked to the switching module and to the frequency module to provide control signals, a resistor coupled between the switching module and the power reduction module, and a resistor voltage monitor coupled between the switching module and the resistor, wherein the resistor voltage monitor measures a voltage across the resistor and sends voltage measurement data to the controller.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The above and other aspects, features, and advantages of certain exemplary embodiments of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0008] FIG. 1 illustrates a block diagram of an example power control system;

[0009] FIG. 2 illustrates a three phase application of an example power control system. DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0010] The present invention is described in one or more embodiments in the following description with reference to the Figures, in which like numerals represent the same or similar elements. While the invention is described in terms of the best mode for achieving the invention's objectives, it will be appreciated by those skilled in the art that it is intended to cover alternatives, modifications, and equivalents as can be included within the spirit and scope of the invention as defined by the appended claims and their equivalents as supported by the following disclosure and drawings. Power control systems such as those used in connection with the present invention are disclosed in U.S. Pat. No. 7,417,410, the entire contents of which are hereby incorporated by reference.

[0011] Many of the functional units described in this specification have been labeled as modules, in order to more particularly emphasize their implementation independence. For example, a module can be implemented as a hardware circuit comprising custom VLSI circuits or gate arrays, off-the-shelf semiconductors such as logic chips, transistors, or other discrete components. A module can also be implemented in programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices or the like.

[0012] Modules can also be implemented in software for execution by various types of processors. An identified module of executable code can, for instance, comprise one or more physical or logical blocks of computer instructions which can, for instance, be organized as an object, procedure, or function. Nevertheless, the executables of an identified module need not be physically located together, but can comprise disparate instructions stored in different locations which, when joined logically together, comprise the module and achieve the stated purpose for the module. [0013] Indeed, a module of executable code can be a single instruction, or many instructions, and can even be distributed over several different code segments, among different programs, and across several memory devices. Similarly, operational data can be identified and illustrated herein within modules, and can be embodied in any suitable form and organized within any suitable type of data structure. The operational data can be collected as a single data set, or can be distributed over different locations including over different storage devices, and can exist, at least partially, merely as electronic signals on a system or network.

[0014] Reference throughout this specification to "one embodiment," "an

embodiment," or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment or example of the present invention. Thus, appearances of the phrases "in one embodiment," "in an embodiment," and similar language throughout this specification can, but do not necessarily, all refer to the same embodiment.

[0015] Reference to a signal bearing medium can take any form capable of generating a signal, causing a signal to be generated, or causing execution of a program of machine- readable instructions on a digital processing apparatus. A signal bearing medium can be embodied by a transmission line, a compact disk, digital-video disk, a magnetic tape, a Bernoulli drive, a magnetic disk, a punch card, flash memory, integrated circuits, or other digital processing apparatus memory device.

[0016] Reference to service can include any conceivable service offering associated with analysis, design, implementation, or utilization of the disclosed apparatus, system, or method. A service can additionally include but is not limited to rental, lease, licensing, and other offering, contractual or otherwise, of hardware, software, firmware, network resources, data storage resources, physical facilities, and the like. Services can additionally include physical labor, consulting, and other offerings of physical, intellectual, and human resources.

[0017] The schematic flow chart diagrams included are generally set forth as logical flow chart diagrams. As such, the depicted order and labeled steps are indicative of one embodiment of the presented method. Other steps and methods can be conceived that are equivalent in function, logic, or effect to one or more steps, or portions thereof, of the illustrated method. Additionally, the format and symbols employed are provided to explain the logical steps of the method and are understood not to limit the scope of the method. Although various arrow types and line types can be employed in the flow chart diagrams, they are understood not to limit the scope of the corresponding method. Indeed, some arrows or other connectors can be used to indicate only the logical flow of the method. For instance, an arrow can indicate a waiting or monitoring period of unspecified duration between enumerated steps of the depicted method. Additionally, the order in which a particular method occurs can or can not strictly adhere to the order of the corresponding steps shown.

[0018] Furthermore, the described features, structures, or characteristics of the invention can be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided, such as examples of programming, software modules, user selections, network transactions, database queries, database structures, hardware modules, hardware circuits, hardware chips, etc., to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention can be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well- known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention. [0019] A method and apparatus providing a specific frequency to a load is disclosed. In the embodiments described below, the load can include a light or lighting system. The method and apparatus for control power described can control a variety of lighting systems, including HID, low-pressure sodium, fluorescent, iridescent, metal halide, mercury vapor, and high-pressure sodium systems. However, the method and apparatus described below can be applied to any number of situations where applying a frequency to a load is desired.

