Research on cascade STATCOM based on pulse step modulation

Pulse step modulation is a modulation method that combined step wave modulation and pulse width modulation. Introduced pulse step modulation into cascade STATCOM and briefly analyzed the basic principles of the pulse step modulation. Based on the characteristics of pulse step modulation, a DC-link voltage balancing control strategy is presented, which is suitable for pulse step modulation. The method regulates the modulation M of the H-bridge which using pulse step modulation and achieves the DC-link capacitor voltage balance of all H-bridges. The simulation model based on Matlab shows the feasibility and effectiveness of the proposed method.