A new single phase AC to DC zero voltage soft switching converter

Abstract

A resonant boost rectifier is analyzed. The primary goal of the circuit is to produce single-phase AC line currents with very low harmonic distortion at unity power factor, thereby eliminating or reducing the size of filter components. The single-phase AC-to-DC converter consists of a boost-rectifier line conditioner connected to a resonant DC link bus. This enables zero-voltage soft switching operation of all the power devices, allowing the circuit to operate at high switching frequencies (up to 100 kHz) at high power levels (3 kW and above). The boost switch can be turned on or off at the zero voltage instants of the resonant DC link. As with resonant DC link converters, the amplitude of the AC input line current is modulated by discrete pulse modulation (DPM) of the resonant bus voltage. Furthermore, PWM (pulse width modulation) control at 100 kHz of the AC line currents can be obtained with little penalty on the system efficiency. This resonant boost rectifier is simple and reliable, achieves a high waveform quality, and operates very efficiently.<>