Hierarchical Reliability Evaluation to Security and Stability Control System of Power Systems

The security and stability control system is the 2nd defense for the power system. Its reliability is critical to the normal operation of power systems, which is studied with the case of a practical stability control device in this paper. Based on the hardware configuration and control strategies, the fault tree analysis (FTA) is applied to derive the hierarchical modeling. Probabilistic analysis based on the logic of the unavailable events is performed to quantify the reliability of the device. The absolute and relative sensitivities are introduced to quantify the parametric sensitivities and find the vulnerable modules possibly yielding unavailability of the stability control device. The numerical results are provided to validate the feasibility and accuracy of the proposed model. The study is beneficial to power system stability and security.