INDUCTIVE POWER SUPPLY WITH DEVICE IDENTIFICATION

• US 20080157603A1
• Filed: 12/27/2007
• Published: 07/03/2008
• Est. Priority Date: 03/23/2006
• 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., Mollema, Scott A.
• Granted Patent: US 7,989,986 B2
• Time in Patent Office: Days
• US Class Current: 307/104
• CPC Class Codes: G01R 31/40 Testing power supplies testing photovoltaic devices H02S50/10
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H02J 7/00045 Authentication, i.e. circuits for checking compatibility between one component, e.g. a battery or a battery charger, and another component, e.g. a power source
• CPC Class Codes: H04B 5/0037 for power transfer
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer
• CPC Class Codes: Y02E 60/00 Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
• CPC Class Codes: Y04S 40/121 using the power network as support for the transmission
• CPC Class Codes: Y04S 40/126 using wireless data transmission

Abstract

An inductive power supply system to identify remote devices using unique identification frequencies. The system includes an AIPS and a tank circuit capable of inductively providing power to a remote device at different frequencies, and a sensor for sensing the reflected impedance of the remote device at tank circuit. The system further includes a plurality of different remote devices, each having a unique resonance frequency. In operation, the AIPS is capable of identifying the type of remote device present in the inductive field by applying power to a remote device at a plurality of unique identification frequencies until the remote device establishes resonance in response to one of the identification frequencies. The AIPS includes a controller that recognizes when resonance has been established by evaluating sensor data, which is representative of the reflected impedance of the remote device. Once the identity of a remote device is determined, the AIPS may pull operating parameters for the remove device from memory to ensure efficient operation and to assist in recognizing fault conditions.

Claims

1. A method for controlling an inductive power supply, comprising the steps of:

associating an identification frequency with a remote device, the identification frequency including at least one frequency at which the remote device has a resonant frequency;

applying an inductive field to a remote device at the identification frequency;

determining whether the remote device has a resonant frequency substantially at the applied identification frequency; and

operating the inductive power supply based on an outcome of said determining step.

2. The method of claim 1 wherein said operating step is further defined as the steps of:

retrieving at least one parameter for the remote device from a memory associated with the inductive power supply, if the remote device has a resonant frequency substantially at the applied identification frequency; and

after said retrieving step, operating the inductive power supply to apply power to the remote device in accordance with the parameter.

3. The method of claim 2 further including the step of storing in memory at least one parameter for the remote device associated with the identification frequency.

4. The method of claim 3 wherein said associating step is further defined as associating a plurality of different identification frequencies with a plurality of different remote devices;

and

wherein said applying step and said determining step are repeated for each of the different identification frequencies until the remote device is determined to have a resonant frequency substantially at the applied identification frequency.

5. The method of claim 4 wherein said storing step is further defined as storing in memory at least one parameter for each of the plurality of different remote devices.

6. The method of claim 5 further including the step of actively configuring each of the plurality of remote devices to include a resonant frequency at a desired unique frequency, the identification frequency including the resonant frequency, whereby each of said plurality of remote devices may be uniquely identified by its corresponding identification frequency.

7. The method of claim 5 further including the step of actively configuring each of the plurality of remote devices to include a plurality of resonant frequencies, the identification frequency associated with each of the remote devices including the plurality of resonant frequencies included in that remote device, whereby each remote device may be uniquely identified by the plurality of resonant frequencies.

8. The method of claim 6 wherein said step of actively configuring each of the plurality of remote devices includes the step of incorporating a capacitor into each of the plurality of remote devices to provide a resonant frequency corresponding to the capacitor value.

9. A method for operating an inductive power supply comprising the steps of:

storing a plurality of identification profiles and at least one operating parameter associated with each identification profile in a memory associated with an inductive power supply;

applying inductive power to a remote device at one or more frequencies to determine the identification profile of the remote device contained within the inductive field;

comparing the determined profile with the stored identification profiles to determine an identity of the remote device;

retrieving an operating parameter from the memory upon determination of the identity of the remote device; and

operating the inductive power supply in accordance with the retrieved operating parameter.

