A Novel Type of Single-Ended Wireless V2H System with a Supply Voltage Control and a Capacitor Selector Scheme

Abstract

This paper deals with a single-ended bidirectional WPT (Wireless Power Transfer) system for wireless V2H (Vehicle to Home) system which ensures controllability, productivity and compatibility for practical applications. The previous system had two problems. Firstly, the transmission power dramatically changes by small variation of circuit parameters. Secondly, the operating frequency for controlling the transmission power fluctuates, and it exceeds the allowable frequency band by the international standard. Proposed has been a new bidirectional WPT system with a combination of a resonant capacitor selector scheme and supply voltage control as the solution to the above mentioned two problems. Described is that the transmission power is decided by phase difference between the primary side converter and secondary side converter in the WPT system. By changing over the resonant capacitor to make the appropriate difference between power feeding and receiving resonant circuit parameters, the phase difference is maintained stable. Then the high robustness of transmission power against circuit parameter variations can be secured. On the other hand, the phase difference can be controlled by the supply voltage to the primary side converter and secondary side converter. Therefore, the transmission power can be changed from 0 to the maximum power under constant operating frequency by the supply voltage control method. As a result, the proposed system ensured controllability under the international standard, mass productivity and compatibility for the realization of the low cost and small size single-ended converters driven wireless V2H system.