A Constant Current Output Method for Low-Voltage and High-Current DWPT Systems Based on Inverse Coupled Current Doubler Rectifier

Abstract

Dynamic Wireless Power Transfer (DWPT) technique has promising potential in charging Automatic Guided Vehicles (AGVs) used in intelligent warehousing. To ensure charging safety and reduce charging time, constant and high current output is necessary for the batteries of the in-motion AGVs. However, it is a challenge to achieve the desired constant and high current output with frequent power pulsation phenomenon and high equivalent series resistances (ESRs) loss. To address these issues, a dualreceiver DWPT system with the Inverse Coupled Current Doubler Rectifier (ICCDR) is proposed in this work. Based on the dualreceiver, the AGVs can be charged by two power transfer channels, and the ESRs loss can be reduced. Meanwhile, the ICCDR can automatically switch between full-bridge and current doubler modes according to the mutual inductance variations in the adjacent area. Therefore, constant and high current output can be achieved without additional control strategies. An experimental prototype with 48A-24V output is constructed. Experimental results show the output current pulsation is limited within ±5%, and the efficiency remains above 85% during motion.