Efficiency Improvement of Class E Capacitive Power Transfer System Using State Feedback Controller

Abstract

This paper addresses the enhancement of efficiency in Class E Capacitive Power Transfer (CPT) systems by using a state feedback controller. Efficient operation is a critical concern in CPT systems due to their sensitivity to parameter variations, notably changes in coupling capacitance and load conditions. Variations in these parameters can substantially reduce the overall system efficiency. Therefore, this paper aims to develop a state feedback controller that can bolster system efficiency even in the presence of parameter variations. To be specific, this study begins by modelling the Class E CPT system using a combination of Generalized State-Space Averaging (GSSA) and Frequency-Domain Harmonic Analysis (FHA) techniques. Subsequently, a Lyapunov function is employed to devise the state feedback controller. The problem is then formulated using Linear Matrix Inequalities (LMIs) and tackled through the utilization of Yalmip. The efficacy of the proposed solution is validated through simulation work. The simulation results demonstrate that the proposed controller is capable of maintaining the CPT system’s output efficiency at a level exceeding 98%, even when subjected to a maximum of 30% variation in load conditions.