Research On The New Method Of MPPT And Islanding Detection In Pv Grid-connected Power Generation System

With the rapid development of the global economy and the steady increase in the population, the environmental pollution and ecological imbalance caused by fossil fuels and other issues are becoming the serious obstacle of constraining to socio-economic development and even threatening to the survival of mankind. Application of new energy sources is becoming the world's hot spots .Solar energy resources are one of the most abundant renewable energy sources and shows unparalleled broad space for development and application prospects for its no pollution, no noise, easy maintenance and so on, is internationally recognized as the ideal alternative energy sources.This paper analyzes the development status and the basic theory of the solar photovoltaic system in detail, gives a detailed analysis and research on grid power system topology, the maximum power point tracking, control method, parameter selection, as well as the island effect problem.To TMS320LFDSP2407 as the core, achieve the main circuit, circuit protect, signal acquisition, parameter selection and other functions, provide a reliable application platform. Improve the existing method, proposed a new type of PWM maximum power tracking method based on the analysis of current maximum power point tracking (MPPT) method. Disturbance observation method and this method are compared by MATLAB simulation, the results show that: when sunshine changes and keeps stable, this method obtains better results.Conduct a comprehensive description and analysis of the detection methods of common island effect, and improve the existing solution. Carry out using MATLAB simulation confirms that this detection method had an small impact on power quality, its detection is simple and convenient, system is stable and feasible.