A Single‐Switch Misalignment‐Tolerant LCC‐LCC Compensated WPT System With Inherent Constant Current and Constant Voltage Outputs

ABSTRACT Wireless power transfer (WPT) charger with constant current (CC) output and constant voltage (CV) output has gained significant attention in battery charging applications. The coil misalignment and wide load resistance range present challenges to the design and control of WPT charger. A single‐switch LCC‐LCC compensated WPT system with inherent CC output and CV output is proposed in this paper. In the proposed WPT system, only one switch is used, which reduces the number of switches and the corresponding driver circuits. The shoot‐through risk in the half/full‐bridge inverter can be avoided. The asymmetric coil structure is adopted to smooth the variations of the coupling coefficient of the loosely coupled transformer (LCT), which improves the system's misalignment tolerance. In addition, the transition from CC output to CV output is automatically completed according to the load conditions, which eliminates battery state detection and control strategy. The proposed WPT system has advantages of low cost, low complexity, high reliability, and wide zero voltage switching (ZVS) and misalignment tolerance range. A laboratory prototype with 3‐A output current in CC mode and 72‐V output voltage in CV mode is constructed to verify the analysis. The experimental results show that the system can achieve the required inherent CC and CV outputs when the misalignment distance in the horizontal direction is within 70 mm, and the peak efficiency of 90.9% is realized.