Constant Power Control of LCC-LCC Compensated Wireless Charging Systems Based on Sensitivity Analysis

Wireless charging systems for electric vehicles (EVs) are increasingly adopting LCC-LCC compensation networks due to their superior performance in terms of power transfer efficiency and stability. However, similar to other compensation networks, the LCC-LCC compensation network also faces the challenge of its output performance being highly sensitive to variations in the coil coupling coefficient. Furthermore, this topology incorporates a relatively large number of compensation components, and parameter deviations in different components exhibit varying degrees of influence on the system's output characteristics. This paper presents a comprehensive sensitivity analysis of the LCC-LCC compensation network to identify the most influential parameter on the system's output power. By leveraging this parameter, we propose a novel control strategy using a switch-controlled capacitor to maintain constant power output despite variations in the coil coupling coefficient. Theoretical analysis and simulation results demonstrate the effectiveness of the proposed method in achieving stable power transfer.