Risk Assessment Of Power Systems With Photovoltaic Power Plants

China has a bright future for the development and application of the new energy generation resources. Among them, the photovoltaic power generation has strong randomness and volatility, and with the continuous expansion of its scale, it results in the corresponding operational risk for the whole power system. At the same time, the traditional power supply, power lines and other electrical equipment still exist random outage. these factors seriously affect the power quality and even the stability of the power system.Therefore, it will be significant to study the inference of photovoltaic power station to power system and to carry out the operational risk assessment of power system with photovoltaic power station. The main work of this thesis is performed as follows:1. In view of the aging problem of the generator, this thesis presents a transformer outage model based on aging factors and it is based on the real-time operational conditions of generator outage model. Considering the outage factors of the transmission line, the outage model of transmission line is established based on the aging factors and the power flow factors. It establishes the load probability model based on the instability of the actual power system operation. Considering the randomness and volatility of the output of photovoltaic power stations, this thesis analyzes the factors of the photovoltaic power stations, such as composition and output, and it also establish the models of the solar irradiance and photovoltaic power station which lays the foundation for the risk assessment of power system with photovoltaic power stations.2. Based on the theory of risk, this thesis puts forward the risk index for the power system to quantity the risk. According to the different impact of each risk index on the system,this thesis uses Analytic Hierarchy Process to obtain the weight value of each index and to get the comprehensive risk index. According to the different risks, this thesis presents a risk assessment method of power system based on non-sequential Monte-Carlo method. Based on the load reduction optimization model, IEEE-RTS 24 system is simulated to verify the reliability and feasibility of the method.3. According to the outage models of generator, power line and other electrical equipment and the models of the solar irradiance and photovoltaic power station, this thesis puts forward a power system risk assessment method with photovoltaic power stations based on non-sequential Monte-Carlo method and calculates the set risk index to analyze the risk level based on the IEEE-RTS 24 system. At the same time,it does research on the influences of different positions and configurations of photovoltaic power stations to verify the reliability and feasibility of the method. In addition, based on the concept of the real-time importance of nodes and utility theory, this thesis gives the risk utility index of the power system and compares with the traditional risk index.