A decentralized voltage regulation method in low-voltage feeders with PV systems and domestic loads

A decentralized control method for photovoltaic (PV) inverters in low-voltage feeders with domestic loads and PV systems is proposed, with which the voltage profile along the feeder is kept within the limits specified by the EN 50160 standard and the branch currents in the feeder are kept below the thermal limit at all possible operating conditions of the load, the PV generation or the voltage fluctuations in the Medium Voltage network. Each PV inverter should adjust its reactive power according to a precalculated reference voltage, which is set just once before each inverter´s installation. The reference voltage can be calculated by a simplified analytical method, the accuracy of which was tested against detailed simulation models. This method is also used to calculate the PV penetration level under certain constraints regarding the installed PV power per node, the kVA rating of the inverters and the operation during the night.