No abstract

The voltage and current distortion at the AC utility system due to PWM switching is generated according to the existence of source mductance(Lu) These voltage or current distortion generate electro-magnetic interference (EMI) problem to near equipment. To solve these problems, AC filter capacitor is needed to absorb the switching voltage and current distortion. However, the using of the AC filter is induced the problem of leading current, and the resonance between AC filter capacitor(Ct) and source inductance(Lu) in the utility system. In this paper, a new leading current compensation scheme for three phase PWM AC/DC converter is presented to reduce the leading current and the resonance of Cf and Lu*Lb/ (Lu+Lb). An analysis and experiments are performed to verify the proposed current control scheme by implementing a 6 kW (450VDC, 16A), 20kHz IGBT based experimental circuit.