Enhancement the Frequency Stability and Protection of Interconnected Microgrid Systems Using Advanced Hybrid Fractional Order Controller

Abstract

Substituting conventional energy sources with new renewable sources is crucial issue nowadays in energy generation systems to face climate changes and increased load demands. Due to the increased penetration levels of renewable sources in power systems, the benefits of the high-inertia of conventional sources are being insufficient. The resulting low-inertia power systems introduce several stability, reliability, and coordination problems for power system operation and control. Therefore, this paper tackles the coordination assessment and enhancement between digital frequency relays using a new fractional order load frequency controller equipped with superconducting magnetic energy storage (SMES) virtual inertia system. The improved coordination method is established using optimized fractional order controller based on slime mould optimization algorithm (SMA). The proposed SMA-based design method benefits the adaptive weights of SMA algorithm. The proposed design is generalized to be applied on single area and multi-area interconnected power systems as well. Compared to existing literature, this paper presents an advanced fractional order controller with coordinated operation with existing protection relays. The obtained results show the coordination shortcomings of renewable energy based microgrids with traditional control systems. However, improved design and coordination are obtained using the proposed SMA-optimized fractional order controllers. The superiority and feasibility of the proposed analysis and methods are verified on different case studies using single and multiple interconnected areas.