A method for improving output current waveform of series-resonant AC link inverter

This paper presents a method of improving the output current waveform for a series resonant AC link inverter by amplitude control and pulse density modulation (PDM). Because the analysis of series resonant circuits is complex, the authors consider three modes of the circuit and then derive the turn-over time which controls the average of output current for a half cycle. With simulation results based on a voltage source of 100 V and a resonant frequency of 40 kHz, a method of improving the output current waveform by controlling the turn-over time is also given in detail.<>