Research on cascaded multilevel inverter and its application in STATCOM

Abstract

Because of the broad application of multilevel converters in the high-power area, a cascaded multilevel voltage-source inverter with phase-shifted SPWM (PS-SPWM) switching scheme is proposed as a static synchronous compensator (STATCOM). This can eliminate the bulky and weighty transformers and reduce power loss. In addition, the equivalent carrier frequency can be doubled and the output harmonics will be reduced compared with the STATCOM being put into operation. The operating principle and control methods are analyzed in detail and the feasibility is validated by simulation with MATLAB.