WIRELESS POWER TRANSMISSION IN ELECTRIC VEHICLES
Exemplary embodiments are directed to bidirectional wireless power transfer using magnetic resonance in a coupling mode region between a charging base (CB) and a battery electric vehicle (BEV). For different configurations, the wireless power transfer can occur from the CB to the BEV and from the BEV to the CB.
1 . A system for wireless power transfer, comprising:
a first power converter circuit arranged in a full bridge topology comprising four active switching elements and configured to convert a power input signal to a first alternating current (AC) power output signal at an operating frequency;
a first wireless power circuit comprising a first inductive element electrically connected to a first capacitive element in series, the first inductive element configured to generate a first magnetic field in a region of wireless power transfer at the operating frequency based on the first AC power output signal;
a second capacitive element electrically connected in parallel to the first wireless power circuit;
a second inductive element electrically connected in series between the first power converter circuit the first wireless power circuit;
a second wireless power circuit comprising a third inductive element electrically connected in series with a third capacitive element, the third inductive element configured to generate a first received AC power signal at the operating frequency from the first magnetic field while in the region of wireless power transfer;
a fourth capacitive element electrically connected in parallel to the second wireless power circuit; and
a fourth inductive element electrically connected in series between the second wireless power circuit and a second power converter circuit,
the second power converter circuit arranged in a full bridge topology comprising four active switching elements and configured to convert the first received AC power signal to a first direct current (DC) power output signal.
2 . The system of claim 1 , wherein the second power converter operates as a synchronous rectifier.
3 . The system of claim 1 , wherein the system is configured as a bidirectional wireless power transfer system.
4 . The system of claim 3 , wherein the first power converter circuit is configured as a bidirectional power converter to convert the power input signal to the first AC power output signal at the operating frequency when operating in a transmit mode, and to convert a second received AC power signal received via the first wireless power circuit at the operating frequency to a second DC power output signal when operating in a receive mode.
5 . The system of claim 3 , wherein the first wireless power circuit is configured to generate the first magnetic field in a region of wireless power transfer at the operating frequency based on the first AC power output signal generated by the first power converter circuit when operating in a transmit mode, and to generate a second received AC power signal at the operating frequency from a second magnetic field generated by the second wireless power circuit while in the region of wireless power transfer when operating in a receive mode.
6 . The system of claim 3 , wherein the second wireless power circuit is configured to generate the first received AC power signal at the operating frequency from the first magnetic field generated by the first wireless power circuit while in the region of wireless power transfer when operating in a receive mode, and to generate a second magnetic field in the region of wireless power transfer at the operating frequency based on a second AC power output signal generated by the second power converter circuit when operating in a transmit mode.
7 . The system of claim 3 , wherein the second power converter circuit is configured as a bidirectional power converter to convert the first received AC power signal at the operating frequency to the first DC power output signal when operating in a receive mode, and to convert a DC power input signal to a second AC power output signal at the operating frequency when operating in a transmit mode.
8 . The system of claim 1 , wherein the second inductive element comprises a first inductor electrically connected to a first terminal of the first power converter and a second inductor electrically connected to a second terminal of the first power converter.
9 . The system of claim 1 , wherein the fourth inductive element comprises a first inductor electrically connected to a first terminal of the second power converter and a second inductor electrically connected to a second terminal of the second power converter.
10 . The system of claim 1 , wherein the system is configured to adapt to a load presented to the second power converter by adjusting at least one of a duty cycle of a pulse width modulation switching waveform of the first and second power converter and the operating frequency.
11 . The system of claim 1 , wherein the system is configured to control a level of power delivered to a load presented to the second power converter by adjusting at least one of a duty cycle of a pulse width modulation switching waveform of the first and second power converter and the operating frequency.
12 . The system of claim 1 , wherein the system is configured to maintain a power transfer efficiency of the system by adjusting at least one of a duty cycle of a pulse width modulation switching waveform of the first and second power converter and the operating frequency.
13 . A method for wirelessly transferring power, comprising:
at a first power converter circuit arranged in a full bridge topology comprising four active switching elements, converting a power input signal to a first alternating current (AC) power output signal at an operating frequency;
at a first wireless power circuit comprising a first inductive element electrically connected to a first capacitive element in series, generating a first magnetic field in a region of wireless power transfer at the operating frequency based on the first AC power output signal,
the first wireless power circuit being electrically connected in parallel to a second capacitive element, with a second inductive element being electrically connected in series between the first wireless power circuit and the first power converter circuit;
at a second wireless power circuit comprising a third inductive element electrically connected in series with a third capacitive element, the third inductive element generating a first received AC power signal at the operating frequency from the first magnetic field while in the region of wireless power transfer,
the second wireless power circuit being electrically connected in parallel to a fourth capacitive element, with a fourth inductive element being electrically connected in series between the second wireless power circuit and a second power converter circuit;
at the second power converter circuit converting the first received AC power signal to a first direct current (DC) power output signal, the second power converter circuit being arranged in a full bridge topology comprising four active switching elements.
14 . The method of claim 13 , wherein the second power converter operates as a synchronous rectifier.
15 . The method of claim 13 , further comprising operating as a bidirectional wireless power transfer system.
16 . The method of claim 16 , wherein the first power converter circuit, operating as a bidirectional power converter, converts the power input signal to the first AC power output signal at the operating frequency in a transmit mode, and converts a second received AC power signal received via the first wireless power circuit at the operating frequency to a second DC power output signal in a receive mode.
17 . The method of claim 16 , wherein the first wireless power circuit generates the first magnetic field in a region of wireless power transfer at the operating frequency based on the first AC power output signal generated by the first power converter circuit in a transmit mode, and generates a second received AC power signal at the operating frequency from a second magnetic field generated by the second wireless power circuit while in the region of wireless power transfer in a receive mode.
18 . The method of claim 16 , wherein the second wireless power circuit generates the first received AC power signal at the operating frequency from the first magnetic field generated by the first wireless power circuit while in the region of wireless power transfer in a receive mode, and generates a second magnetic field in the region of wireless power transfer at the operating frequency based on the second AC power output signal generated by the second power converter circuit in a transmit mode.
19 . The method of claim 16 , wherein the second power converter circuit, operating as a bidirectional power converter, converts the first received AC power signal at the operating frequency to the first DC power output signal in a receive mode, and to convert a DC power input signal to a second AC power output signal at the operating frequency in a transmit mode.
20 . The method of claim 13 , further comprising adapting to a load presented to the second power converter by adjusting at least one of a duty cycle of a pulse width modulation switching waveform of the first and second power converter and the operating frequency.
21 . The method of claim 13 , further comprising controlling a level of power delivered to a load presented to the second power converter by adjusting at least one of a duty cycle of a pulse width modulation switching waveform of the first and second power converter and the operating frequency.
22 . The method of claim 13 , further comprising maintaining a power transfer efficiency of the system by adjusting at least one of a duty cycle of a pulse width modulation switching waveform of the first and second power converter and the operating frequency.