Power sharing among multiple solar photovoltaic (PV) systems in a radial distribution feeder

Abstract

With an increasing penetration of solar photovoltaic (PV) systems, power distribution grids are becoming more susceptible to network voltage rise. As per applicable standards for grid-integrated PV systems, a PV system must be automatically disconnected from the grid when the terminal voltage of the PV system exceeds a defined maximum voltage. With this directive, in certain situations, PV systems connected at nodes at which the voltage sensitivity is high, may be disconnected from the grid while PV systems connected at less sensitive nodes are continuing to operate. In such a situation, owners whose PV systems are connected at nodes at which the voltage sensitivity is high, may loose their revenue. In order to minimise such a disadvantage, the current research proposes a power sharing methodology for PV systems that are connected to a radial distribution feeder by allocating a grid voltage bandwidth for each PV system to operate. The proposed method enables equal power sharing among multiple PV systems in situations where disconnection of PV systems may be necessary due to the presence of high voltages in the grid in the absence of such a power sharing methodology. Simulation results presented in this paper verifies the validity of the developed methodology.