Multi-time Scale Control Strategy of Distribution Network Based on SOP and Energy Storage

Soft open point (SOP), as a new type of distribution device, will greatly improve the economic performance, flexibility and controllability of the distribution system. In this paper, a scheme of adding energy storage device on the DC side of SOP is proposed to deal with the stochastic fluctuation of distributed generation and load in distribution network, and a multi-time scale optimization strategy based on SOP and energy storage device is presented. In a long time scale, the set-point of SOP/energy storage is controlled through the global optimization strategy of distribution network to realize the economic operation of the system. In a short time scale, the set-point of SOP/energy storage is dynamically adjusted to smooth the power fluctuation of high penetration distributed generation. A 33-bus distribution network was used to demonstrate the effectiveness of the proposed method. Results showed great benefits of SOP and energy storage combination installed in power loss reduction, voltage profile improvement, as well as its capability to accommodate high distributed generation penetrations.