EFFICIENCY MONITOR FOR INDUCTIVE POWER TRANSMISSION

• US 20140312688A1
• Filed: 07/03/2014
• Published: 10/23/2014
• Est. Priority Date: 03/22/2007
• Status: Active Grant

• Current Assignee: Powermat Technologies, Ltd.
• Original Assignee: Powermat Technologies, Ltd.
• Inventors: AZANCOT, Yossi, GREENWALD, Oola, BEN-SHALOM, Amir, ROFE, Arik
• Granted Patent: US 9,362,049 B2
• Time in Patent Office: Days
• US Class Current: 307/11
• CPC Class Codes: G01V 3/08 operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices with electromagnetic waves G01V3/12
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves
• CPC Class Codes: H02J 50/402 the two or more transmitting or the two or more receiving devices being integrated in the same unit, e.g. power mats with several coils or antennas with several sub-antennas
• CPC Class Codes: H02J 50/70 involving the reduction of electric, magnetic or electromagnetic leakage fields
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• 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: H02J 7/00309 Overheat or overtemperature protection
• CPC Class Codes: H02J 7/00712 the cycle being controlled or terminated in response to electric parameters
• CPC Class Codes: H02J 7/007192 in response to temperature
• CPC Class Codes: H02M 1/0058 by employing soft switching techniques, i.e. commutation of transistors when applied voltage is zero or when current flow is zero using an auxiliary actively switched resonant commutation circuit connected to an intermediate DC voltage or between two push-pull branches of an inverter bridge H02M7/4811; in resonant inverters H02M7/4815; in inverters operating from a resonant DC source H02M7/4826
• CPC Class Codes: H02M 3/3376 with automatic control of output voltage or current
• 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

Abstract

An inductive power receiver configured for receiving power transferred from an inductive power outlet having a primary coil includes a secondary coil configured to form an inductive couple with the primary coil thereby facilitating the power transfer. The inductive power receiver further includes a transmission circuit having a variable amplifier configured to vary the voltage of the power drawn by the secondary coil, and a modulator configured to control the variable amplifier. The inductive power receiver is configured to modulate a signal by the varying of the voltage. An inductive power outlet configured for transferring power to the inductive power receiver includes a primary coil and a receiving circuit configured to detect changes in voltage of the power transferred and to produce an output signal based on the changes.

Claims

1. A method for receiving power from an inductive power outlet, the method comprising:

providing an inductive power receiver configured for the receiving of power, said inductive power receiver comprising;

a coil configured to draw power from said inductive power outlet;

a principal electrical load configured to receive power drawn by said coil; and

an ancillary electrical load configured to be selectively connected to said coil to receive power drawn thereby;

modulating a bit-rate signal with an input signal to produce a modulated signal; and

intermittently connecting said ancillary load to said coil according to the modulated signal, thereby transmitting a modulated signal from said inductive power receiver to said inductive power outlet while receiving power therefrom.

2. The method according to claim 1, wherein said ancillary load is much smaller than said principal load.

3. The method according to claim 1, wherein said input signal carries encoded data pertaining to one or more selected from the group including the presence of said principal electric load, a required operating voltage for said principal electric load, a required operating current for said principal electric load, a required operating temperature for said principal electric load, a measured operating voltage for said principal electric load, a measured operating current for said principal electric load, a measured operating temperature for said principal electric load, and a user identification code.

4. The method according to claim 1, wherein said input signal provides data relating to parameters of the principal load.

5. The method according to claim 4, wherein said parameters include one or more selected from the group including required operating voltage, required operating current, required operating temperature, operating voltage measured during operation of the principal load, operating current measured during operation of the principal load, and operating temperature measured during operation of the principal load.

6. The method according to claim 1, wherein said input signal provides supplementary data unrelated to control of power transmission.

7. The method according to claim 1, wherein said inductive power receiver further comprises a switching unit configured to facilitate the connecting.

8. The method according to claim 7, wherein said switching unit is configured to receive said bit-rate signal and an input signal.

9. The method according to claim 7, wherein said switching unit comprises a frequency divider configured to provide said bit-rate signal, a microcontroller configured to modulate the bit-rate signal according the input signal, and a switch.

10. The method according to claim 1, wherein said inductive power receiver further comprises a modulator configured for the modulating.

11. A method for transferring power to an inductive power receiver, the method comprising:

providing an inductive power outlet comprising;

a coil configured for the transferring;

a current monitor configured to monitor power transferred by said coil and producing a current signal based thereupon; and

a correlator configured to cross-correlate said current signal with a bit-rate signal, thereby producing an output signal;

transferring power to said inductive power receiver via said coil;

monitoring a current transferred, thereby producing a primary current signal; and

cross-correlating the primary current signal with said bit-rate signal to generate an output signal, thereby receiving a signal from said inductive power receiver while transferring power thereto.

12. The method according to claim 11, further comprising regulating the transferred power based on said output signal.

13. The method according to claim 11, wherein said inductive power outlet further comprises a frequency divider configured to provide said bit-rate signal.

14. The method according to claim 11, wherein said inductive power outlet further comprises a microcontroller configured to pass a control signal based on said output signal.

15. The method according to claim 14, wherein said control signal provides one or more instructions to a control a power source of the inductive power outlet so as to regulate the power transferred.

16. The method according to claim 14, wherein said control signal provides supplementary data unrelated to control of power transmission.

17. A method for transferring power comprising:

providing an inductive power outlet comprising;

a primary coil configured for the transferring; and

a current monitor configured to monitor power transferred by said primary coil and producing a current signal based thereupon;

providing an inductive power receiver configured for the receiving of power, said inductive power receiver comprising;

a secondary coil configured to draw power from said primary coil;

a principal electrical load configured to receive power drawn by said secondary coil; and

an ancillary electrical load configured to be selectively connected to said secondary coil to receive power drawn thereby;

inductively coupling said primary and secondary coils;

transferring power from said inductive power outlet to said inductive power receiver via said coupled coils;

said inductive power receiver producing a modulated signal;

intermittently connecting said ancillary load to said secondary coil according to the modulated signal, thereby transmitting a modulated signal from said inductive power receiver to said inductive power outlet while receiving power therefrom;

monitoring, by said inductive power outlet, current transferred by the primary coil, thereby producing a primary current signal; and

said inductive power outlet generating an output signal, thereby receiving a signal from said inductive power receiver while transferring power thereto.

18. The method according to claim 17, wherein said inductive power receiver further comprises a microcontroller and the step of producing a modulated signal comprises modulating a bit-rate signal according an input signal.

19. The method according to claim 17, wherein said inductive power outlet further comprises a microcontroller configured to pass a control signal based on said output signal.

20. The method according to claim 19 wherein the step of generating an output signal comprises cross-correlating a primary current signal with a bit-rate signal.