Optimal voltage control using inverters interfaced with PV systems considering forecast error in a distribution system

In recent years, distributed generation (DG) and renewable energy sources (RESs) have been attracting special attention in distribution systems. RESs such as photovoltaic (PV) systems are used as a source of green energy. However, a large amount of DGs causes voltage deviations beyond the statutory range in the distribution systems. This paper proposes a methodology for voltage control using the PV interfaced inverters and tap changing transformers. The proposed method uses a one-day schedule of voltage references for the control devices, which is determined by an optimization technique based on the forecast values of load demand and PV power generation. However, since the forecast value includes a forecast error, there is a possibility that the voltage control performance is affected. Thus, this paper introduces a replanning of the control reference schedule in order to reduce the forecast error impact on the control performance and its objectives.