[0020] The components in HID light bulbs can be made of different materials or ratios depending on who manufactures it. For example, materials can include nickel-coated iron , stainless steel tungsten , zirconium, Argon, vanadium compounds, magnesium germinate phosphor, mercury, Krypton-85, thorium, thorium iodide and cadmium kaolin clay.

[0021] When electricity is applied, the various substances emit a spectrum of light, the sum total of which the eye converts to a color. The electrons move to an outer valence when the electricity is applied, and then emit a particular frequency when they drop down to their normal orbit after the electricity is removed. Electricity can be applied at 60 cycles per second or 50 cycles per second, or at other particular frequencies. The frequency the electrons emit is characteristic of the substance used in the bulb. Thus, the frequency produces the color spectrum.

[0022] Turning to FIG. 1, an example block diagram of a power control system 100 is shown. An input 102, in one embodiment, connects to a switching module 104. The input 102, according to an embodiment, receives an input power supply to be provided to a load 112. In addition to the switching module 104 receiving an input power supply with a line voltage, the switching module 104 also receives a low voltage control input from a controller device 106. Switching module 104, as illustrated, is connected to a power reduction module 108, a harmonic reduction module 110, and to a frequency module 126. In one embodiment, the frequency module 126 is connected to the load 112 and receives a low voltage control input from a controller device 106. The opposing side of the load 1 12 connects to a ground or neutral 116. In one embodiment, frequency module 126 produces a specific color by generating a specific frequency that will cause the load to emit a subset of electrons. Each color represents a subset of electrons that were emitted as light. The system described in FIG. 1 can be configured in single or three phase. As such, ground or neutral 1 16 can also be configured to be a secondary input 102 for a particular application.

[0023] Switching module 104 can include any type of device configured to switch power output between conductors 1 14 and 1 15. In various examples the switching module 104 includes a relay, switch, contacts, resistors, capacitors, or any other type of switching system. The switching of the power or signal in the input 102 can occur instantaneously or close thereto, concurrently, or as part of a progressive fade in transfer of the output between conductors 114 and 115. Hence, for a period, both conductors 1 14, 1 15 may be energized. The controller 106, which connects to switching module 104 and provides power to frequency module 126, is configured to control the time at which the switching module 104 switches/toggles and the rate at which switching occurs. Controller 106 can include a timer which operates based on the time of day or based on other factors. Controller 106 can also include a variety of programmable devices or components or can be externally connected to a remote computer system, as will be seen.

[0024] As discussed above, the load 1 12 can include any type of load 112 whose supplied power could be reduced with a corresponding degree of savings while the overall operational integrity of the load 112 is maintained. In one example, the load 112 includes a lamp, lamp fixture, or lighting system. To reduce or otherwise modify power consumption by the load 1 12, the example of FIG. 1 as shown includes the power reduction module 108 and the harmonic reduction module 110. The power reduction module includes any type of system or device capable of reducing the amount of power provided to the load 112 w ^r hen power is diverted by the switching module 104 to travel through the power reduction module 108. In one example, the power reduction module 108 includes a commonly obtained step- down transformer. In other examples, power reduction module 108 includes a transformer, motor controller contactors, resistors, timers, general duty delay, switches, and lights. Power reduction module 108 can also include various components such as capacitors, resistors, variable or programmable capacitors, solid state contactors, and transistors.

[0025] Power control system 100 includes a harmonic reduction module 110. The harmonic reduction module 110 can perform signal processing on the output of the power reduction module 108 to provide an improved signal to the frequency module 126. In one example, the harmonic reduction module 110 includes a pass filter having a cut off frequency selected to remove unwanted harmonics or frequency components. Harmonic reduction module 1 10 can include a capacitor sized to remove unwanted signal components. In some instances, failure to remove unwanted frequency components from the signal after power reduction can result in undesirable operation of the load 1 12. Power reduction module 108 and harmonic reduction module 110 can connect to ground or neutral 116 as necessary to achieve desired results as previously described.

