Control strategies for residential battery energy storage systems coupled with PV systems

This paper presents, and compares the performances of four control strategies for residential battery energy storages coupled with photovoltaic (PV) energy systems. The control strategies are: 1) rule based control, 2) optimization based control without utility constraints, 3) optimization based control with utility constraints, and 4) distributed control. The first two methods only concern about fulfilling the battery owner's requirements. In the other two methods, the utility is involved in controlling the operation of the batteries into certain extent. Therefore, the batteries intentionally contribute to lower the overvoltage risks while fulfilling the customers' needs. From the simulations it is shown that a significant reduction in reactive power support required from the converters can be achieved with optimization based control with utility constraints and distributed control schemes. Distributed control scheme shows best performance in terms of reduction in reactive power requirement, reduction in line losses and decreasing voltage unbalance. All these can be realized with little impact on the battery owner's desired objectives.