Fig. 16

Convergence behavior of the ITAE during controller optimization in Case Study No. 3. The curves correspond to: PID–PSO (Purple), PID–GTO (Olive Green), PID–MPA (Light Brown), PIDD²–PSO (Cyan), PIDD²–GTO (Magenta), PIDD²–MPA (Yellow), (FPIDD²+PIDD²)–PSO (Light Green), (FPIDD²+PIDD²)–GTO (Red), and (FPIDD²+PIDD²)–MPA (Blue).