[0026] In can be appreciated that the frequency module 126 is applied after the power reduction module 108 because sending specific frequencies through the transformer can cause harmonics which are detrimental to light bulbs and other items located on the same circuit as the light bulbs.

[0027] In one example, input 102 includes a 60 hertz power signal and load 112 includes HID-type lamps or fixtures. After an initial warm up phase, the power provided on the input 102 can be switched from directly going to the frequency module to run through the power reduction module 108. Reduction of the voltage by the power reduction module 108 can introduce harmonics into the signal provided to frequency module 126. As a result of the harmonics, the level of power provided to the frequency module 126 can undesirably drop below the minimum required power level necessary to maintain operation of the load 112. Inclusion of harmonic reduction module 1 10 helps to alleviate the harmonics and ensure proper and reliable operation of the load 112.

[0028] Power control system 100 includes additional components. A resistor voltage monitor 1 18, low voltage monitor 120, and voltage savings monitor 122 are illustrated. As shown, a sensor lead 1 17 is connected between resistor voltage monitor 1 18 and conductor 115. Additionally, a sensor lead 119 is shown connected between low voltage monitor 120 and conductor 115. Monitors 1 18, 120, 122 are intended to be powered by a separate power supply than from input 102. Monitors 118, 120,122 form an external system apart from the main power conducting channels 1 14 and 1 15. The monitors work independently to measure operational parameters of the system 100 and provide information to controller 106 or elsewhere. In the event of a power disruption in system 100 (e.g., a loss of input 102 power), monitors 1 18,120 and 122 can be provided with a battery backup, an uninterrupted power supply (UPS) or similar means to continue to operate and relay operational information to the appropriate destination.

[0029] Monitors 118,120, 122 can be connected to controller 106 by a signal bearing medium which can carry information such as a control signal between monitors 118, 120, 122 and controller 106. Additionally, monitors 1 18, 120, 122 can include an input-output (I/O) port or similar means to communicate with an external computer system (not shown). The external computer system can be coupled between the controller 106 and the various monitors 1 18,120, 122.

[0030] Resistor voltage monitor 1 18 and low voltage monitor 120 add an additional level of reliability to the operation of power control system 100. Resistor voltage monitor 118, low voltage monitor 120 and voltage savings monitor 122 can be configured to work in conjunction with controller 106 by providing a stream of data which discloses the operating parameters of the power control system 100 to controller 106 or to an external computer system. Depending on the nature of the data received, controller 106 can implement predefined operating procedures of the system 100 or can be instructed to implement the predefined operating procedures through an external system.

[0031] In one example, resistor voltage monitor 1 18 monitors the voltages across a resistor or set of resistors which are incorporated into the system 100. If resistor voltage monitor 118 detects the appropriate potential across the resistor(s) in a preliminary first step, resistor voltage monitor 118 can then notify controller 106 or an external system that the system 100 is able to begin implementing the power reduction process. Low voltage monitor 120 similarly monitors voltages as part of the overall system 100. If a situation arises where voltages drop to an undesired low level, low voltage monitor 120 can act to notify controller 106 or an external system of the problem. As a result, controller 106 can implement a predefined/preprogrammed recovery procedure which is intended to allow the voltage(s) across the load 112 to increase to an appropriate level to ensure operability of the load 112.

[0032] Voltage savings monitor 122 also can work in conjunction with controller 106 or a similar component in the system 100. In one example, voltage savings monitor 122 monitors the actual voltage(s) being supplied to the load 1 12 and compares the actual voltage with a predetermined/preprogrammed line voltage as supplied to input 102 to determine a difference voltage. Over a period of time, the difference voltage can be multiplied with the time period and a cost coefficient of electricity to determine the overall monetary savings as a result of the implementation of system 100.

[0033] Consider an example method A of operation of the method and apparatus described herein. Method A begins when the operation provides power to the power control system 100. Providing power may occur by actuating a switch or relay as part of switching module 104. It may be desirable to locate a relay or switch between the power source 102 and the transformer or other power reduction modules 108. As a result, power may not be continually provided through conductor 115. In some configurations the transformer or other power reduction modules 108 may draw power even when the load 112 is not energized. Consequently, disconnecting the transformer or other power control devices from the power source 102 during periods when the load 112 is not in use may result in additional power savings.

