Loss Analysis of Rectifier Circuit and Its Optimization Technique in Wireless Power Transfer System

Abstract

As an important part of the magnetic resonant wireless power transfer technology, the rectifier circuit plays a key role. The quality of its performance will directly affect the transmission efficiency of the WPT system. This paper proposes the full-bridge and voltage-doubler rectifier loss calculation models combined with the circuit structures and operating principle. On this basis, it reveals that the voltage-doubler rectifier circuit can greatly reduce the loss and improve the overall efficiency of the WPT system in the case of high voltage and low current, and the optimized effect will be greater as the decreasing of equivalent resistance ESR of the filter capacitor. Experimental results show that the efficiency of the WPT system based on the voltage-doubler rectifier structure can be increased by 2% compared to the traditional method, and the optimized efficiency of the WPT system is 93% at rated operating conditions, which verifies the theory analysis to be correct and flexible.