A comprehensive review of grid support services from solar photovoltaic power plants

In recent years, the global expansion of solar photovoltaic power plants has seen rapid acceleration fueled by technological advancements, substantial cost reductions, and favorable regulatory reforms. Although pivotal to the transition towards sustainable energy sources, the integration of a large number of photovoltaic plants presents unique challenges for the system operator in ensuring grid stability and security. Therefore, it has become increasingly important for these plants to provide adequate grid support services and maintain voltage and frequency stability, similar to conventional generators. In this context, this paper critically analyses the diverse strategies and advanced trends for acquiring grid support services from solar photovoltaic power plants. The relevant procedures are garnered from the literature, which dates back to the earliest reported methods. The review encompasses the analysis of different applications related to active power control for frequency regulation, reactive power control for voltage regulation, and black-start support for system restoration. The paper also examines the existing challenges and delves into the opportunities to transform the interaction of photovoltaic power plants with electricity grids. As solar photovoltaic penetration increases, the role of these grid support services becomes ever more critical, requiring innovative solutions, conducive regulatory frameworks, and a thriving market structure to support the continuously evolving energy landscape.