A Novel Controller Strategy for LCL Damping in Reduced DC Voltage fed D-STATCOM

Abstract

This work focuses on a new topology-control based D-STATCOM solution with reduced DC bus voltage requirement and with an excellent grid side performances. The proposed concept consists of a main shunt converter and a series converter with a transformer to achieve the desired DC bus reduction. The active damping based on capacitor current feedback and associated additional capacitor current sensor requirement are eliminated by using a proposed double controller structure for series and shunt converters with only series current as a controlled variable. Moreover, the stability related issues based on converter inductor selection is studied extensively for the above controller and superiority of the proposed concept is demonstrated. The proposed solution is verified through simulation studies and through a scaled-down experimental prototype.