Distributed energy storage for mitigation of voltage-rise impact caused by rooftop solar PV

A high penetration of solar photovoltaic (PV) resources into distribution networks may create voltage rise problem when the generation from PV resources substantially exceeds the load demand. To reduce the voltage rise, the excess amount of power from the solar PV units needs to be reduced. In this paper, distributed storage systems are proposed for the mitigation of voltage rise problem. The surplus energy from the solar PV is used to charge the distributed storage units during midday, when the power from the solar PV would be typically higher than the load level. This stored energy is then used to reduce the peak load in the evening. An intelligent strategy for charging and discharging control to make effective use of the storage capacity is discussed. The proposed voltage rise mitigation strategy is verified on a practical low voltage distribution feeder in Australia.