An accurate model of SMES for load frequency control in renewable power systems

This study introduces a state-of-the-art model of superconducting magnetic energy storage (SMES) designed to replicate its real-time functionality when utilized for power system frequency support. Unlike conventional SMES models that continuously exchange power with the grid, the proposed model operates in a free-wheeling state during stable periods and activates only during transient disturbances, significantly reducing unnecessary energy cycling. A dynamic current-limiting mechanism, implemented using NAND logic gates, ensures that the SMES coil current remains within safe operating limits, protecting the superconducting state and extending the system lifespan. Therefore, the shortcomings of conventional SMES models used in the literature are thoroughly explored in this study. The proposed SMES model is tested for its ability to support the frequency stability of a microgrid taking into account the high penetration of renewable energy resources. The simulation results performed using MATLAB software prove the viability of the suggested SMES model in supporting the frequency stability of renewable energy systems. A real-time implementation using the RT-BOX platform enhances the depth and reliability of the theoretical analysis. These findings highlight the proposed SMES model as a cost-effective and technically superior solution for frequency stability support of renewable-rich microgrids.