The mechanism and optimization method of the capacitance team used in double‐sided LCC compensation topology

Abstract

Abstract Double‐sided LCC compensation topology is often used in various wireless charging systems (WCS) as its resonant frequency is independent of coupling coefficient and load condition. However, the transmission performance of the compensated system was found to be very sensitive to the change of the compensation capacitance. This paper attempts to give a capacitance optimization method based on the comprehensive consideration of effects of capacitance. The four compensation capacitors are divided into parallel capacitance team and series capacitance team, and the work mechanism of the compensation capacitance on the output power, efficiency and the terminal voltage of the system are deeply analyzed. Then, the optimization approach based on Bayesian is given. The results are validated by both simulation and experiments of a 3 kW WCS prototype. With the proposed optimization method, the ac–ac efficiency can reach up to 96.3% over an air gap of 150 mm, which shows a 5% improvement. The voltage of each component is kept within a safe range.