Capacitive Power Transfer With Series-Parallel Compensation for Step-Up Voltage Output

In this paper, a basic capacitive power transfer (CPT) topology with series-parallel (SP) compensation is developed for load-independent step-up voltage output. There are three main contributions. First, the step-up constant-voltage (CV) output and zero-phase angle (ZPA) property are designed by using an h-parameter modeling method. Second, a current-source rectifier (CSR) is proposed at the secondary side and the working transient is analyzed. Third, the impact of parasitic resistances is investigated, and the output voltage attenuation and system efficiency are analyzed at different loads, coupling coefficients, and quality factors. A 130 W prototype is implemented with 150300mm metal plates. Experiments validate the CV output property with a step-up voltage gain of 2. The peak efficiency is 86.6% at a coupling coefficient of 0.16 and a transfer distance of 4mm.