Wireless power transmission in electric vehicles

Abstract

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.

What is claimed is: 
     
         1 . An apparatus, comprising:
 a conductive charging interface (CCI) configured to receive a first power signal;   an antenna circuit configured to wirelessly receive, via an electromagnetic field from a transmitting device, charging power to charge a battery of a vehicle, and to provide a second power signal based upon the received charging power; and   a battery electric vehicle (BEV) charging system shared by the CCI and the antenna circuit, the BEV charging system comprising:   a switching circuit configured to selectively couple the BEV charging system to the CCI or the antenna circuit;   a power output terminal coupled to the battery; and   a power converter circuit operably coupled between the switching circuit and the power output terminal,   wherein when the BEV charging system is operably coupled to the CCI, the first power signal from the CCI is input to the power converter circuit, and   wherein when the charging circuit is operably coupled to the antenna circuit, the second power signal from the antenna circuit is input to the power converter circuit.   
     
     
         2 . The apparatus of  claim 1 , wherein the second power signal is a low-frequency (LF) power signal, the apparatus further comprising:
 a rectifier circuit operably coupled between the antenna circuit and the switching circuit, and configured to convert the LF power signal to a DC power signal;   wherein when the charging circuit is operably coupled to the antenna circuit, the DC power signal is converted by the power converter circuit to provide an output power signal to the power output terminal.   
     
     
         3 . The apparatus of  claim 2 , wherein:
 the BEV charging system is bidirectional, operating in either a grid-to-vehicle mode or a vehicle-to-grid (V2G) mode, and the power output terminal further serves as a DC power input terminal, wherein the power converter circuit comprises a bidirectional power converter.   
     
     
         4 . The apparatus of  claim 3 ,
 wherein the rectifier circuit comprises a bidirectional inverter/rectifier circuit, and   wherein when the BEV charging system is operating in V2G mode and the BEV charging system is operably coupled to the antenna circuit, the bidirectional inverter/rectifier circuit converts DC power received from the bidirectional power converter to an LF power output signal for wireless power transfer.   
     
     
         5 . The apparatus of  claim 1 , wherein the BEV charging system further comprises an AC/DC converter circuit to convert the first power input signal from AC power to DC power. 
     
     
         6 . The apparatus of  claim 5 , wherein the AC/DC converter circuit is operably coupled between the CCI and the switching circuit. 
     
     
         7 . The apparatus of  claim 5 , wherein the AC/DC converter circuit is operably coupled between the switching circuit and the power converter circuit. 
     
     
         8 . The apparatus of  claim 5 , wherein:
 the BEV charging system is bidirectional, operating in either a grid-to-vehicle mode or a vehicle-to-grid (V2G) mode;   the power output terminal further serves as a DC power input terminal;   the power converter circuit comprises a bidirectional power converter; and   when the BEV charging system is operating in V2G mode and the BEV charging system is operably coupled to the CCI, the AC/DC converter converts DC power received from the bidirectional power converter to an AC power output signal.   
     
     
         9 . The apparatus of  claim 1 , wherein the BEV charging system is bidirectional, operating in either a grid-to-vehicle mode or a vehicle-to-grid (V2G) mode, and the power output terminal further serves as a DC power input terminal. 
     
     
         10 . The apparatus of  claim 9 , wherein the power converter circuit comprises a full bridge inverter/rectifier. 
     
     
         11 . The apparatus of  claim 9 , wherein the power converter circuit comprises a fully symmetric full bridge inverter/rectifier. 
     
     
         12 . The apparatus of  claim 11 , wherein the power converter circuit further comprises four bidirectional active switch cells. 
     
     
         13 . A method, comprising:
 receiving a first power signal at a conductive charging interface (CCI); and   wirelessly receiving, at an antenna circuit, via an electromagnetic field from a transmitting device, charging power to charge a battery of a vehicle, and providing a second power signal based upon the received charging power; and   in a battery electric vehicle (BEV) charging system shared by the CCI and the antenna circuit and having a power converter circuit operably coupled between a switching circuit and a power output terminal,   using the switching circuit to selectively couple the BEV charging system to the CCI or the antenna circuit;   when the BEV charging system is operably coupled to the CCI, coupling the first power signal from the CCI to the power converter circuit;   when the charging circuit is operably coupled to the antenna circuit, coupling the second power signal from the antenna circuit to the power converter circuit; and   providing power from the power converter circuit to the battery via the power output terminal of the BEV charging system.   
     
     
         14 . The method of  claim 13 , wherein the second power signal is a low-frequency (LF) power signal, the method further comprising:
 when the charging circuit is operably coupled to the antenna circuit,   in a rectifier circuit operably coupled between the antenna circuit and the switching circuit, converting the LF power signal to a DC power signal;   in the power converter circuit, converting the DC power signal into an output power signal, and   providing the output power signal to the power output terminal.   
     
     
         15 . The method of  claim 14 , wherein:
 the BEV charging system is bidirectional, the power converter circuit comprises a bidirectional power converter, and the rectifier circuit comprises a bidirectional inverter/rectifier circuit, the method further comprising:   alternatively operating in a grid-to-vehicle mode and a vehicle-to-grid (V2G) mode, wherein the power output terminal further serves as a DC power input terminal when operating in the V2G mode; and   when the BEV charging system is operating in V2G mode, and the BEV charging system is operably coupled to the antenna circuit,   in bidirectional inverter/rectifier circuit, converting DC power output received from the power converter circuit to an LF power output signal for wireless power transfer.   
     
     
         16 . The method of  claim 13 , further comprising using an AC/DC converter circuit to convert the first power input signal from AC power to DC power. 
     
     
         17 . The method of  claim 16 , further comprising converting the first power input signal from AC power to DC power between the CCI and the switching circuit. 
     
     
         18 . The method of  claim 16 , further comprising converting the first power input signal from AC power to DC power between the switching circuit and the power converter circuit. 
     
     
         19 . The method of  claim 16 , wherein:
 the BEV charging system is bidirectional, the power converter circuit comprises a bidirectional power converter, and the rectifier circuit comprises a bidirectional inverter/rectifier circuit, the method further comprising:   alternatively operating in a grid-to-vehicle mode and a vehicle-to-grid (V2G) mode, wherein the power output terminal further serves as a DC power input terminal when operating in the V2G mode;   when the BEV charging system is operating in V 2 G mode and the BEV charging system is operably coupled to the CCI, using the AC/DC converter to convert DC power received from the power converter circuit to an AC power output signal.   
     
     
         20 . An apparatus, comprising:
 a conductive charging interface (CCI) configured to receive a first power signal;   an antenna circuit configured to wirelessly receive, via an electromagnetic field from a transmitting device, charging power to charge a battery of a vehicle, and to provide a second power signal based upon the received charging power; and   a battery electric vehicle (BEV) charging system shared by the CCI and the antenna circuit, the BEV charging system comprising:   a switching circuit configured to selectively couple the BEV charging system to the CCI or the antenna circuit;   a power output terminal coupled to the battery; and   means for power conversion operably coupled between the switching circuit and the power output terminal,   wherein when the BEV charging system is operably coupled to the CCI, the first power signal from the CCI is input to the means for power conversion, and   wherein when the charging circuit is operably coupled to the antenna circuit, the second power signal from the antenna circuit is input to the means for power conversion.