Impacts of the Detuning of Compensation Inductances to the Performance of a Double-Sided LC-Compensated CPT System

Abstract

This paper investigates the detuning of the compensation inductances in a double-sided LC circuit and its impact to the performance of a CPT system. It reveals that the variation of the inductance would result in an asymmetric frequency property, including the magnitude of the output current and output voltage. The impacts can be summarized in two major parts. First, the phase angle of the input current is affected, which relates to the soft-switching condition and the system power transfer efficiency. Second, the output-side current and voltage magnitude can be affected, which determines the output power. A prototype is implemented to validate the theoretical analysis. The plate size is 300mm×150mm, and it can transfer 368.5W power through 4mm glass layer with the efficiency of 91.8%. For the frequency property, the experimental results and the theoretical analysis match well in a wide frequency range. In addition, the experiments show that both the constant current and constant voltage working modes are achieved with a relatively small load regulation ratio.