US-12627169-B2 - Bidirectional power transfer system, method of operating the same, and wireless power system

Abstract

The system includes a power stage for inverting an inputted power signal and for rectifying a received power signal. The system includes a trigger circuit for synchronizing wireless power transfer; a clock generator for generating a clock signal; a switching element electrically connected to the power stage, and selectively electrically connected to the trigger circuit and the clock generator, such that when the switching element electrically connects the clock generator to the power stage, a transceiver element is configured to transfer power by generating an electric field and/or a magnetic field, and when the switching element electrically connects the trigger circuit to the power stage, the transceiver element is configured to extract power from a generated electric field and/or a generated magnetic field.

Inventors

• Amir TAHAVORGAR

Assignees

• SOLACE POWER INC.

Dates

Publication Date

20260512

Application Date

20240514

Claims (19)

1. 1 . A bidirectional wireless power transfer system for transferring power, the system comprising a controller operable to: connect a clock generator configured to generate a clock signal to a power stage, the power stage configured to invert an inputted power signal for generating an electric field and/or a magnetic field by a transceiver element, or connect a trigger circuit configured to synchronize wireless power transfer to the power stage, the power stage configured to rectify a received power signal extracted from an electric field and/or a magnetic field generated by the transceiver element.
2. 2 . The system of claim 1 , further comprising: the transceiver element for transferring power by generating an electric field and/or a magnetic field, and for extracting power from a generated electric field and/or a generated magnetic field; the power stage electrically connected to the transceiver element, the power stage for inverting the inputted power signal and for rectifying the received power signal; the trigger circuit for synchronizing wireless power transfer; the clock generator for generating the clock signal; and a switching element electrically connected to the power stage, wherein the controller is operable to selectively electrically connect the switching element to the trigger circuit and the clock generator, such that, when the switching element electrically connects the clock generator to the power stage, the transceiver element is configured to transfer power by generating an electric field and/or a magnetic field, and when the switching element electrically connects the trigger circuit to the power stage, the transceiver element is configured to extract power from a generated electric field and/or a generated magnetic field.
3. 3 . The system of claim 2 , wherein the clock generator generates the clock signal to control the power stage.
4. 4 . The system of claim 2 , wherein the power stage comprises an amplifier.
5. 5 . The system of claim 4 , wherein the amplifier is a class E power amplifier.
6. 6 . The system of claim 2 , wherein the power stage comprises an input stage.
7. 7 . The system of claim 6 , wherein the input stage comprises a matching network.
8. 8 . The system of claim 7 , wherein the matching network comprises a single impedance inverter or a double impedance inverter.
9. 9 . The system of claim 2 , wherein the power stage comprises a gate driver for controlling the power stage.
10. 10 . The system of claim 2 , wherein the clock generator comprises an oscillator.
11. 11 . The system of claim 2 , wherein the trigger circuit is for controlling operation of the power stage to synchronize a power signal received by the transceiver element.
12. 12 . The system of claim 2 , wherein the trigger circuit comprises a sampling circuit for sampling current or voltage.
13. 13 . The system of claim 12 , wherein the current being sampled is load independent.
14. 14 . The system of claim 12 , wherein the voltage being sampled is load independent.
15. 15 . The system of claim 2 , further comprising a converter for converting a voltage of the inputted power signal or the received power signal.
16. 16 . The system of claim 15 , wherein the converter is a bidirectional buck-boost converter.
17. 17 . A method of operating a bidirectional wireless power transfer system, the system comprising: a transceiver element for transferring power by generating an electric field and/or a magnetic field, and for extracting power from a generated electric field and/or a generated magnetic field; a power stage electrically connected to the transceiver element, the power stage for inverting an inputted power signal and for rectifying a received power signal; a trigger circuit for synchronizing wireless power transfer; a clock generator for generating a clock signal; a switching element electrically connected to the power stage, and selectively electrically connected to the trigger circuit and the clock generator, such that: when the switching element electrically connects the clock generator to the power stage, the transceiver element is configured to transfer power by generating an electric field and/or a magnetic field, and when the switching element electrically connects the trigger circuit to the power stage, the transceiver element is configured to extract power from a generated electric field and/or a generated magnetic field; and a controller operable to connect the clock generator to the power stage, or the trigger circuit to the power stage, the method comprising: controlling the switching element via the controller to connect the power stage to the trigger circuit to extract power, or controlling the switching element via the controller to connect the power stage to the clock generator to transfer power.
