Series resonant DC-link AC/DC power converter for a V/F controlled motor drive

A new AC/AC power converter topology based on zero current switching is proposed to reduce switching losses. The topology enables pulse width modulation (PWM) control. The scheme implements "peak-limiting" of resonant current by a simple diode clamp and does not use dedicated devices for the start-up. Improved switch utilization and reduced part-count could be cited as the merits of the topology. It is experimentally verified that the current pulses could be controlled to achieve constant V/F operation. A mode controller which controls input line currents is introduced and digitally verified.