A Novel 12-Pulse 3-Level Inverter for STATCOM Using Selective Harmonic Elimination Modulation

The static synchronous compensator(STATCOM) using power electronics as a shunt device of the Flexible AC Transmission Systems (FACTS) is attracting an increasing interest in power system research and in electric utilities. This paper proposes a novel multi-level structure topology with zigzag transformer for three-level inverter used in STATCOM. Moreover, selective harmonic elimination pulsewidth modulation (SHEPWM) is applied in the topology to reduce switching frequency while restraining harmonics at the same time. Simulation models are set up with Matlab. Finally, SHEPWM method for the proposed topology is realized with digital signal processor (DSP) and experiments are given for verification.