[0034] As a next step in example method A, the operation provides full power to the load 112 to initiate desired operation of the load 112. The load 112 generally requires full power during an introductory start-up period. After the introductory start-up period the power, i.e. voltage or current, supplied to the load 1 12 may be reduced without significantly affecting operation of the load 112. Timing or monitoring of the load 112 or some attribute of the load 112 may occur to determine when operation power provided to the load 1 12 may be reduced. In addition, monitors 1 18 or 120 can monitor the operational health of the system 100 to determine whether it is safe to proceed with a power reduction operation as is now described.

[0035] As a next step, the operation checks voltage across resistors located as part of system 100 using the resistor voltage monitor 1 18. If a voltage is seen across the resistors, controller 106 is notified by resistor voltage monitor 1 18 that the system 100 is operational and able to begin the power reduction operation or process. Controller 106 can then begin diverting power as provided directly to the load to a power reduction module 108 and/or harmonic reduction module 110 and/or the frequency module 126. The diversion of power may occur rapidly or over a period of time to achieve a smooth transition that does not interfere with desired operation of the load. One or more circuits or power supply systems may be introduced to achieve a desired transition. [0036] As a next step, a harmonic reduction operation occurs by harmonic reduction module 1 10 to reduce harmonics that may be created by the power reduction step. In one embodiment, signal aspects other than harmonics are reduced or eliminated. As a next step, a reduced amount of power is provided to the frequency module 126 as compared to the amount or level of power provided at a previous step in the operation. The frequency module 126 can send sends a frequency to the load 112 in either continuous or sporadic fashion. The load 112 continues to operate in a desired manner even at reduced power level and the load 112 operates consistently as a result of the harmonic reduction or other signal improvement that occurs. This is but one possible method of operation that benefits from the harmonic reduction operation or other power signal modification methods discussed herein. It is contemplated that one of ordinary skill in the art may derive other methods of operation that do not depart from the scope of the invention.

[0037] FIG. 2 illustrates an example block diagram of a three-phase power control system 124. Power is supplied from a main power source 126. Four sets of relays, designated as Rl, R2, R3 and R4 are shown in various parts of the system 124. Relays Rl, R2, R3, R4 are shown connected to a controller 106. Again, controller 106 can include any hardware, software, or a combination of hardware and software implementations in order to cause relays Rl, R2, R3, R4 to function. Relays Rl, R2 are shown connected in parallel with main power source 126. A set of fuses 128, one for each phase, protects the input terminals to relays Rl. Resistor voltage monitor (RVM) 118 is shown connected to the output terminals of relays R2. Also connected to the output terminals of relays R2 are a set of resistors 130, again one for each phase. RVM 118 is also linked to controller 106 to send and receive operating information for system 126.

[0038] The output of a first tap 132 of a step-down transformer is connected to fuses 128. The output terminals of fuses 128 are connected to the input terminals of relays R3. Likewise, the output of a second tap 134 of the step-down transformer is shown connected to the terminals of relays R4. Also shown connected to the terminals of relays R4 is low voltage monitor (LVM) 120 with an accompanying connection to controller 106 and fuses 128. Connected to the junction of the terminals Rl, R2, R3, R4 is a harmonic reduction module (HRM) 110 with an accompanying connection to controller 106. VSM 122 makes a closed loop with the output terminals of HRM 110 to read a C-Type (CT) voltage and calculate voltage savings. VSM 122 also has a corresponding link with controller 106 to send information to controller 106 in order for the information to be displayed to a user. Frequency module 116 is shown connected to the output terminals of HRM 110, and load 112 is shown connected to the output terminals of load frequency module 116.

[0039] Relays Rl, R2, R3, R4 are shown as relays for purposes of understanding. Devices other than relays can be utilized including switches, magnetic contacts, manual switches, resistors, trisistors, capacitors, fuseblocks, and phase monitors. The first tap 132 and second tap 134 of the transformer comprise a first step-down transformer tap 132 and second step-down transformer tap 134 configured to step down or reduce the voltage provided at the first tap 132 or second tap 134 as compared to the voltage level at the power source 126. It is intended that a voltage level taken at the first tap 132 is generally higher than a voltage level taken at the second tap 134.

