Design of Misalignment-Insensitive Inductive Power Transfer via Interoperable Coil Module and Dynamic Power Control

Abstract

This article proposes a misalignment-insensitive inductive power transfer (IPT) via interoperable tricoil module and dynamic power control. Since the misaligned coils is known to affect the power transmission efficiency and coupling performance, the article is devoted to the design of an interoperable tricoil module along with power modulation technique in the anticipation of reaching the misalignment-insensitive IPT. In this circuit design, three half-bridge inverters are deployed to drive three transmitting coils. Both geometric structure and magnetic field of coil modules are assessed. A dynamic power control strategy is implemented to adjust the amount of transferable power following the determination of the direction of movement of receiving coils, ensuring a higher efficiency of power transfer and coupling balance at the time of misalignment. To validate the practicality of this approach, the hardware prototype of tricoil module with IPT capability of 3.2-kW is realized with a 7% improvement of efficiency at a misalignment of 100 mm. These results support the feasibility of the proposed approach, serving as beneficial references for automatic guided vehicle applications.