Robust Automatic Voltage Regulation Using Modified Super Twisting Sliding Mode Control

This study proposed the modified super twisting sliding mode controller (Modified ST-SMC) for controlling the automatic voltage regulation (AVR) system and compared it with different existing sliding mode controllers. The particle swarm optimization (PSO) metaheuristic algorithm is used to optimize the controllers. Integral time absolute error (ITAE) is considered as the objective function of the algorithms. SMC performance is assessed with and without disturbance signals. Signum reaching law, power rate reaching law, and super twisting-based SMC showed inferior performance to the modified ST-SMC. It achieved the lowest rise time (0.0252 seconds), settling time (0.0717 seconds), and peak value (1.1333). Considering disturbance, the gain margin and phase margin of the modified ST controller-based SMC system are infinite and 39.8 degrees, which illustrates the system is stable under disturbance.