Power System Voltage Stability Assessment and Control Strategies: State‐of‐the‐Art Review
Yalew Gebru Werkie, George N. Nyakoe, Cyrus Wabuge Wekesa
Abstract
Voltage stability is crucial for power systems, ensuring that electrical grids maintain voltages within acceptable limits with increasing demand, renewable energy integration, and changing network topology. This paper reviews the voltage stability phenomena, voltage stability indices (VSIs) (line and bus), and offline/online voltage stability assessment considering load variations, uncertain renewable energy, and network structures. Multiple VSIs and algorithms quantify voltage stability, providing information on the system’s resilience to disruptions. A systematic review encompassing the essential aspects of mathematical formulation, expressions, constraints, and applicability of VSIs is presented. Also discussed is the voltage stability control strategy employing flexible AC transmission system (FACTS) devices, considering the incorporation of the power generated from renewable resources. A comparison of voltage stability analysis methodologies is performed. The study offers power system researchers and practitioners a comprehensive summary of voltage stability assessment methods and control strategies for integrating various FACTS devices with renewable energy sources. Finally, the challenges and limitations of voltage stability assessment and control are discussed, as are further research directions.