ADAPTIVE INDUCTIVE POWER SUPPLY

• US 20100103702A1
• Filed: 11/10/2009
• Published: 04/29/2010
• Est. Priority Date: 06/21/1999
• Status: Active Grant

• Current Assignee: Philips IP Ventures B.V. (Koninklijke Philips N.V.)
• Original Assignee: Access Business Group International LLC (Alticor Incorporated)
• Inventors: Baarman, David W.
• Granted Patent: US 9,036,371 B2
• Time in Patent Office: Days
• US Class Current: 363/16
• CPC Class Codes: A61L 2/10 Ultraviolet radiation
• CPC Class Codes: H02J 13/00022 using wireless data transmission
• CPC Class Codes: H02J 13/00024 by means of mobile telephony
• CPC Class Codes: H02J 13/00028 involving the use of Internet protocols
• CPC Class Codes: H02J 2310/22 The load being a portable electronic device
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02M 3/015 with means for adaptation of resonance frequency, e.g. by modification of capacitance or inductance of resonance circuit
• CPC Class Codes: H02M 3/33523 with galvanic isolation between input and output of both the power stage and the feedback loop
• CPC Class Codes: H02M 3/33571 Half-bridge at primary side of an isolation transformer
• CPC Class Codes: H02M 3/33576 having at least one active switching element at the secondary side of an isolation transformer
• CPC Class Codes: H02M 7/4815 Resonant converters H02M7/4811 and H02M7/4826 take precedence
• CPC Class Codes: H02M 7/4818 with means for adaptation of resonance frequency, e.g. by modification of capacitance or inductance of resonance circuits
• CPC Class Codes: H02M 7/53803 with automatic control of output voltage or current
• CPC Class Codes: H05B 41/36 Controlling
• CPC Class Codes: H05B 47/20 Responsive to malfunctions or to light source life; for protection
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y04S 20/246 the system involving the remote operation of lamps or lighting equipment

Abstract

A contactless power supply has a dynamically configurable tank circuit powered by an inverter. The contactless power supply is inductively coupled to one or more loads. The inverter is connected to a DC power source. When loads are added or removed from the system, the contactless power supply is capable of modifying the resonant frequency of the tank circuit, the inverter frequency, the inverter duty cycle or the rail voltage of the DC power source.

Claims

7. A contactless power supply system comprising:

an inductive power supply having at least one operating parameter, said inductive power supply having a resonant frequency, an operating frequency, a rail voltage and a duty cycle;

a remote device capable of inductively receiving power from said power supply via an inductive coupling when placed within sufficient proximity to said inductive power supply, said remote device capable of affecting said operating parameters when placed within sufficient proximity to said inductive power supply; and

wherein said power supply includes;

a tank circuit having a primary for inductively transferring power to said remote device; and

a controller continually monitoring said operating parameter of said power supply, said controller reconfiguring the power supply when said operating parameters fall outside a nominal range, said controller programmed to reconfigure the power supply by adjusting at least two of said resonant frequency, said operating frequency, said rail voltage and said duty cycle.

1. A contactless power supply for supplying power wirelessly to a remote device comprising:

a tank circuit having a primary for transferring power to the remote device by an inductive coupling, said tank circuit having a resonant frequency;

circuitry for applying power at a rail voltage to said tank circuit, said circuitry applying said power at an operating frequency and a duty cycle; and

a controller coupled to said circuitry, said controller configured to vary at least two of said resonant frequency of said tank circuit, said operating frequency of said power, said duty cycle of said power and said rail voltage of said power.

2. The contactless power supply of claim 1 wherein said controller is configured to vary at least three of said resonant frequency of said tank circuit, said operating frequency of said power, said duty cycle of said power and said rail voltage of said power.

3. The contactless power supply of claim 1 wherein said controller is configured to vary said resonant frequency of said tank circuit, said operating frequency of said power, said duty cycle of said power and said rail voltage of said power.

4. The contactless power supply of claim 1 wherein said at least two of said resonant frequency of said tank circuit, said operating frequency of said power, said duty cycle of said power and said rail voltage of said power is further defined as said operating frequency of said power and said rail voltage of said power.

5. The contactless power supply of claim 1 wherein said at least two of said resonant frequency of said tank circuit, said operating frequency of said power, said duty cycle of said power and said rail voltage of said power is further defined as said operating frequency of said power and said duty cycle of said power.

6. The contactless power supply of claim 1 further including a circuit sensor coupled to said tank circuit and to said controller, said circuit sensor providing said controller with an input indicative of a characteristic of power in said tank circuit;

and

wherein said controller is configured to vary at least two of said resonant frequency of said tank circuit, said operating frequency of said power, said duty cycle of said power and said rail voltage of said power as a function of said input indicative of a characteristic of power in said resonant circuit.

8. The contactless power supply system of claim 7 further including a circuit sensor coupled to said resonant circuit and to said controller, said circuit sensor providing said controller with an input indicative of a characteristic of power in said resonant circuit;

and

wherein said controller is configured to vary at least two of a rail voltage of a resonant frequency of the power supply, an operating frequency of the power supply, a duty cycle of the power supply and a rail voltage of the power supply as a function of said input indicative of a characteristic of power in said resonant circuit.

9. The contactless power supply system of claim 7 wherein said controller is configured to vary said resonant frequency, said operating frequency, said rail voltage and said duty cycle.

10. The contactless power supply system of claim 7 wherein said at least two of said resonant frequency, said operating frequency, said duty cycle and said rail voltage is further defined as said operating frequency and said rail voltage.

11. The contactless power supply system of claim 7 wherein said at least two of said resonant frequency, said operating frequency, said duty cycle and said rail voltage is further defined as said operating frequency and said duty cycle.

