Power Grid Reliability Assessment Considering Probability Distribution of Wind Farm Power Output

Grid-connection of large-scale wind farm brings affect on reliability of power grid due to the fluctuation of wind power output. Based on Weibull probability distribution of wind velocity and output characteristics of single wind power generating unit, a probabilistic model of possibly generated power of wind farm, in which the forced outage rate of units are taken into account, is established and this model can reflect the randomness of wind farm power output. Meanwhile, the tendency of power grid reliability indices varying with the variation of possibly generated power of wind farm is researched. On this basis, considering the defect of traditional single reliability index, the probabilistic distribution of reliability indices of power grid containing wind farm is researched to obtain the indices for the value at risk(VaR) and the conditional value at risk(CVaR) due to grid-connection of wind farm to offer foundation for the planning and operation of wind farms.