Comparative analysis of sliding mode and terminal sliding mode current control for Direct-Drive wave energy converters

Given the current interest in increasing the world’s reliance on clean energy, wave energy systems, more specifically direct drive wave energy systems have been proposed as an alternative for non-renewable energy sources. However, issues like current ripples, which can impair the stability and effectiveness of the energy conversion process and sluggish response time, which leads to uncertainties and unreliable output of electrical power, have prevented them from reaching their fullest potential. This study recommends the implementation of sliding mode as a current controller in direct drive wave energy systems. Sliding mode control is known for its reliability in coping with system uncertainties and disturbances. By employing sliding mode control, we aim to regulate the current within the system precisely, thereby reducing current ripples and improving the overall energy conversion yield. Moreover, this article also promotes terminal sliding mode control as a better and more reliable alternative to conventional sliding mode controllers. Terminal sliding mode control expands the capabilities of sliding mode control, thereby achieving faster and more accurate control performance. These advanced control methods can cut current ripples by more than 50%, while maintaining optimal operating conditions.