The Design of Fuzzy Logic Controller for Efficiency Improvement of Capacitive Power Transfer System

This study introduces a control strategy to enhance the efficiency of Capacitive Power Transfer (CPT) systems, even when the load varies. Compared to Inductive Power Transfer Systems (IPT), CPT systems are known for being flexible and safe. However, their efficiency is significantly affected by load variations. Therefore, to address this problem, we propose using a Fuzzy Logic Controller (FLC) to adjust the operating frequency of the MOSFET based on Output Current and Output Voltage inputs of the CPT circuit. To be specific, a relationship between load changes and output variations is first established and the If-Then rules is then proposed for the FLC. Through simulations of the Class E CPT system, both with and without the FLC, we demonstrate that the FLC-equipped CPT system maintains 92% efficiency despite a +15% load variation. In contrast, the CPT system without FLC achieves only 48% efficiency under the same conditions. This underscores the FLC’s effectiveness in enhancing CPT system efficiency amidst varying loads.