A Staggered Bipolar Magnetic Coupler for Dynamic Wireless Charging System

Dynamic wireless charging provides a novel solution for extending the range of electric vehicles, but requires stable power transmission to maintain reliability. To reduce dynamic driving power fluctuations, this paper proposes a design for staggered bipolar transmitter track with a corresponding X-type receiver for electric vehicles. Through a staggered magnetic field configuration, the proposed staggered bipolar track structure supports inter-operable coupling with appropriately sized bipolar receiver oriented for traveling or lateral coupling. When paired with the X-type receiver, only a uniphase receiver is sufficient to achieve smooth traveling power output across full lateral misalignment range and track module spacing up to 50% of one transmitter length, without requiring additional auxiliary coils or circuitry. A 3.3 kW dynamic prototype was built based on the designed magnetic coupler and circuit parameters. Experimental results show that, without increasing width, by adjusting the pole shoe positions, the X-type receiver can adapt to staggered bipolar track module spacing of up to 125 mm, with output voltage fluctuation kept below 2.83% during aligned motion, and DC/DC efficiency reaches 91.04%.