Analysis On Conducted Noise Characteristic And Efficiency Of SiC Grid-connected Inverter

This thesis investigate the impact of the SiC MOSFET on grid-connected inverters with respect to conversion efficiency and EMC.In chapter 1,the influence of SiC devices on EMI noise level to grid-connected inverter is discussed and the common modeling method of EMI noise source and propagation path are introduced,as well as the exiting inverter EMC model.Then the improvements on efficiency and power density of using SiC MOSFET in three-phase inverter are reviewed.Chapter 2 mainly discusses the EMC modeling of SiC MOSFET grid-connected inverter.EMI noise source model is setup through the analysis on SiC MOSFET characteristic.Damping to noise transmission is introduced to indicate the impact of ther inverter power loss on EMI noise.Then the simulation model EMC and analytical EMC model of the grid-connected inverter are established.Finally the analytical EMC model and simulation model are verified with experimental results.Moreover,the efficiency performance of SiC inverter and Si IGBT inverter are also compared.In chapter 3,the efficiency evaluation and loss break down of trech gate SiC inverter,planar gate SiC inverter and Si IGBT inverter are performed based on the loss model of two-level inverter.Then the three 10 kW inverter prototype are built to verify the theoretical efficiency curve.