Analytical Stochastic Power Flow for Power Systems with High Penetration of Renewable Energy

For online dispatch, it is necessary to formulate the influence of ultra-short-term forecasting errors of renewable energy (RE) to guarantee the power grid safety. As a basic evaluation tool, the stochastic power flow (SPF) method should meet the efficiency requirements of online decision making. In this paper, the Cauchy distribution, which has high peak and fat tail characteristics, is used to fit the shape of RE ultra-short-time forecasting errors. With the formulation of the Cauchy distribution, an analytical SPF method considering the uncertainty of RE is proposed. This analytical SPF method ensures a fast calculation speed with high accuracy. Therefore, it is applicable for real-time applications. Numerical test results justify the superiority of the proposed Cauchy method in terms of accuracy compared to conventional methods.