[0040] Controller 106 can include a programmable logic controller (PLC) or similar microprocessor-based industrial control system. Controller 106 can communicate with other process control components through various data links as part of system 100, system 126, or an external system, again as previously described. Hence, it is contemplated that controller 106 can include a local controller, a remote controller, or a combination of both local and remote controller systems. A remote controller portion can comprise a computer system located externally from system 124 in order to provide for redundancy, a similar benefit, or simply for ease of installation. Controller 106 can be used in process control for simple switching tasks, Proportional-Integral-Derivative (PUD) control, complex data manipulation, arithmetic operations, timing and process and machine control of system 100 or 126.

Controller 106 can provide power to frequency module 126.

[0041] An example implementation of controller 106 can include an accompanying graphical user interface (GUI) which can indicate operational information to a user. An associated GUI can include such devices as liquid-crystal display (LCD) screens, light- emitting diodes (LEDs) or similar visual and/or auditory components. A master override switch, master reset switch, or similar components can also be associated with controller 106 so that in the event of a power failure, the system 100 or 126 can be bypassed or shut down. The master override switch or reset switch can include a manual on/off function where a user can turn the system 124 off manually if desired.

[0042] Controller 106 can include various communications channels in order to provide notification to a user of the operational status of system 100. For example, a telephone link can connect controller 106 with an external communications network, computer system or similar. Controller 106 can use the telephone link to notify external customers in the event of a system 100 malfunction.

[0043] In contrast to earlier harmonic reduction systems that provided harmonic signal processing to balanced loads, HRM 110 allows system 100 or 124 to reduce power to both balanced and unbalanced loads. HRM 1 10 can be designed for specific load requirements. Any frequency cut-off point can be achieved through selection of the appropriate capacitor value. HRM 110 can comprise an active filter which uses various power electronics such as those illustrated in the example embodiment to reduce or cancel signal harmonics from the load(s) 112. [0044] During an operation of the power reduction system 124, LVM 120 can continuously monitor an output voltage being supplied to load 112 to ensure that the power is consistently being supplied to load 1 12. If the measured voltage drops to a level lower than a predefined level, LVM 120 can send the measured voltage data or a similar communications signal to controller 106 to notify controller 106 of the situation. Controller 106 (again, comprising a local controller, remote controller, or a combination of both local and remote controllers) can then take steps to increase voltage to the system.

[0045] Again, as previously described, the method and apparatus of power control exemplified in systems 100 and 124 can be applied to any number of situations where the power supply to a load is desired to be controlled. For example, a power control system can be implemented where the load 112 includes a heater for a plastic molding machine. In a typical scenario, the plastic molding machine can necessitate a higher amount of startup voltage and/or current to heat to a desired temperature. After the desired temperature is reached, however, it is not necessary to supply a continued amount of full voltage to the heater to maintain operation. A series of calculations which depend on various manufacturing parameters can be utilized to form a predetermined operation schedule which can be programmed into controller 106. As such, the controller 106 can operate relays Rl, R2, R3, R4 as necessary to cause the appropriate stepped-down voltage to reach the heater at the appropriate time in a manufacturing operation, yet save power by providing an overall reduced average voltage over time.

[0046] In a second example, load 112 can include a conveyor system for crushing rocks or a similar operation. Again, a much larger startup voltage is generally required to generate the necessary torque to the motors operating the conveyor belt. Once the startup torque is obtained and the motors are turning at the desired revolutions-per-minute (RPMs), the voltage applied to the conveyor motors can then be stepped-down to an appropriate operating voltage. Monitors 118 and 120 can be configured such that a sudden increase in the load (e.g., heavier rock or larger friction in the system) can be relayed to controller 106 in a matter of milliseconds or microseconds. Controller 106 can then quickly implement (again in a matter of fractions of a second) a predefined operational schedule which can include opening and closing relays Rl, R2, R3, R4 as necessary to quickly provide additional operating voltage or lesser operating voltage as needed.

[0047] In addition to providing specific colors at reduced power to street lighting systems and other loads 112 at predefined voltages (i.e., 120, 208, 240, 277 or 480 volts), the present apparatus and system can provide reduced power to obtain a target operational voltage at any voltage level.

[0048] While one or more embodiments of the present invention have been illustrated in detail, the skilled artisan will appreciate that modifications and adaptations to those embodiments can be made without departing from the scope of the present invention as set forth in the following claims.