A Hybrid PSO-GWO Fuzzy Logic Controller with a New Fuzzy Tuner

A hybrid PSO-GWO PID-type fuzzy logic controller (FLC) with a new online fuzzy tuner is proposed in this study to control a second-order system with varying parameters. Initially, the output scaling factors and the universe of discourse of membership functions for the PID-type FLC are optimized employing a hybrid particle swarm optimization (PSO) and grey wolf optimization (GWO) technique. The superiority of the hybrid PSO-GWO has been demonstrated by comparing with other methods, namely PSO, GWO, and hybrid CS (cuckoo search)-GWO. Additionally, a new online fuzzy tuner structure is proposed by tuning a single output scaling factor to overcome the major disadvantages of the previous approach using the relative rate observer and fuzzy parameter regulator (RRO-FPR). Simulation results show that all the given optimal PID-type FLCs with the proposed new fuzzy tuner produce a better system performance and exhibit a shorter settling time/rise time than the RRO-FPR approach. The proposed optimal PID-type FLC with a fuzzy tuner, which is optimized by the hybrid PSO-GWO method, proves to be superior to others given in this study by exhibiting the shortest settling time/rise time and the lowest overshoot in a practical application to the speed control of a nonlinear DC motor system. Therefore, utilization of the proposed, improved controller to nonlinear systems in dealing with dead-zone and unexpected disturbance is highly feasible.

Automated summary

A hybrid PSO-GWO PID-type fuzzy logic controller with a new online fuzzy tuner is proposed for controlling a second-order system with varying parameters. The controller optimization is achieved by a hybrid PSO-GWO technique, which outperforms other methods (PSO, GWO, hybrid CS-GWO). The proposed controller shows superior system performance, shorter settling time/rise time, and better disturbance rejection in practical applications, making it highly feasible for nonlinear systems.