Control Scheme for Phase Balancing and Reactive Power Support from Photovoltaic Inverters

The massive integration of intermitted renewable energy sources and the electrification of the transportation sector (e.g., electric vehicles) impose substantial challenges for the distribution system operators. These challenges include possible deterioration of the power quality, efficiency and stability of distribution grids. Therefore, the provision of ancillary services in a coordinated way is vital to alleviate these challenges, especially under high penetration of photovoltaics. This paper proposes a centralized control scheme for coordinating phase balancing and reactive power support services at the substation level of a distribution feeder. The distribution feeder controller is adaptively regulating the provision of phase balancing and reactive power support according to the loading conditions at the substation level. The proposed method is shown to provide significant benefits for the low voltage distribution grid in terms of power quality, stability, reduced energy losses and utilization of the network capacity.