Static security risk assessment of power system considering wind speed correlation

Since multiple wind farms in a power grid are relatively close to each other,their wind speeds have obvious correlation,which has impact on the results of probabilistic load flow. Nataf transform is applied to build the sample space of wind speed correlation among multiple wind farms and the output power of wind farm with correlation is obtained. The anticipated accident set is constructed based on the present operating state of power system with wind speed correlation and the total probability theory is combined with the probabilistic load flow based on the ranked-set sampling to calculate the stochastic load flow of power system with wind speed correlation and assess its security risk. The results of RSMCS(Ranked Set Monte Carlo Simulation) for the improved IEEE 30-bus system with wind power show that,the proposed method can correctly and quickly assess the static security risk of present operating state of power system with wind speed correlation.