An Integrated Mutually Compensatory Dual Receiver for AGV Misalignment-Tolerant IPT Charging

Abstract

The inevitable misalignment of magnetic couplers presents a substantial challenge to the power transmission and efficiency of inductive power transfer (IPT) systems. In this brief, an integrated mutually compensated dual receiver (IMCDR) IPT system for automated guided vehicles with high-efficiency constant current (CC) charging over a large misalignment tolerance (MT) range is proposed. The dual-channel receiver comprises two solenoid coils perpendicularly wound to each other to capture the magnetic flux along the y- and z-axes generated by the transmitter. In this way, two mutual inductances with opposite changing trends are utilized to synthesize an equivalent mutual inductance $(M_{\mathrm { eq}})$ over an MT range. Further, the proposed IMCDR structure was optimized using the finite element method to obtain the optimal receiver length and $M_{\mathrm { eq}}$ fluctuation rate. Finally, a 535-W/85-kHz experimental prototype was conducted. Experimental results showed that the proposed IPT system can maintain the output current fluctuation rate within 5.82% with fixed duty/frequency condition when operating over a 172% MT range, and the system efficiency ranges from 88.42% to 90.67%.