Mobile QR Code QR CODE : The Korean Institute of Power Electronics
Title Alleviate Current Distortion of Dual-buck Inverter During Reactive Power Support
Authors Sanghun Han ; Younghoon Cho
Page pp.134-141
ISSN 1229-2214
Keywords Photovoltaic inverter; Dual-buck inverter; Zero-crossing distortion; Reactive power capability
Abstract This study presents a method for reducing current distortion that occurs when a dual-buck inverter generates reactive power. Dual-buck inverters, which are only capable of unity power factor operation, can generate reactive power capabilities by modifying a modulation technique. However, under non-unity power factor conditions, current distortion occurs at zero-crossing points of grid voltage and output current. This distortion is caused by parasitic capacitors, dead-time, and discontinuous conduction mode operation. This study proposes a modified modulation method to alleviate the current distortion at zero-crossing point of the grid voltage. A repetitive controller is applied to reduce this distortion of the output current. A 1 kVA prototype is built and tested. Simulation and experimental results demonstrate the effectiveness of the proposed method.