The Design Of Photovoltaic Inverter Based On SiC Schottky Diode

With the development of power electronic technology,power inverters are widely used.Because of energy crisis,solar energy, wind energy and other renewable green energy have been exploited in all over the world.Inverter technology plays an impor-tant role in solar energy applications. Therefore,it highly demands on the efficiency, the output waveform quality and working performance of inverter.Schottky diodes made from silicon carbide have a better reverse recovery characteristics than the sili-con Schottky diodes,and also can effectively solve the problems for switching losses,switching speed and error conducting problem caused by fast recovery silicon diode in inverter circuit,then increase the efficiency of inverter.Base on the inverter principle,this paper has designed a DC/AC sine wave inverter.Firstly,existing inverter system and the control technology used to control in-verter have been analyzed in detail.After comparison,a full-bridge structure with frequency transformer is selected as the main topology.In this design, the power MOSFET is applied in the switching unit,IR2110 and HT1112 are used in the driving circuit and the main control circuit in the inverter system respectively. It especially emphasize that the silicon carbide SBD is used as the freewheeling diode to reduce the switching losses and improve the efficiency of inverter.Secondly,according to the control principle of single-phase SPWM inverter circuit,the output filter and protec-tion circuit of inverter have been designed,and then the simulation model to be used in MATLAB/Simulink has been developed.Finally, the practical circuit test board has been done, and simulation results and partial test experimental results show that the validity of this design.