Devices, systems, and method for power control of dynamic electric vehicle charging systems
View Patent ↗Systems, methods, and apparatus are disclosed for wirelessly charging an electric vehicle. In one aspect, a method of wirelessly charging an electric vehicle is provided. The method includes, obtaining a request from the electric vehicle for a level of charging power to be delivered from a power transmitter to the electric vehicle via a charging field. The method further includes controlling a current or voltage of the power transmitter based on a power efficiency factor and the requested level of charging power.
1. An apparatus for wirelessly charging an electric vehicle, comprising:
a communication receiver configured to obtain a request for a level of charging power, wherein the request indicates a level of charging power to be delivered from a power antenna circuit to the electric vehicle via a charging field; and
a controller operationally coupled to the communication receiver and configured to control a current or voltage generator of the power antenna circuit based on a power efficiency factor and the requested level of charging power, wherein the power efficiency factor during a first time period is determined without receiving an amount of power measurement at the electric vehicle during the first time period.
2. The apparatus of claim 1 , wherein the power efficiency factor is based at least in part on a pre-programmed value retrievable by the controller.
3. The apparatus of claim 2 , wherein the pre-programmed value comprises a value of a lookup table comprising different pre-programmed values for different charging power levels.
4. The apparatus of claim 1 , wherein the power efficiency factor comprises a determination of an efficiency of at least the power delivered by the power antenna circuit to a receive antenna and a rectifier circuit of the electric vehicle.
5. The apparatus of claim 1 , further comprising a sensor configured to measure a current or voltage of the power antenna circuit.
6. The apparatus of claim 5 , wherein the controller is further configured to adjust the power efficiency factor based on the measured current or voltage of the power antenna circuit.
7. The apparatus of claim 1 , wherein the communication receiver is further configured to receive an output power measurement or an output error value from the electric vehicle.
8. The apparatus of claim 7 , wherein the controller is further configured to adjust the power efficiency factor based on the output power measurement or the output error value.
9. The apparatus of claim 7 , wherein the controller is further configured to control the current or voltage generator based on the power efficiency factor during a first time period, and wherein the output power measurement is received after the first time period.
10. The apparatus of claim 7 , wherein the output error value comprises a difference between the output power measurement of the electric vehicle and the requested level of charging power, and wherein the output power measurement comprises a measurement of a level of charging power delivered to a load of the electric vehicle from the power antenna circuit.
11. The apparatus of claim 7 , wherein the controller is further configured to control the current or voltage generator of the power antenna circuit based on a ratio of an input power of the power antenna circuit and the output power measurement.
12. The apparatus of claim 11 , wherein an initial value of the ratio comprises a pre-programmed value retrievable by the controller.
13. The apparatus of claim 11 , wherein the controller is further configured to adjust the ratio based on the output power measurement or the output error value.
14. The apparatus of claim 1 , wherein the controller is further configured to control the current or voltage generator of the power antenna circuit based on a change in an electrical characteristic of the power antenna circuit or a receive circuit of the electric vehicle.
15. The apparatus of claim 14 , wherein the electrical characteristic comprises at least one of a current, or an impedance, or a voltage, or a resistance, or a inductance, or resonant frequency, or a phase, or any combination thereof.
16. A method for wirelessly charging an electric vehicle, comprising:
obtaining a request from the electric vehicle for a level of charging power, wherein the request indicates a level of charging power to be delivered from a power transmitter to the electric vehicle via a charging field; and
controlling a current or voltage of the power transmitter based on a power efficiency factor and the requested level of charging power, wherein the power efficiency factor during a first time period is determined without receiving an amount of power measurement at the electric vehicle during the first time period.
17. The method of claim 16 , wherein the power efficiency factor is based at least in part on a pre-programmed value retrievable by the controller.
18. The method of claim 16 , wherein the power efficiency factor comprises a determination of an efficiency of at least the power delivered by the power antenna circuit to a receive antenna and a rectifier circuit of the electric vehicle.
19. The method of claim 16 , further comprising adjusting the power efficiency factor based on a measured current or voltage of the power transmitter.
20. The method of claim 16 , further comprising receiving an output power measurement or an output error value from the electric vehicle.
21. The method of claim 20 , further comprising adjusting the power efficiency factor based on the output power measurement or the output error value.
22. The method of claim 20 , wherein controlling a current or voltage of the power transmitter comprises controlling a current or voltage of the power transmitter based on a ratio of an input power of the power antenna circuit and the output power measurement.
23. The method of claim 22 , wherein controlling a current or voltage of the power transmitter comprises controlling a current or voltage of the power transmitter based on the output power measurement or the output error value.
24. The method of claim 16 , wherein controlling a current or voltage of the power transmitter comprises controlling a current or voltage of the power transmitter based on a change in an electrical characteristic of the power transmitter or the electric vehicle.
25. The method of claim 24 , wherein the electrical characteristic comprises at least one of a current, or an impedance, or a voltage, or a resistance, or a inductance, or resonant frequency, or a phase, or any combination thereof.
26. An apparatus for wirelessly charging an electric vehicle, comprising:
means for obtaining a request from the electric vehicle for a level of charging power, wherein the request indicates a level of charging power to be delivered from a power antenna circuit to the electric vehicle via a charging field; and
means for controlling a current or a voltage of the power antenna circuit based on a power efficiency factor and the requested level of charging power, wherein the power efficiency factor during a first time period is determined without receiving an amount of power measurement at the electric vehicle during the first time period.
27. The apparatus of claim 26 , wherein the obtaining means comprises a receiver, wherein the controlling means comprises a controller.
28. The apparatus of claim 26 , further comprising adjusting the power efficiency factor based on a measured current or voltage of the power antenna circuit.
29. The apparatus of claim 26 , further comprising:
means for receiving an output power measurement or an output error value from the electric vehicle; and
means for adjusting the power efficiency factor based on the output power measurement or the output error value.