Efficiency optimization of an integrated wireless power transfer system by a genetic algorithm

This paper presents a multi-objective genetic algorithm (GA) for a wireless power transfer system composed of a full-bridge series-resonant inverter (FBSRI), a synchronous full-bridge rectifier (SFBR) and a buck converter. The proposed algorithm maximizes the total system efficiency by optimizing the switching frequency of the FBSRI and the SFBR output voltage, subject to their respective design constraints. Two application-specific integrated circuits (ASICs) respectively integrating the transmitter and receiver power-stages along with their controllers were optimized by the new algorithm. A discrete-time small-signal model of the system has been developed to analyze the stability of the wireless charger. Experimental results validating the above analysis are reported along with simulation data. The wireless power transfer system analyzed in this paper conforms to Wireless Power Consortium (WPC) specifications.