A novel common mode multi-phase half-wave semi-synchronous rectifier for inductive power transfer applications

In this study, a novel common mode multi-phase half-wave semi-synchronous rectifier is investigated for applications in wireless energy transfer. The circuit is intended to alleviate variations of the load resistance or coupling coefficient factor while maintaining high efficiency. The proposed rectifier structure is based on the connection of semi-controlled multiple half-wave rectifier topology through multiple inductors. The receiver side semi-synchronous switches are controlled to increase the system efficiency by a symmetrical phase-shifted PWM signals in response to load variations. A 700 W laboratory prototype system is designed to validate the proposed topology in terms of current, power, and efficiency. Experimental results are provided for various loads using 8 inches air gap coreless transformer, which has dimension 2.5 by 2.5 feet, with a 120 V input and a maximum efficiency of 94.8 %.