A new approach of hierarchical optimization to distribution system service restoration

The paper proposes a new algorithm for service restoration in distribution systems. The proposed method makes use of the hierarchical optimization of tabu search to speed up computation time. The formulation of service restoration may be expressed as a combinational optimization problem that finds the optimal route to recover the service. Recently, the deregulated and competitive power markets have made distribution systems more complicated in the sense that operators have to consider the effect of distributed generation (DG) in distribution systems. Therefore, formulating the service restoration problem becomes more complicated. A fast method is proposed to decompose a distribution system with DG into subsystems and determine the service restoration in a hierarchical optimization way. The proposed method is demonstrated in a sample system. A comparison between the proposed and conventional methods is made in terms of solution quality and computation time.