10. The method of claim 9 further including the step of determining an inherent resonant frequency profile of a remote device to determine the identification profile for the remote device.

11. The method of claim 9 further including the step of providing a remote device with an identification profile.

12. The method of claim 11 wherein said step of providing a remote device with an identification profile includes the step of incorporating an identification capacitor into the remote device.

13. The method of claim 11 wherein said step of providing a remote device with an identification profile includes the step of incorporating a plurality of identification capacitors into the remote device.

14. The method of claim 9 wherein each of the identification profiles includes one or more resonant frequencies.

15. The method of claim 14 wherein said applying step includes the steps of:

applying a pulse of power at the one or more frequencies associated with the stored profile; and

sensing current in the tank circuit to determine whether the remote device has a resonant frequency at the one or more applied frequencies.

16. A method for securely controlling an inductive power supply, comprising the steps of:

determining a common identification profile for remote devices to be powered by the inductive power supply, the common identification profile including one or more resonant frequencies;

providing each remote device to be powered by the inductive power supply with the common identification profile;

applying an inductive field to a remote device at the one or more resonant frequencies of the common identification profile;

determining whether said remote device has a resonant frequency profile corresponding with the common identification profile; and

operating the inductive power supply to power the remote device if the remote device has a resonant frequency profile corresponding with the common identification profile.

17. The method of claim 16 further including the steps of:

providing each remote device to be powered by the inductive power supply with a unique identification profile;

storing the plurality of unique identification profiles and an associated operating parameter in a memory associated with the inductive power supply;

once it is determined that the remote device has a resonant frequency profile corresponding with the common identification profile, applying an inductive field to the remote device at one or more resonant frequencies corresponding to one or more of the unique identification profiles;

determining whether said remote device has a resonant frequency profile corresponding with one of the unique identification profiles;

retrieving the associated operating parameter from the memory upon determining that the remote device corresponds with one of the unique identification profiles; and

following said retrieving step, operating the inductive power supply in accordance with the retrieved operating parameter to power the remote device.

18. An inductive power supply comprising:

inductive field generating circuitry;

frequency control circuitry electrically connected to said inductive field generating circuitry, said control circuitry capable of operating said inductive field generating circuitry at a plurality of different frequencies;

reflected impedance sensing circuitry to sense a characteristic of power in the inductive power supply, said characteristic being indicative of a reflected impedance of a remote device;

identification circuitry to determine an identification profile of a remote device as a function of output of said reflected impedance sensing circuitry; and

power supply control circuitry for supplying power to the remote device as a function of the identification profile of the remote device.

19. The inductive power supply of claim 18 wherein said inductive field generating circuitry includes a tank circuit having a primary.

20. The inductive power supply of claim 19 wherein said frequency control circuitry includes an oscillator and a driver.

21. The inductive power supply of claim 20 wherein said reflected impedance sensing circuitry includes a current sense transformer coupled to said tank circuit.

22. The inductive power supply of claim 21 wherein said identification circuitry includes a microcontroller and a memory, said memory storing a plurality of identification profiles for different remote devices and a plurality of operating parameters, each of said operating parameters associated with one or more of the plurality of identification profiles.

23. An inductive power supply and remote device combination comprising:

a remote device having an identification profile, said identification profile including one or more resonant frequencies; and

an inductive power supply having;

a driver;

a tank circuit having a primary;

a sensor in said tank circuit adapted to sense a characteristic of power in said tank circuit indicative of a reflected impedance of said remote device;

identification circuitry to determine said identification profile of said remote device as a function of output of said sensor; and

control circuitry for controlling operation of said inductive power supply as a function of said identification profile of said remote device.

24. The combination of claim 23 wherein said inductive power supply includes a memory storing at least one identification profile and at least one operating parameter associated with said identification profile.

25. The combination of claim 23 wherein said remote device includes an identification capacitor.

26. The combination of claim 23 wherein said identification profile includes an inherent resonant frequency of said remote device.