Reducing standing phase angles via interior point optimum power flow for improved system restoration

Maximum limits for standing phase angles (SPA) must be imposed upon network loop closure, during the transmission system restoration process. These limits reduce the risk of damage in generation and transmission equipment. This paper presents an interior point optimum power flow (OPF) tool, whose objective function to be minimized is the deviation of active power generation and/or load shedding. The maximum limits of SPA are modeled as additional constraints. A practical restoration problem in one large area of the Brazilian interconnected system was analyzed and the results indicated the effectiveness of the proposed technique.