A Reliability Evaluation Method of Distribution Grids Considering Distributed Flexible Resources

Evaluating the operational reliability of distribution grids is often computationally intensive due to the need to assess a vast number of system states influenced by uncertainties in renewable energy outputs, load variations, and random component outages. This paper introduces a Load Feasible Region (LFR) method designed to significantly accelerate the reliability evaluation process. The LFR for each state, represented as a polyhedron in the load space, is precomputed offline. The inner points of the LFR correspond to loads that meet system operational constraints. During operation, the precomputed LFR is efficiently adjusted to account for distributed flexible resources fluctuations with minimal computational overhead. Optimal load shedding for each state is then determined by calculating the minimum Manhattan distance to the LFR boundary. Several case studies are provided to illustrate the proposed method's computational efficiency and scalability.