On-line adjustment of battery schedules for supporting LV distribution network operation

Abstract

Increasing domestic demand for electric energy is expected to put significant strain on the existing power distribution networks. In order to delay or prevent costly network reinforcement, some UK Distribution Network Operators (DNOs) are investigating the use of Battery Energy Storage Solutions (BESS), or other demand response systems, in the Low-Voltage (LV) power distribution networks to reduce peak demand. In most cases the control strategies, and metrics of success, are evaluated on a half-hourly basis and so sub-half-hourly (i.e. minute by minute) variations in demand are not effectively addressed. In this work, a closed-loop optimisation methodology is proposed that adjusts the pre-scheduled charging profile of a BESS in a sub-half-hourly manner in order to improve network operation whilst maintain the same average net energy flow over the half-hour period. This new approach guarantees that the BESS follows its predetermined half-hourly schedule, yet voltage and power imbalance, network losses, and feeder overloading are additionally mitigated through sub-half-hourly control actions. For validation, this paper presents a case study based on the real BESS installed in Bracknell as part of Thames Valley Vision project with Scottish and Southern Energy Power Distribution (SSE-PD) evaluated on the IEEE LV test case feeder model.