Fault ride through capability and voltage support in distribution grid with photovoltaic distributed generation

When connected to the power distribution grid, Distributed Generation Photovoltaic (DGPV) systems not only contribute to supply the load demand, but can also assist the grid performance by means of several ancillary services, notably in voltage support after a voltage drop. Main current grid codes and international standards require DGPV units to remain connected even in the event of severe voltage sag. In order to minimize the impacts on the distribution grid, the photovoltaic sources can be used to inject reactive power. This paper discusses the main aspects related to voltage support using DGPV sources and proposes a voltage control architecture, considering the contribution of each DGPV unit and using a distributed communication infrastructure.