Using power factor to limit the impact of energy storage on distribution network voltage

The introduction of embedded renewable generation and energy storage into the electricity grid may result in increased complexity to the Distribution Network Operator (DNO) in managing the voltage within statutory limits. This paper investigates how the voltage at the point of common coupling between the grid and an energy storage system could be adapted such that the charging and discharging of a battery energy storage system has a neutral impact on the voltage at that point. The paper uses measured results from the Willenhall Energy Storage System to show that a “seagull” shape curve of Power and corresponding Var setting could be used to mitigate against voltage rise or fall on the Network caused by the Energy Storage System.