Investigation On Network Reconfiguration During Power System Black-Start

Black-start is the process of the system restoration after blackout of the entire power system. The restoration process is usually divided into three stages: black-start, network reconfiguration and load restoration. The network reconfiguration consists of two sequential steps: the first step is to determine an optimal target network as restoration guidance and the second to make up the sequence of switching operations (restoration procedure) to bring a faulted system into the obtained optimal target system while maintaining a certain level of security. This paper is mainly concerned with the first step due to its primal importance and inherent complexity. The network reconfiguration is treated as a nonlinear optimization problem with an objective function to maximize the proportion of important load restoration. The problem is solved by a discrete particle-swarm optimization algorithm. The paper also discusses the influences of network reconfiguration on determination of black-start plans. The effectiveness of the propose algorithm is validated by the numerical results on the IEEE 30-bus system and IEEE57-bus system.