Optimized Event-Based Sliding Mode Control of OWC Wave Energy System

This paper deals with optimized event-based sliding mode control (SMC) of oscillating water column (OWC) wave energy system. The objective of event-based controller is to lower the number of control updates while the controller communicates with OWC via a communication link. It helps in efficient utilization of communication resources. Firstly, the conventional SMC is designed for rotor speed regulation using Lyapunov stability analysis. Then, an event triggering criterion has been designed by guaranteeing the asymptotic stability of the closed loop system. The parameters of event-based SMC (E-SMC) are further optimized to fine tune the controller performance. It is implemented using integral-time-absolute-error (ITAE) form of fitness function, which is minimized using different optimization techniques. Finally, the simulations are performed for closed loop OWC system. The performance of optimized event-based SMC (OE-SMC) is compared with E-SMC in terms of ITAE and OWC rotor speed. Also, an analysis of fixed sampling SMC (FS-SMC) and OE-SMC has been conducted to feature the merits of the recommended control method.