Coordinated Design of Power System Stabilizer and Virtual Inertia Control Using Modified Harris Hawk Optimization for Improving Power System Stability

In the current era, power system stability faces typical problems due to the Renewable Energy Sources (RES) integration trend. This trend makes the coordination between power system controllers crucial to maintain stability across a wide-range of operating behaviors. To address this problem, this paper proposes the coordinated design of Power System Stabilizer and Virtual Inertia Control (PSS-VIC) to improve the stability of the power system integrated with RES. The proposed method uses the modified version of Harris Hawk Optimization with Memory Saving Strategy (HHO-MSS) to find the equilibrium point of global parameters of PSS-VIC through various simulations to ensure scalability. In this proposed method, PSS is focused on increasing the power system stability from the traditional generator sides with diesel engines, thermal, and hydro turbines. Meanwhile, the modified VIC design is proposed to increase the power system stability from the RES sides using virtual inertia emulation with the integration of wind generators, solar photovoltaic units, and energy storage systems. The global parameters of PSS-VIC are determined by calculating the optimal damping ratio which is permitted by grid codes alongside various stability criteria validation. Based on the obtained results, HHO-MSS is 1.44% to 9.28% more accurate and 34.63% to 53.94% more consistent than Electric Eel Foraging Optimization (EEFO), and Puma Optimizer (PO), Evolutionary Mating Algorithm (EMA). With the optimal damping ratios of 9.94% to 9.96% achieved by HHO-MSS, the overall power system stability improvements, including both local and interarea responses across 38 simulations involving sudden load changes, varying inertia, and different RES levels, are as follows: 41.17% to 70.89% frequency nadir improvement, 25.9% to 67.38% power angle deviation improvement, 84.83% to 85.26% settling time reduction, and 51.57% to 89.73% average error reduction calculated with performance indices. The proposed coordinated PSS-VIC design offers excellent scalability and can effectively improve power system stability across a wide-range of operating conditions.