Investigation of Five Level Flying Capacitor and CHB Multilevel Inverter for D-STATCOM Applications

Abstract

D-STATCOM (Distribution Static Synchronous Compensator) is a versatile solution for mitigation of power quality related problems in distribution system. It can be configured and controlled in variety of ways depending upon the requirements of mitigation of particular problem. The control schemes are tuned to provide solutions for voltage regulation, reactive power compensation, power factor correction or harmonics mitigation. The heart of the D-STATCOM is a voltage source inverter. This voltage source inverter may take form of simple 2/3 level inverter or a multilevel inverter. The multilevel inverters,although being expensive, are preferred due to their several advantages. Therefore, in this paper, two configurations of multilevel inverter namely flying capacitor and cascaded H-bridge are used to configure a D-STATCOM. The D-STATCOM is controlled with dq theory based control technique. The results presented to compare the performance these two configurations for power quality parameters of harmonics and stress on switching devices.