A novel adaptive Gaussian FOPID controller design for automatic voltage regulator system

The fundamental aim of a power system is to deliver electricity to consumers in a secure, continuous, and reliable manner. Achieving this goal requires maintaining the overall stability of the power system. Stability is a multifaceted concept that encompasses components such as voltage, frequency, and rotor angle; this study focuses on voltage stability. Within synchronous generators, automatic voltage regulator (AVR) systems are essential for sustaining voltage stability. To improve the dynamic performance and robustness of the AVR system, this study proposes a new control method called Gaussian-based fractional-order PID (GFOPID) controller. The controller parameters for the proposed GFOPID structure are optimized using the Jellyfish Search (JS) optimization algorithm. In the optimization phase, we employed several well-known error metrics as performance criteria: the integral of absolute error, the integral of squared error, the time-weighted integral of absolute error, the time-weighted integral of squared error, and the user-defined Zwe Lee Gain (ZLG) objective function. The performance of the JS-GFOPID controller in the AVR system was assessed through analyses of time-domain response, robustness, reference signal change, disturbance rejection, and nonlinear effects. The GFOPID controller was compared with fractional-order PID (FOPID) controllers, which have gained considerable acceptance in recent years when used with different metaheuristic algorithms. Under reference-changing inputs, the proposed GFOPID/ITAE controller provides between 25–73% improvement in IAE, 2–63% in ISE, and 21–57% in ITAE when compared with benchmark FOPID-based strategies.