A novel DC voltage control for a cascade H-bridge multilevel STATCOM

Cascade H-bridge multilevel inverter is a best candidate for static VAr compensation in medium and high voltage applications. The topology consists of several capacitors to provide dc link voltage support for H-bridge inverters. Regulation of the dc link voltages at the required levels is a major research challenge in VAr compensated inverters. This paper presents a novel and simple control strategy for a five level cascade H-bridge multilevel STATCOM. The scheme realizes the required objectives with fewer PI controllers and produces accurate results. Rigorous simulation study is carried out in MATLAB SIMULINK to validate the control scheme and results are presented.