Modern Trends in Power System Protection for Distribution Grid with High DER Penetration

Increasing renewable penetration and grid modernization initiatives are having a significant impact on the operating and fault characteristics of distribution systems. As a result, protection systems need to account for the changing nuances in systems transient response to disturbances and the resulting voltage and/or current to ensure safe and reliable operation. The approaches for modeling and analyzing power systems also need to evolve accordingly, based on the choice of protection system. Therefore, this paper reviews the state-of-the-art and evolving approaches for the protection of future energy systems. The approaches are categorized based on operating principles and variations in the underlying mathematical formulation – to present a comprehensive overview on fault detection and recommendations for future research. The evolving nature of distribution systems, interconnection requirements and standards, and system automation is also discussed in view of the need for higher fidelity models and/or limitations from current approaches. Finally, the protection algorhithms are compared based on their associated challenges with reliability, protection, and communication/design needs.