Review and evaluation of control-based protection solutions for converter-dominated power systems

With the rapid and massive increase of converter-interfaced resources (e.g. renewable generation, HVDC systems, etc.), the dynamic behavior of future power systems is expected to change significantly and will be predominantly determined by converters' control strategies. As a result, the performance of conventional protection schemes can be severely compromised due to the new and different fault characteristics introduced by converters. Recent studies reveal that, converter control could be designed in a manner, e.g. to intentionally inject certain fault signature or sequence components, that can effectively facilitate the protection operation, offering a promising solution to address the aforementioned protection challenges. While the control-based protection solutions have increasingly been investigated by the research community, there is no comprehensive comparison and evaluation of different proposed approaches. Therefore, this paper presents a comprehensive state-of-the-art review and evaluation of converter control-based solutions for addressing protection challenges, which covers approaches based on active signal injections, symmetrical component control, and integrated control and protection. Case studies of selected control-based solutions are presented, where the virtual impedance-based Grid-Forming (GFM) control is compared with dual-sequence current-based Grid-Following (GFL) control for distance protection, and it was found that GFM control can more effectively support the distance protection operation.