A Novel Hybrid Seven-level Inverter And Control Strategy

Because multi-level inverter has the advantages of small output harmonics,low device loss and high power density,it has gained wider attention and application in the field of medium and high voltage and large capacity electric transmission.A novel hybrid seven-level inverter topology and its control strategy are proposed.The main work of this paper includes the following points:(1)The research background and significance of multi-level inverters are introduced,and the research status of multi-level inverter topology and its control strategy is mentioned.(2)A novel hybrid seven-level inverter topology and its working principle are proposed.The operating mode of the inverter is analyzed and compared with two other typical seven-level inverter topologies.At the same time,the loss simulation model of the main power circuit is built.(3)The effect of the modality on the floating capacitor voltage and the neutral point voltage is analyzed.A capacitor voltage control strategy is proposed.The simulation model is built to verify the effectiveness of control strategy.(4)The main circuit of the novel hybrid seven-level inverter is designed.Experiments were performed on a multi-level experimental platform in the laboratory.The effectiveness of the control strategy was verified and the parameter performance of the topology was tested.(5)The research work of the thesis was summarized and summarized,and the direction of the next research work was put forward.