3-D Misalignment Tolerant E-Scooter IPT System With Hybrid Control Based on Three-Coil Design for Load-Independent CC/CV Outputs

This article proposes a hybrid control strategy to address the large-scale 3-D misalignment tolerance (MT) challenges for E-scooter IPT charging systems. The strategy is based on a three-coil loosely coupled transformer (LCT) design that realizes constant current (CC) and constant voltage (CV) outputs. To achieve this, a control method using a novel half-bridge rectifier (HBR) is proposed to realize topology reconfigurability based on DS-LCC and LCC-S topologies with CC and CV output characteristics, respectively. In addition, a magnetics optimization-based design method for adjustable mutual inductance of three-coil structure is proposed to address the horizontal MT. Phase shift control (PSC) is also adopted to solve the vertical MT problem caused by different types of E-scooter and air gap variations caused by tilt angles. Finally, according to a predetermined MT range, a 122.8 W/85 kHz experimental prototype is designed to test the performance of the proposed hybrid control IPT system. Experimental results show that the proposed IPT system is able to control the CC and CV within a 5.5% fluctuation range across MT ranges of 42% and 15% in the horizontal and vertical directions, respectively. Furthermore, high efficiency and zero-voltage switching (ZVS) operation is maintained over a wide range of load variations.