Research And Design Of Photovoltaic Inverter Based On SiC MOSFET

The development of clean energy is unstoppable,and the solar energy as the representative of clean energy,has developed rapidly in recent years,and it is more and more favored by researchers.However,as the core of solar power generation,the traditional photovoltaic inverters are gradually unable to meet the new performance requirements of the new energy era.Therefore,it is urgent to develop a new photovoltaic inverter with high frequency,high efficiency and high power density that can match new energy sources.In this paper,based on a new wide bandgap semiconductor SiC device,a new soft-switching topology is proposed to further improve device efficiency,and a novel photovoltaic inverter with excellent performance is designed.The main work of this paper is as follows:Firstly,the status quo of energy at home and abroad is introduced,and the development trend of energy in the future is pointed out.The history of semiconductor power devices is reviewed and the performance differences between wide bandgap materials SiC and Si are compared.Secondly,the typical front step-up topologies such as forward,flyback,push-pull and half-bridge are introduced in detail,and the advantages and disadvantages of these topologies are compared and analyzed,and the rear step-up topologies such as half-bridge and full-bridge are also briefly introduced.Finally,based on the performance parameters of photovoltaic inverters,push-pull and full-bridge topologies are chosen as the basic topologies of the inverters.Thirdly,the common soft switching technology is introduced.A novel voltage doubling resonant topology is proposed based on the traditional push-pull resonant circuit.The working principle of the new soft switching topology is analyzed and deduced,and it is verified by simulation with Saber software.Fourthly,the hardware structure and software control strategy of the inverter are designed.The main circuit and peripheral auxiliary circuit of the inverter,such as boost circuit,power supply circuit and drive circuit,are designed in detail.The rated output power of the new photovoltaic inverter is 500 W,the switching frequency is 100 kHz,the output AC voltage frequency is 220 V and 50 HZ,and the efficiency is 93.4%.The performance meets the original design requirements.