Study On Technologies Of Distributed Photovoltaic Power Plant Conneting To The Grid

Zhangjiakou area is rich in solar energy resources. With government’s active promotion on the development of the PV industry in recent years, a large number of distributed PV power generation will be connected to the grid.This paper firstly reviews the domestic and foreign history of the PV development. PV power generation system installed capacity has reached an unprecedented high level in strong trend. Then it studies the principles of distributed PV power generation, on which PV cell simulation model is established to obtain the conclusion that the output characteristics of PV cell will show strong non-linear characteristic, and maximum power fluctuates. It also explores the common method of tracking the maximum power output value. The PV cell characteristics and maximum output power control strategy has negative effects on the distribution network accessed to.Thirdly this article summarizes some characteristics of PV power, and discusses the impact of the PV access to the distribution network. It analyses from several aspects such as the power quality, the injection of the DC component, the short circuit fault, the islanding, the distribution network planning and protective relaying, and puts forward some measure to reduce the impact in on-site work.This article focuses on the distributed PV power generation access system design. With the analysis on the status of Zhangjiakou Power Grid, distributed PV power plants can be selected as the nearest substation standby switch as an access point. According to the characteristics of PV power plants and grid requirements, equipment type can be chose. Also, this article focuses on the developing primary system access program, including send-out program, the PV power plant primary program and requirements. It formulates the secondary system access solutions, including power stations, PV grid power plant configuration, protection requirements, scheduling systems and communications program, and develops measurement device configuration plan, makes accuracy requirements clear. Finally it analyses the problem in design, and searches for solutions.In the end, this article analyses the economic benefits of the project after production from two aspects of income and expenditure. PV power generation subsidy income is mainly affected by the impact of national policies, and the progress of PV technology is the major factor affects expenditure.