Impact of Increased PV Penetration on Steady State Voltage Stability

This paper investigates the impact of higher renewable energy penetration, specifically photovoltaic (PV) systems, on future utility-scale or transmission systems. Though the PV system is regarded as a cleaner alternative to fossil fuels, its integration poses challenges due to its uncertainties and the power electronics utilized for interfacing them to the grid, where voltage stability becomes a primary concern. This paper investigates the steady-state voltage stability of the modified version of the IEEE 9-Bus test system with higher levels of photovoltaic integration. The base case is assumed without PV penetration. Other scenarios include 22% to 56 % PV penetration at unity and 0.95 power factor of the PV generators. The results show that the voltage stability margin with the increased levels of PV penetration is one of the main challenges, demonstrated by a lower system capability to handle loading before the system voltage collapses. DIgSILENT Power Factory software is utilized to simulate these scenarios and validate this paper's findings.