Angle stability improvement using optimized proportional integral derivative with filter controller

Abstract

Low-frequency oscillations in large power systems may result in system instability under large disturbances. Proper implementation of damping devices is required to dampen oscillations and thus maintain or improve the stability of the power system. Distinct scheme modeling approaches have been used for dampings, such as power system stabilizers, flexible alternating current transmission systems (FACTS), and coordination control. FACTS are commonly used to damp inter-area modes of oscillations. The damping performance of FACTS devices depends on the design of their controllers. The robust design of FACTS controllers requires a suitable objective function and optimization technique to optimize its parameters. Objective function with various formulations has a significant role the in the design of robust damping controllers in power systems. The comparative performance of the objective function application is a critical task in controller design. Its main purpose is to relocate the eigenvalues of a system unstable region into a stable region. This research aims to develop a thyristor-controlled series compensator (TCSC) equipped with a proportional integral derivative with filter (PIDF) controller using a new optimization technique called evolutionary programming sine cosine algorithm (EPSCA) with multi-objective (MO) function. EPSCA is developed by merging evolutionary programming (EP) and sine cosine algorithm (SCA). Meanwhile, the MO function is a combination of three stability indicators: damping ratio, damping factor, and eigenvalues at a certain ratio. EPSCA is designed to optimize TCSC PIDF controller parameters to obtain an optimal solution with a new MO function as an objective function. The TCSC PIDF controller using EPSCA based on MO function was compared with TCSC proportional integral derivative (PID) controller and proportional-integral (PI) controllers. All simulations were accomplished using a linearized mathematical model of the TCSC SMIB system. EPSCA was examined on a single machine infinite bus (SMIB) system under distinct loading situations and compared with three standardized methods, which are SCA, moth flame optimization technique (MFO), and EP. In addition, the TCSC PIDF controller using EPSCA based on MO function was compared with other indicators such as damping ratio (DR) and damping factor (DF) as the objective function. The dynamic performance was validated concerning the damping factor, damping ratio, the eigenvalue’s location in the s-plane, and rotor angle deviation response to demonstrate system stability. MOEPSCA- based PIDF damping controller showed substantial improvements in settling times (7 s) and overshoot (9.4 %) as compared to DR-EPSCA, DF-EPSCA, and PIDFU. MO-EPSCA-based PIDF damping controller showed substantial improvements in settling times (7 s) and overshoot (9.375 %) as compared to TCSC-PID, TCSC-PI, PIDF-U. The EPSCA design design-based damping controller showed significant improvements in settling times (7 s) and overshoot (9.37 %) as compared with SCA, MFO, and EP techniques and un-optimized PIDF-U system. The results showed that the EPSCA based on MO is more effective than the other techniques to tune TCSC PIDF controller parameters and enhance the power system stability by damping oscillations. The suggested method of optimization, which combines a new multiobjective function and damping controller model, validates the robustness of the damping controller's design for the SMIB system and shows that it can be applied to large, interconnected power systems.