Performance Analysis of a Low Voltage Distribution Network in Pakistan under High Penetration of Rooftop Solar PV Systems

This paper investigates the technical problems which may arise when three-phase and single-phase residential rooftop solar PV systems are integrated into a low voltage (LV) distribution feeder. The study incorporates real data to simulate the actual behavior of a distribution feeder of Lahore Electric Supply Company (LESCO), a distributed network service provider (DNSP) in Pakistan. Voltage variations, system loading, and losses were noted for different degrees of PV penetration to test the boundary of system security and safe operational performance. The test system has been modeled in Synergi Electric software for this study. The work in this paper is prompted by the fact that very limited study has been done on rooftop solar PV integration into a weak LV network subjected to poor voltage profile and high loss. It is noted that the voltage profile of the system improves when PV penetration is within the range of 5% to 50%, and the losses are also reduced. Hence, careful utilization of solar PV technology can help improve system voltage and reduce the losses of a weak distribution system.