Static Security Risk Assessment of Power Systems Considering State Uncertainty and Equipment Out-of-Service Uncertainty

How to accurately and efficiently assess power system static security risk, taking into account both renewable energy output uncertainty and equipment out-of-service uncertainty, has always been valued by electric power companies and researchers. To address this issue, this study proposes a set of indices for power system static security risk assessment, along with their fast calculation method and a method for identifying vulnerable points. First, we apply the new adaptive sparse pseudo spectral approximation method (NA-SPAM) to stochastic power flow calculations, thereby realizing the efficient computation of stochastic power flow for the first time and laying a solid foundation for the system security assessment. Subsequently, a set of indices for static security risk assessment based on the results of stochastic power flow calculations, which consider the impacts of both state uncertainty and disturbance uncertainty, is designed and calculated. In addition, the vulnerable points of the system are identified. The sample results demonstrate the effectiveness and superiority of the proposed set of indices and algorithm. The set of indices and its calculation methods proposed in the paper promote the progress of research and engineering applications of security risk assessment in the new power system.