The Research Of Photovoltaic Grid-connected System Islanding

Along with coal and oil as the representatives of the fossil energy are exhausted, develop clean and renewable energy has become an important strategy for the world’s economic and social sustainable development. Among them, the use of solar energy is especially popular, progress of solar photovoltaic cells and photovoltaic power generation technology, and solar energy inexhaustible, clean and pollution-free characteristics, the solar energy has become one of the most important new energy alternative to fossil energy. However, the photovoltaic power generation as a new technology, there are still many problems in technology, such as the control of grid connected photovoltaic system, solar tracking, anti island effect. Among them, anti islanding techniques related to the effective use of solar energy photovoltaic grid connected system, introduces and analyzes the main focus of the islanding effect for the solar photovoltaic grid connected system.Firstly, the characteristic of solar photovoltaic power generation system structure, key technology, and carries on the system analysis, and then analyzes the damage mechanism of islanding effect and the islanding effect, and introduces the research status at home and abroad and the island of anti islanding detection criterion. The main analysis of the current anti islanding techniques, such as:the passive detection method is more common and active detection methods, analyses their principle. And according to its principle, analyzes the advantages and disadvantages of various detection methods and application scope. And introduced the evaluation method for islanding detection performance.This paper focuses on the active islanding detection method to do a more in-depth study, a detailed analysis of the principle of active detection method, compares the effectiveness of various methods and their advantages and disadvantages. At the same time, put forward a new improved method of detection, that is to put forward an improved algorithm for automatic phase shift islanding detection method, the automatic phase shift detection method is simple and feasible, and expounds its principle, and analyzes the possibility of simulation verify the effectiveness of the.