Impact of Cascading and Common-Cause Outages on Resilience-Constrained Optimal Economic Operation of Power Systems

Abstract

Common-cause and cascading outages in extreme power system conditions may challenge traditional N-k transmission security strategies. This paper proposes a resilience index (RI) to evaluate the power system adaptability to extreme conditions and establishes the resilience-constrained economic dispatch (RCED) model and solution methodology in power system operations. A three-stage outage sampling method is presented to assess the proposed RI in severe weather conditions culminating in common-cause and cascading outages. In the proposed RCED model, customized contingency constraints are introduced to represent common-cause and cascading outages in extreme events and two penalty terms are considered that can adjust power transmission flows for lowering outage risks in a power grid. An optimization method is presented to solve the RCED model efficiently with an absolute value function introduced in both objective function and constraints. A sufficient and necessary condition is proposed to ensure the optimality of the linearized solution is the same as that of the original problem. Case studies show the effectiveness of the proposed model and methodology.