A Single-Step Bidirectional Switch Commutation Strategy for PWM Controlled AC/DC Resonant Converters

摘要

AC/DC conversion may be achieved using single-stage, PWM-controlled resonant converters and has been a topic in new areas of research. Replacing either of the two bridges of a resonant converter with a single-phase matrix converter, comprised of bidirectional switching cells, has permitted the use of these topologies in AC/DC conversion applications. However, the commutation of the current during switching transitions may create catastrophic inductive voltage spiking. Traditional four-step commutation patterns increase switching losses and deadtime between switching states, which leads to increased diode conduction losses. A new one-step commutation pattern requiring only bus voltage sensing for AC/DC resonant converters with PWM control is presented in this work. This new commutation pattern is examined under four possible operating states and Matlab/Simulink® simulations are presented to establish its feasibility. A testbed is constructed to capture the key current commutation waveforms to validate the proposed commutation strategy in real-world applications.