Research On Micro-Inverter System Based On Power Line Carrier

With the development of networking technology and distributed photovoltaic power generation,an efficient demand of consumer market,has the function of remote monitoring,products for photovoltaic grid connected inverter small household photovoltaic power generation.The domestic photovoltaic inverter than traditional photovoltaic inverter power plant is smaller,so it can overcome the disadvantages of sunshine dispersion,with a more flexible and widely used scene,set of photovoltaic power generation system with lower cost and benefit to the home market.The developed family of grid connected inverter,using interleaved flyback topology,makes the inverter has the advantages of high efficiency,low system cost,small space occupation and so on.Firstly,this paper introduces the background and significance of the research,and analyzes the research status of the key technologies,such as photovoltaic inverter,grid connected inverter,power system monitoring and so on.The hardware parameters of the micro grid connected inverter are analyzed and calculated in detail.The main components of the input decoupling capacitor,flyback transformer,main switch tube and clamp capacitor are analyzed and designed.Analysis and design of the critical voltage and current signal conditioning circuit.The digital control software architecture based on microprocessor control is designed.The system of the timing control of photovoltaic micro inverter,the maximum power tracking algorithm based on the perturbation and observation,combined with a feedforward compensator and the grid connected current loop compensator to complete the main function of photovoltaic micro inverter.In this paper,the advantages and disadvantages of the distributed system,power line carrier and wireless communication system are introduced.The RISE3501 E chip is used to design the hardware circuit of the carrier,such as carrier transmission,carrier reception,signal decoupling,power supply and so on.A small signal model of grid connected inverter based on power line carrier is established.By comparing the Matlab system before and after correction of the open-loop transfer frequency characteristics,build a model of photovoltaic micro inverter and grid current controller based on the Simulink model to verify the correctness of theoretical analysis,and developed a micro photovoltaic inverter prototype.