Research and Analysis of SPWM Modulation Strategy Based on NSBI Converter

In the renewable energy power generation system such as wind and light, a new type of nine-switch converter (NSBI) with boost function can not only realize two-terminal energy output, but also reduce the number of traditional back-to-back extension devices and save design cost. In this paper, the different switch states in the 27 switches are analyzed, and three different SPWM modulation strategies are proposed corresponding to different switch combinations. The simulation results show that the optimized SPWM can obtain more stable DC side voltage and up-down output voltage than the SPWM with equal carrier and shared boundary value, and it is convenient to access different AC loads, so further research is carried out.