12. The contactless power supply system of claim 7 further including a circuit sensor coupled to said controller, said circuit sensor providing said controller with an input indicative of a characteristic of power in the power supply;

and

wherein said controller is configured to vary at least two of said resonant frequency, said operating frequency, said duty cycle and said rail voltage as a function of said input.

13. The contactless power supply system of claim 7 wherein said circuit sensor is a current sensor.

8-1. The contactless power supply system of claim 7 wherein said controller is configured to vary at least three of a rail voltage of said resonant frequency, said operating frequency, said duty cycle and said rail voltage.

14. A method of operating an inductive power supply for a remote device, the method including the steps of:

applying power to a tank circuit within the inductive power supply;

establishing an inductive coupling between the inductive power supply to the remote device;

monitoring at least one operating parameter of the inductive power supply after establishing the inductive coupling;

based upon said monitoring step, reconfiguring the inductive power supply by;

adjusting a first characteristic of the power supply, the first characteristic being one of a resonant frequency of a tank circuit, an operating frequency of the power applied to the tank circuit, a rail voltage of the power applied to the tank circuit, or a duty cycle of the power applied to the tank circuit; and

adjusting a second characteristic of the power supply, the second characteristic being one of a resonant frequency of the tank circuit, an operating frequency of the power applied to the tank circuit, a rail voltage of the power applied to the tank circuit, or a duty cycle of the power applied to the tank circuit and being different from the first characteristic.

15. The method of claim 14 wherein said monitoring step is further defined as sensing a characteristic of power in the power supply.

16. The method of claim 15 wherein said sensing step is further defined as sensing current in the tank circuit.

17. The method of claim 14 wherein said adjusting a first characteristic is further defined as adjusting an operating frequency of the power applied to the power supply.

18. The method of claim 17 wherein said adjusting a second characteristic is further defined as adjusting at least one of the rail voltage of the power applied to the tank circuit and the duty cycle of the power applied to the tank circuit.

19. The method of claim 14 wherein said adjusting a first characteristic is further defined as repeatedly adjusting the first characteristic until the first characteristic is at a best known setting.

20. The method of claim 19 wherein said adjusting a second characteristic is further defined as repeatedly adjusting the second characteristic until the second characteristic is at a best known setting.

21. The method of claim 14 wherein said step of reconfiguring the inductive power supply further includes:

adjusting a third characteristic of the power supply, the third characteristic being one of a resonant frequency of a tank circuit, an operating frequency of the power applied to the tank circuit, a rail voltage of the power applied to the tank circuit, or a duty cycle of the power applied to the tank circuit and being different from the first characteristic and the second characteristic.

22. The method of claim 21 wherein said step of reconfiguring the inductive power supply further includes:

adjusting a fourth characteristic of the power supply, the fourth characteristic being one of a resonant frequency of a tank circuit, an operating frequency of the power applied to the tank circuit, a rail voltage of the power applied to the tank circuit, or a duty cycle of the power applied to the tank circuit and being different from the first characteristic, the second characteristic and the third characteristic.

23. A method for controlling operation of an inductive power supply system, comprising the steps of:

establishing an inductive coupling between an inductive power supply and a remote device, the inductive power supply having a controller and a tank circuit;

adjusting a resonant frequency of the inductive power supply when the remote device is inductively coupled with the inductive power supply, said adjusting a resonant frequency including adjusting with the controller at least one of a variable capacitance or a variable inductance of the tank circuit;

adjusting at least one of an operating frequency of the inductive power supply, a duty cycle of the inductive power supply and a rail voltage of the inductive power supply, wherein adjusting the operating frequency of the inductive power supply and adjusting the duty cycle of the inductive power supply each include adjusting a drive circuit with the controller; and

repeating said step of adjusting at least one of an operating frequency of the inductive power supply, a duty cycle of the inductive power supply and a rail voltage of the inductive power supply during operation of the inductive power supply.

24. An inductive power supply for supplying power to a remote device that can be selectively placed in proximity to the inductive power supply to wirelessly receive power from the inductive power supply comprising:

a tank circuit having a primary for wirelessly transferring power to the remote device by an inductive coupling, said tank circuit having a resonant frequency;

an inverter for applying power to said tank circuit, said inverter applying power to said tank circuit at an operating frequency and a duty cycle;

a DC power source coupled to said inverter to supply DC power to said inverter, said DC power source having a rail voltage;

a drive circuit coupled to said inverter, said drive circuit dictating said operating frequency and said duty cycle; and

a controller for dynamically reconfiguring the inductive power supply, said controller configured to vary one of said resonant frequency of said tank circuit, said operating frequency of said inverter, said duty cycle of said inverter and said rail voltage of said DC power source, said controller configured to vary a second of said resonant frequency of said tank circuit, said operating frequency of said inverter, said duty cycle of said inverter and said rail voltage of said DC power source.

25. The inductive power supply of claim 24 wherein said controller is configured to monitor at least one operational characteristic of the inductive power supply to determine if the inductive power supply is operating effectively, said controller configured to reconfigure the inductive power supply upon a determination that the inductive power supply is not operating effectively.

26. The inductive power supply of claim 24 wherein said controller is configured to monitor at least one operational characteristic of the inductive power supply to determine if the inductive power supply is operating efficiently, said controller configured to reconfigure the inductive power supply upon a determination that the inductive power supply is not operating efficiently.

27. The inductive power supply of claim 24 wherein said controller is configured to search for the most efficient inductive power supply configuration to deliver power to the remote device by repeatedly reconfiguring the inductive power supply by repeatedly varying one of said resonant frequency of said tank circuit, said operating frequency of said inverter, said duty cycle of said inverter and said rail voltage of said DC power source.