Determining reactive power levels necessary to provide optimal feeder line voltage regulation

An increasing adoption of rooftop photovoltaic (PV) generators presents a growing opportunity for the use of their grid-tie inverters to provide reactive power compensation on medium- and low-voltage distribution networks. This paper presents a generalized method based on particle swarm optimization (PSO) for determining how much reactive power is necessary to provide control over the voltage profile of the distribution line for any given operational condition and number of PV connections. The method is tested with data based on the IEEE benchmark 13-bus feeder system and simulations are run in DIgSILENT using the same system to validate the results. A future two-level distributed control architecture is described that will utilize the methods developed in this paper to provide reactive power compensation for voltage control of an entire feeder line without the need for global information sharing.