Enhanced fault protection coordination in wind-solar distribution grids utilizing improved hyper spherical search based optimization.

The incorporation of renewable energy sources (RES) into distribution networks presents considerable hurdles for protective relay coordination due to variable fault currents and swiftly altering operational conditions. This paper introduces an Improved Hyper Spherical Search Algorithm (IHSSA) designed for optimal relay coordination in renewable energy source-integrated power systems. The IHSSA improves the conventional hyperspherical search method by integrating dynamic adjustment mechanisms that adaptively balance exploration and exploitation, facilitating quicker convergence and more accuracy in addressing intricate, high-dimensional optimization challenges. The algorithm's efficacy was assessed using a realistic 220/6.6 kV substation model that services a hybrid wind-solar distribution grid with 10 feeders and 5 renewable generators. Simulation results indicate that IHSSA surpasses benchmark methods, including Particle Swarm Optimization (PSO) and Genetic Algorithm (GA), delivering an 18% decrease in relay operation time and a 15% enhancement in coordination margin under extreme fault situations. The method also decreased fault clearing settling time to 120 ms, demonstrating enhanced adaptation to renewable intermittency. The IHSSA architecture was executed in a real-time hardware-in-the-loop (HIL) setting utilizing OPAL-RT OP5600 connected to IEC 61,850-compatible relays to assess practical viability. The findings validate that IHSSA provides a strong, adaptive, and scalable solution for protection coordination in contemporary, renewable-dominant distribution systems, markedly improving system dependability and operational resilience.