GA-optimised nonlinear pseudo-derivative feedback control of a sustainable, high-speed, ultratall building elevator

The aim of this paper was to compare the sustainable control capabilities of a nonlinear pseudo-derivative feedback (NPDF) controller with its conventional equivalent, as well as with a sliding mode control (SMC) system and two proportional–integral–derivative (PID) controller variants. The NPDF controller obtained the best performance, achieving control with recorded annual savings of at least 6730 kWh over the PID and SMC systems; as well as proving to be more energy efficient than its traditional variant. Additionally, the control architecture exhibited superior robustness to the SMC system, successfully maintaining control of every cabin mass, travel distance and travel direction considered. The results were particularly significant due to the similarity of the control scheme with PID control, the most common industrial control system. This would allow for NPDF control to be implemented in existing PID-controlled systems with relative ease.