New variable structure control based on different meta-heuristics algorithms for frequency regulation considering nonlinearities effects

In the electrical grids, the main target of the controller design is represented in the decreasing of the settling time and the overshoot of frequency deviations. The optimization of the controller gains represents the main challenge that affects the controller performance. Many intelligence techniques are used for the tuning of the controller gains such as the genetic algorithm (GA) and the bacterial foraging optimization algorithm (BFOA). These algorithms may have some drawbacks when the complexity of the system increases. These drawbacks may be due to the design method of the gain selection of the proportional-integral (PI) controller. The design method may characterize the PI controller to reduce the maximum overshoot of the system response but the settling time increases. On the contrary, another different design method may characterize the PI controller to reduce the settling time of the system response but the maximum overshoot increases. This paper suggests a new variable structure gain scheduling (VSGS) for frequency regulation. The VSGS can take advantage of the BFOA-based PI controller, which is the minimization of settling time, and the advantage of the GA-based PI controller, which is the minimization of overshoot. The performance of the proposed method is compared with the performance of the GA-based PI controller and the BFOA-based PI controller.