A Magnetic Field Concentration Enhanced I-Shaped Transmitter for DWPT System to Achieve Low Power Fluctuation

Dynamic wireless power transfer is a promising candidate to alleviate the problem of range anxiety and carrying on heavy large-capacity batteries for automatic guided vehicles. In this article, the explanations that the unsymmetrical coupling structures have better performance in the misalignment conditions than the traditional planar couplers are given. Besides, based on the theory of demagnetizing field, an optimized I-shaped structure with a more concentrated magnetic field is presented to consist transmitter array in the dynamic charging system, which has a lower usage of the ferrite and wire and a low output fluctuation during the moving process. A 1.1 kW laboratory prototype is built to verify the feasibility of the proposed system. Experimental results show the system achieves constant output current when the load varies. With single-segment (dual-segment), the output voltage variation is only ±1.03% (±1.18%), and efficiency ranges from 87.22% to 87.98%.