A Novel Three-phase Converter Using Three-phase Series Chopper

Abstract

This paper proposes a novel three-phase converter using three-phase series chopper. The proposed circuit is composed by three switching devices, three-phase diode bridge, input reactors, and LC low pass filter. In the conventional circuit which combines three-phase diode bridge and boost voltage chopper, to obtain sinusoidal input current the output voltage must be twice or three times larger than the maximum input line voltage. However, in the proposed circuit, the input current can be controlled to be sinusoidal also when the output voltage is same as the maximum input line voltage. This can be achieved because in the proposed circuit the discharging current of the reactors does not flow through the voltage source. The control method of the proposed circuit is as simple as the one of conventional circuit since all the three switching devices are simultaneously turned on and off.This paper discusses about the theoretical analysis and the design of the proposed circuit. In addition, simulation and experimental results are reported. The proposed circuit has obtained 93% as the efficiency, and 99.7% at 1.3kW load as the input power factor.