A Double-Side Feedback Pulse Train Control for the Output Voltage Regulation of Two-Stage Wireless Power Transfer System

Pulse Train (PT) control is a nonlinear voltage regulation method with favorable characteristics of quick response time and simple structure. In this paper, a PT-based feedback control strategy is proposed for stabilizing the output voltage of two-stage wireless power transfer (WPT) systems. Low-frequency voltage oscillations can be observed in PT controlled front-stage power converters, which significantly degrades the output power quality of the WPT system. To solve this problem, by using feedback variables sampled from both output sides of a power converter and WPT, a capacitor current and output voltage feedback PT (CC&OV-PT) controlled two-stage WPT system is further devised in this paper. A discrete time model of the two-stage WPT system is established, and the performance of low-frequency voltage oscillations suppression for the double-side feedback CC&OV-PT controlled WPT system is analyzed. Simulation and experimental verification have been conducted, both of which show that the CC&OV-PT controlled WPT system achieves fast response with effective low-frequency oscillation suppression.