Overload Protection Scheme to Reduce Cascading Outages Considering Thermal Line Limits

Power systems need the capacity to withstand multiple-fault situations where customer supply losses are in-evitable. Considering the high complexity and time-intensive nature of manually analyzing such instances, utilizing fully automated systems and decision support tools can be far more efficient at handling cascading outages. We propose an optimal overload tripping scheme (OOT) that reduces load loss by avoiding uncontrolled cascading outages. Building upon prior research to minimize load loss, the computational burden is further managed by an efficient restriction on the search space. Temperature Dependent Power Flow (TDPF) is used to analyze the thermal inertia of overhead lines along with their initial temperature and current magnitude to determine the amount of time available for overload mitigation. Simulation case studies conducted on a high-voltage (HV) benchmark grid are used to assess the method's efficacy and requirements.. The load loss after implementing the proposed OOT, the previous OOT, and an uncontrolled cascade of outages are compared. After reviewing the results, the feasibility of integrating the proposed OOT into real grid operations is discussed.