A risk sensitivity-based approach to hardening power systems against catastrophic failures

This paper introduces a method based on risk sensitivity analysis to determine strategies to harden power systems against catastrophic failures. The proposed method utilizes sensitivity analysis of the risk index with respect to the control variables to identify vulnerabilities that can be corrected by strategic or tactical measures. For any initiating event, the sensitivity of the risk of load curtailments with respect to the power quality constraints such as voltage and reactive power is derived, and thereby preventive/correction actions are determined. In this paper, in addition to the insertion of compensation equipments, rescheduling of generation is considered to increase the reactive power reserve. In order to evaluate the sensitivity of the risk index with respect to the power quality constraints, voltage and reactive power constraints are incorporated with a non-linear programming optimization problem with an objective of minimum load curtailments. The model is applied on a modified version of the IEEE Reliability Test System (IEEE-MRTS). Results are reported, discussed, and thoroughly analyzed.