Multi-objective operation optimization of active distribution network based on three-terminal flexible multi-state switch

Abstract

To operate the distribution network properly is a great challenge when numerous intermittent distributed generators are involved. A novel approach for solving this issue is proposed in this paper, which is based on the three-terminal flexible multi-state switch. The three-terminal flexible multi-state switches, which are controllable, are adopted to replace the traditional tie switch and to increase the flexibility of distribution network operation and control. The timing characteristics of distribution network operation are considered, and the controllable load and the three-port flexible multi-state switch are introduced into this methodology. A multi-objective operation optimization model for an active distribution network is developed, i.e., the objective functions are designed to minimize the operating cost of the distribution network and to minimize the voltage deviation in multiple periods with consideration of demand response according to the characteristics of the active distribution network. The effectiveness of the proposed method is validated based on the IEEE 33-node test feeder by the combined Particle Swarm Optimization algorithm. The results show that the coordinated optimization of the flexible multi-state switch and the demand response improve the distribution network voltage levels significantly, which will not only bring the economic efficiency but also improve the safety and reliability of the system.