A Novel Impedance Compensation Method for IPT System Applying Inverse Coupled Current Doubler Rectifier

Inverse coupled current doubler rectifier (ICCDR) has been applied in high output current scenarios due to its higher current gain and rectification efficiency than diode full-bridge rectifier. However, existing analysis about ICCDR has nonnegligible errors because the inductance effect of a transformer is simply ignored. In this letter, the inductance effect and energy storage-release process of transformer are taken into account innovatively. Then, an accurate input impedance model of ICCDR is first established via modal analysis, whose equivalent inductor leads to poor constant current effect within large load range. Based on this input impedance model, a novel compensation method, which can eliminate the impact of its equivalent inductor and optimize constant current output effect by tuning primary capacitance, is provided. The proposed S-S compensated inductive power transfer system applying ICCDR achieves zero phase angle and shows a ±5% output current change rate within 8:1 load resistance range. The analysis is verified by a 20-A output prototype, which shows a peak efficiency of 95.6%.