Research And Design Of Micro-inverter Photovoltaic Grid-connected Generation System Based On FPGA

Due to global energy shortage and environmental pollution increasing since the 21 st century. Solar energy is one of the green clean energies, is gradually moving from the basic energy. Photovoltaic power generation has become the focus of attention and the development of new industries in the world, mainly in the form of photovoltaic power generation as the use of solar photovoltaic, will get rapid development.Traditional centralized anti photovoltaic systems, It has anti-poor shadow, complex system capacity expansion, complex of installation and maintenance features. As the PV inverter fails, the entire power system caused great impact. Distributed PV system uses the micro grid-connected PV inverter. That is, each photovoltaic panels equipped with a separate micro-inverter. It has a high power generation efficiency, simple to install, hot swappable, easy to achieve the maximum power point tracking, etc.Firstly,This paper studies the maximum power point tracking technology for photovoltaic systems. As a constant voltage method, perturbation and observation method, incremental conductance method, and do the relevant analysis and comparison.Secondly, This paper do a detailed study on PV micro inverter choose,PV micro inverter in this paper chooses CCM flyback inverter topology. Pre-DC / DC use interleaved flyback converter,it makes that the photovoltaic panels output pressure is increased.After grade DC / AC uses a full-bridge inverter circuit, it inverse DC into AC. the control method of it is simple, high efficiency power transfer and high power generation efficiency.The paper also built photovoltaic grid simulation model of the whole system based on Matlab / Simulink simulation platform, and do the performance of the whole system simulation analysis and verification,after that, System islanding state when the system is also carried out also do a detailed simulation and analysis.Finally, According to the micro-grid PV inverter technology parameters, Using ALTERA company Cyclone IV FPGA family EP4CE10E22C8 N as the core of the control circuit chip, and then conduct the hardware and software design of the micro grid-connected PV inverter. And on the third-party simulation platform-Modelsim, Software algorithm is validated, the experimental results verify the correctness of the algorithm.