Phase control of series resonant converter

A phase-controlled series resonant DC-DC power converter is described, analyzed, and experimentally verified. The circuit consists of a phase-controlled inverter and a Class D current-driven rectifier. The phase-controlled inverter comprises two conventional Class D inverters driving the same AC load. The phase shift between the voltages that drive the MOSFETs is varied to control the AC current of the inverter and thereby regulate the DC output voltage of the converter. A frequency-domain analysis is used to derive basic equations which govern the circuit operation. The important advantage of the converter is that the operating frequency can be maintained constant. Unlike most phase-controlled converters, the load of each switching leg is inductive for operation above resonance and capacitive for operation below resonance, which is a very desirable feature. The theoretical and experimental results obtained were in good agreement