Impact of High Photovoltaic Penetration on the Voltage Stability of Vietnam's Power System

Photovoltaics (PV) play an essential role in energy networks by promoting clean, sustainable energy and reducing reliance on fossil fuels. However, their operational characteristics introduce new challenges, particularly concerning grid reliability and voltage stability. In this paper, the impact of solar photovoltaic plant (SPP) penetration on voltage behavior in the central region of Vietnam is examined using dynamic models at different integration levels, ranging from 0% to 40%. The results reveal that while low SPP penetration has minimal effects, high penetration levels (30% and 40%) significantly reduce reactive power support, exacerbating voltage collapse risks. These findings underscore the necessity for advanced voltage and reactive power control strategies to ensure grid stability in high-SPP scenarios.