Development of a Single-Sided Flux Magnetic Coupler for Electric Vehicle IPT Charging Systems

Abstract

Inductive power transfer is a practical method for recharging electric vehicles because it is safe, convenient, and reliable. The performance of the magnetic couplers that transfer power determines the overall feasibility of a complete system. Circular couplers are the most common topology in the literature; however, they have fundamentally limited coupling. Their flux patterns necessarily limit the operational air gap as well as tolerance to horizontal misalignment. A new polarized coupler topology [referred to as a double D (DD)] is presented, which overcomes these difficulties. DDs provide a charge zone five times larger than that possible with circular pads for a similar material cost and are smaller. A 0.31-m 2 DD enables 2 kW of power transfer over an oval area measuring 540 mm × 800 mm with a 200-mm air gap. Leakage magnetic fields have been investigated and show that circular and DD couplers operating under similar power transfer conditions produce similar levels. Both topologies can be designed and operated to ensure compliance with international guidelines.Index Terms-Contactless power transfer, magnetic analysis, magnetic fields.

A Comparative Study of Flux Cancellation Among Multiple Interconnected Modular Pads in Lumped Ipt System

“…The accuracy of this magnetic analysis tool has been validated in previous research with experimental results [6]. The aim of this study is to provide a guidance for modular IPT system design.…”

“…A lower R L will result in a higher Q 2 but lead to higher current losses and stresses in components. Therefore, Q 2 is typically constrained to 4-6, and P un becomes the most direct and fair index to assess the power transfer capability [6]. …”

Research and Design of Wireless Charging System of Electric Vehicles

“…In 1890, Nikola Tesla proposed the idea of wireless charging, but without great development due to technical constraints [7] . In the 1990s, the University of Auckland, New Zealand proposed a lot of novel structures to compensate for the coil design, in order to solve the problem of parking coil alignment [8] and proposed a two-way transmission mechanism of energy in the power grid and electric vehicles for the energy transfer process [9] . Today's wireless charging technology was originated from the magnetic resonance theory proposed by MIT in 2007 [10] .…”

Dynamic Wireless Charging for Roadway-Powered Electric Vehicles: A Comprehensive Analysis and Design

“…From the perspective of the coil design, a new polarized coupler topology was presented to improve the position-tolerant performance for IPT systems [7]. Then, the fundamental design of the bipolar magnetic coupler was introduced for the primary control [8].…”