For lagging power factor = (IR*cosφ + Ixsinφ)/Vr For leading power factor = (IR*cosφ - Ixsinφ)/Vr Zero voltage regulation occurs on leading power factor only.
A grid-interactive photovoltaic (PV) system uses solar energy to generate renewable power that charges batteries for use during power failures and feeds power into the electricity grid. Grid-interactive systems are based on their grid-tied and off-grid counterparts.