Optimal Robust PID-PSS Design for Melioration of Power System Stability Using Search and Rescue Algorithm

The larger share of renewable energy power generation in the energy sector increases the system uncertainty and worsens the dynamic behavior. Although the Power System Stabilizers (PSS) can accomplish the dynamic torque, the proper tuning of parameters is essential in preserving the system stability. In this research work, large variations in system operating conditions due to unpredictable circumstances are modeled using transfer function with interval coefficients, and simple stability constraints are developed from it to ensure system stability. The performance of a Single Machine Infinite Bus power system is enhanced by defining a Multi-Objective Function (MOF), to minimize the variations in the Proportional-Integral-Derivative (PID)—PSS parameters with respect to nominal loading condition and to meet the practical conditions. The Search and Rescue optimization algorithm is used to tune the parameters of the proposed PID-PSS controller by minimizing the MOF while satisfying the developed stability constraints. The effective performance of the proposed PID-PSS controller is illustrated by comparing it with the significant controllers available in the literature, under a wide range of operating conditions when exposed to a step mechanical disturbance.