Coupling coefficient of resonators

Quantum mechanics

Engineering

Ferrite (magnet)

Telecommunications

Power (physics)

Computer science

Electric vehicle

Power dividers and directional couplers

Physics

Resonator

Automotive engineering

Ferrite core

Maximum power transfer theorem

Wireless power transfer

Hybrid coupler

Solenoid

Wireless

Electromagnetic coil

Electrical engineering

IEEE Journal of Emerging and Selected Topics in Industrial Electronics

The lateral misalignment for static electric vehicle (EV) wireless charging could be much larger than 100 mm if the parking assistance systems are unavailable. This article proposes a split flat solenoid coupler (SFSC) to significantly extend the lateral misalignment and reduce the copper and ferrite usage. To obtain a good balance among coupling, misalignment tolerance, and cost, an optimization method for SFSC is proposed where the size limitations and ferrite tile specifications are considered. The optimized SFSC is compared with two magnetic couplers recommended in SAE J2954 in terms of coupling coefficient and misalignment tolerance. To eliminate the impact of coil size and make the comparison fair, the quantified misalignment tolerance is introduced. The proposed SFSC provides much better misalignment tolerance than the recommended couplers. A 1000-W prototype is built to show the advantages of the proposed coupler. The output current keeps unchanged when the lateral misalignment is as high as 400 mm. A highest power transfer efficiency, from dc input to dc output, of 89.12% is achieved when the output power is 1000 W.

A Novel Misalignment Tolerant Magnetic Coupler for Electric Vehicle Wireless Charging