Reliability Analysis And Operational Risk Assessment Of Bulk System Associated With Wind Farms

Wind energy has a wide distribution, cleaning, zero emissions, renewable and other advantages. And with the development of wind power technology, it is becoming recognized as the most development scale and market competitiveness of renewable energy forms. However, due to the randomness, intermittent and volatility of wind, it can’t be ignored that wind power bring the impact on the safe and reliable operation of the power system. Especially in the backgroud of wind farm scale increases year by year, it is very important to how to measure the capacity value of the wind farm accurately and how to assess the impact of wind power on the reliability and operational risks of power system reasonably. This paper conducts the following study work based on the existing relative theoretical study and the practical experience.Firstly, the method of time series analysis is used to establish the autoregressive moving average time series model of wind speed prediction, and gives the expression of wind correlation between different wind farms. The two state Markov process is used to describe the random outage of wind turbines. Based on wind turbine power output characteristic curve, establish the reliability model of wind farm with taking wake effects into account.Secondly, from the generation system reliability level, based on sequential Monte Carlo simulation, using ultra-linear convergence of parabolic method to calculate the capacity credit of wind farms. At the same time,the difference of capacity credit when different index is adapted to measure system reliability, together with the factors affect the capacity credit are also analyzed.Thirdly, from the perspective of long planning, according to the generators, lines, transformers and other components model of bulk system, combined with a reliable model of the wind farm, to build a reliability model and index of bulk system associated with large-scale wind farms.Based on IEEE-RTS79testing system, study the influence of the installed capacity of wind farms, wind farm alternative to conventional power and wind speed correlation on the reliability of bulk system respectively.Finally, analysis on the risk factors of bulk system associated with large-scale wind farms from the perspective of short run. Depending on the cause of the risk factors, it will be divided into these three categories of accidental failure modes, aging failure mode and the uncertainty of predict, then establish the model of operation risk assessment, respectively. While an index system is established to characterize the short-run risk, including the indicators of overall status, over limit extent and expected load curtailment. Based on IEEE-RTS79testing system, study the effect of wind power on the operation risk of bulk system.