Design and Analysis of Ferrite Less Magnetic Coupler With Improved Dynamic Performance Characteristics for EV Applications

Abstract

Dynamic wireless charging (DWC) is making its way to charge electric vehicles (EVs) on the go. It has the potential to reduce both EV battery size and cost. However, the dynamic wireless power transfer (DWPT) system needs to be optimized before it can become widely available in the market. This includes designing compact magnetic couplers that can easily be placed under EVs and can handle both static and dynamic charging. This article recommends a single-sided flux-generating magnetic coupler with optimized performance factors. The proposed coupler has a better coupling coefficient and mutual inductance with considerably lower self-inductance when compared to conventional magnetic couplers. When tested for DWPT operation with three symmetric transmitters, the proposed coupler offers low mutual inductance with neighboring transmitters and naturally decouples with the third transmitter, reducing the effort required for decoupling multiple transmitters. The proposed receiver offers only 1.3% pulsating output voltage. Also, the proposed optimization helps to achieve ${36}{0}^{\circ }$ rotational misalignment tolerance with zero null zone present in its output I–V characteristics. To validate the proof of concept, a 1.6 kW output power dynamic using $LCC$ -S compensation at 85 kHz resonance frequency is designed for 200 mm air-gap, with maximum recorded efficiency to be dc–dc ~93%.