18. 18 . The method of claim 17 , wherein the controlling the switching element comprises operating the switching element.
19. 19 . The method of claim 17 , further comprising controlling the switching element via the controller to disconnect the power stage from the clock generator, or disconnecting the power stage from the trigger circuit, wherein disconnecting the power stage from the trigger circuit or the clock generator comprises operating the switching element.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application is a continuation of and claims priority under 35 U.S.C. §§ 120/121 to U.S. patent application Ser. No. 17/899,711 filed on Aug. 31, 2022, which claims the benefit of U.S. Provisional Application No. 63/238,829 filed on Aug. 31, 2021, the entire contents of each of which are hereby incorporated by reference. FIELD The subject disclosure relates generally to wireless power transfer, and in particular to bidirectional wireless power transfer systems for transferring power, methods of operating the same, and wireless power systems. BACKGROUND Wireless power transfer systems such as wireless chargers are becoming an increasingly important technology to enable the next generation of devices. The potential benefits and advantages offered by the technology is evident by the increasing number of manufacturers and companies investing in the technology. A variety of wireless power transfer systems are known. A typical wireless power transfer system includes a power source electrically connected to a wireless power transmitter, and a wireless power receiver electrically connected to a load. In magnetic induction systems, the transmitter has a transmitter coil with a certain inductance that transfers electrical energy from the power source to the receiver, which has a receiver coil with a certain inductance. Power transfer occurs due to coupling of magnetic fields between the coils or inductors of the transmitter and receiver. The range of these magnetic induction systems is limited, and the coils or inductors of the transmitter and receiver must be tightly coupled, i.e. have a coupling factor above 0.5 and be in optimal alignment for efficient power transfer. There also exist resonant magnetic systems in which power is transferred due to coupling of magnetic fields between the coils or inductors of the transmitter and receiver. The transmitter and receiver inductors may be loosely coupled, i.e. have a coupling factor below 0.5. However, in resonant magnetic systems the inductors are resonated using at least one capacitor. Furthermore, in resonant magnetic systems, the transmitter is self-resonant and the receiver is self-resonant. The range of power transfer in resonant magnetic systems is increased over that of magnetic induction systems and alignment issues are rectified. While electromagnetic energy is produced in magnetic induction and resonant magnetic systems, the majority of power transfer occurs via the magnetic field. Little, if any, power is transferred via electric induction or resonant electric induction. In electrical induction systems, the transmitter and receiver have capacitive electrodes. Power transfer occurs due to coupling of electric fields between the capacitive electrodes of the transmitter and receiver. Similar, to resonant magnetic systems, there exist resonant electric systems in which the capacitive electrodes of the transmitter and receiver are made resonant using at least one inductor. The inductor may be a coil. In resonant electric systems, the transmitter is self-resonant and the receiver is self-resonant. Resonant electric systems have an increased range of power transfer compared to that of electric induction systems and alignment issues are rectified. While electromagnetic energy is produced in electric induction and resonant electric systems, the majority of power transfer occurs via the electric field. Little, if any, power is transferred via magnetic induction or resonant magnetic induction. While some wireless power transfer systems are known, improvements are desired. It is therefore an object to provide a novel wireless power transfer transmitter, receiver, system and method of wirelessly transferring power. This background serves only to set a scene to allow a person skilled in the art to better appreciate the following brief and detailed descriptions. Therefore, none of the above discussion should necessarily be taken as an acknowledgement that the discussion is part of the state of the art or is common general knowledge. BRIEF DESCRIPTION Accordingly, in one aspect there is provided a bidirectional wireless power transfer system for transferring power. The system may provide for wireless power transfer in a forward power flow direction, and in opposite reverse power flow direction, which is opposite the forward power flow direction. The system may comprise: a power stage electrically connected to a transceiver element for transferring power by generating an electric field and/or a magnetic field, and for extracting power from a generated electric field and/or a generated magnetic field, the power stage for inverting an inputted power signal and for rectifying a received power signal; a trigger circuit for synchronizing wireless power transfer; a clock generator for generating a clock signal; and a switching element electrically connected to the power stage, and selectively electrically connected to the trigger circuit a