Periodic Event-Triggered Terminal Sliding Mode Speed Control for Networked PMSM System: A GA-Optimized Extended State Observer Approach

This article proposes a novel periodic event-triggered terminal sliding mode speed regulation scheme for the networked permanent-magnet synchronous motor (PMSM). The novel speed regulation strategy combines advantages of both terminal sliding mode control (TSMC) and periodic event-triggered mechanism. The satisfied speed regulation performance can be guaranteed by using TSMC to compensate the external disturbances and parameter uncertainties. The communication burden between the central controller and the remote motor is reduced by the periodic event-triggered protocol. To reduce the chattering in the TSMC signal, an extended state observer (ESO) is further introduced to estimate all possible perturbations, in which the upper bound of the estimation error is analyzed explicitly. Then, a binary-based genetic algorithm (GA) is adopted to find the optimal observer parameters. A key challenge here is how to estimate the actual bound of the triggering error under the periodic event-triggered mechanism. To this end, an explicit selection criterion of the periodic sampling period is developed by utilizing the known constrained information of the PMSM. It is proven that the proposed novel periodic event-triggered TSMC with a proper selection of the control gain can guarantee the reachability of the sliding region and the ultimate boundedness of the regulation errors simultaneously. Finally, the effectiveness of the proposed novel periodic event-triggered TSMC via a GA-optimized ESO is demonstrated in both simulation and experiment results for a real PMSM platform.