Two-Stage Optimization for Flexible Distribution Network with Multi-Terminal SOP and Battery Energy Storage

Renewable energy sources including photovoltaics (PV) are increasingly penetrating distribution networks, which has a great impact on the power flow and leads to voltage violations and increased losses. To better manage the power flow and reduce the voltage deviation in the distribution system, a multi-time scale optimization method for flexible distribution network (FDN) is proposed, which coordinates the scheduling of controllable resources in the distribution network such as soft open point (SOP) integrated with battery energy storage system (also known as E-SOP), capacitor banks (CBs), and flexible loads (FL). Firstly, in the day-ahead stage, a model for optimizing active and reactive power is developed to determine the scheduling strategies of CBs, energy storage, and the response of FL. Secondly, during the intra-day stage, a rolling optimization model is proposed utilizing the short-term prediction results of PV generation and loads to adjust the day-ahead dispatching scheme for improved performance. The proposed multi-time-scale optimization method for FDN considers the precise loss model of the E-SOP, enabling coordinated optimization between heterogeneous devices. The feasibility and validity of the suggested approach are demonstrated in case studies with a revised IEEE 33-bus system.