Study On The Influence Of Photovoltaic Power Station On Distribution Network Relay Protection

PV as a new energy technology is to being favored by more and more people, while photovoltaic industry is also growing to occupy large market share in power industry. However, with the photovoltaic power plants and networks, the traditional single-ended power supply distribution network mode is changed, the interactive effects of large-scale photovoltaic power plants to the grid is becoming increasingly apparent, while the efficiency of photovoltaic power plants and networks have become the main problem of today’s photovoltaic industry. Therefore, further study of photovoltaic power plants and the net impact on the distribution of power and control strategies to improve the overall efficiency and effectiveness of photovoltaic grid has a very important significance. Maximum Power Point Tracking (MPPT) PV grid process is an important component, the control performance has largely determines the photovoltaic grid power quality and network efficiency and dynamic performance of the system.The modeling of photovoltaic cells has an in-depth discussion. Theoretical analysis of the basic model of photovoltaic cells, and based on Matlab\ Simulink simulation software, build a simulation model of photovoltaic cell physics and engineering simulation model to analyze its output characteristics. The dissertation focuses on the influence on the relay protection system after PV incorporate with the distribution network. A simulation model of PV power was built, using MATLAB software, according to the mathematical of PV cells. And the results show that it performances well. Three methods, qualitative analysis, theoretical derivation and verification with simulation, were used for conclusion. In the process of theoretical derivation, three methods, the steady equivalent, source equivalent and procedures, were used to derivate short circuit current in distribution network. Paper focuses on MPPT, Update the existing predictive control method, Applied to The MPPT control of photovoltaic grid power system, and we put forward the New MPPT strategy in the end.