Protection Systems for Modern Converter-Dominated Power Networks: A Comprehensive Analysis of Challenges and Solutions

Abstract

The present power system landscape is transitioning towards a dramatic shift due to the unprecedented penetration of renewable energy sources, complementary Energy Storage (ES) systems, and Power Electronic Converters. This shift has profoundly affected contemporary power networks' operational behavior and security needs, where the conventional synchronous generator-based systems are moving towards converter-dominated infrastructures. Traditional protection methods, which were carefully engineered and tuned to serve networks controlled by synchronous machines, now have many operational difficulties in environments with pervasive use of converters. Such difficulties mainly arise from the inherently distinct fault response behavior of power electronic converters; they have much lower fault current contributions, time-varying dynamic impedances, and their control-induced dynamics lack predictability as opposed to traditional mechanical rotating machines. In this work, a thorough review is performed to systematically investigate the varied protection issues faced by conventional power networks penetrated with converters. It comprehensively evaluates the state-of-the-art technological solutions being developed to deal with these challenges. Analyses include adaptive protection schemes that adjust to dynamic system conditions, wide-area protection systems using synchronized measurements over several network locations, and advanced communication-assisted approaches supporting coherent protection actions. This effort provides comprehensive state-of-the-art analyses of present trends in research, along with the key technical gaps that need to be closed to enable practical, affordable, and reliable protection solutions for the fast-growing 21st-century power grid infrastructure.