Power System Voltage Stability of Saudi Arabia Distribution Network as Affected by Large-scale Photovoltaic Power Penetration

Abstract

Abdelaziz Salah Saidi, Lina Alhmoud, Adel Ali Alqahtanid, Osama Ali, Zemie, Muhammad Umar Malik Photovoltaic (PV) systems are becoming more prevalent globally, especially in power distribution networks. However, their intermittent integration into these networks can pose reliability concerns regarding voltage instability. Voltage instability is a significant threat to the secure operation of power systems worldwide. With the rise of grid-connected renewable energy-based generation for economic and environmental reasons, there’s a growing interest in understanding its impact on voltage stability. This study focuses on assessing and analyzing the effect of 300 MW large-scale PV generation on the voltage stability of the power system, utilizing a comprehensive model tailored to a typical Saudi power grid network. Various performance metrics, including static power flow analysis, PV, and Q-V curves, are employed to analyze how PV generators affect power system static voltage stability. The investigation identifies the maximum permissible PV penetration as 462 MW. Under normal conditions, static load-flow analysis reveals that the highest active and reactive power loss occurs at the transmission lines closest to the solar PV bus. Time domain simulations further corroborate these findings. This work emphasizes the significance of voltage/var control capacity in preserving voltage stability, a feature often deficient in PV systems. It points out that regulating the voltage of PV systems could result in over-voltage concerns, potentially leading to sudden voltage collapse, especially with high regional PV penetration. Nevertheless, the integration of 300 MW large-scale PV demonstrates promising results in static analysis, showcasing reductions in system losses and increased maximum loading capacity of transmission lines.