Research of Chain Circuit STATCOM Based on CPS-SPWM Modulatio

In view of problem that nonlinear and impact load inject plenty of reactive power and harmonic wave into coal mine power grid, the paper researched chain circuit STATCOM based on CPS-SPWM modulation. It introduced main circuit structure of chain circuit STATCOM; for two modulations of unipolar CPS-SPWM and bipolar CPS-SPWM in chain circuit STATCOM, it used Matlab to analyze differences between unipolar CPS-SPWM modulation and bipolar CPS-SPWM modulation based on H-bridge basic module and cascade H-bridge, the simulation result showed that waveform quality of unipolar CPS-SPWM modulation is superior to one of bipolar CPS-SPWM modulation, so chain circuit STATCOM should select unipolar CPS-SPWM modulation; it used Matlab/Simulink platform to make simulation for chain circuit STATCOM based on unipolar CPS-SPWM modulation under different modulation ratios, the simulation result showed that the chain circuit STATCOM has characteristics of good output waveform, low harmonics and strong expandability.