Comparison of magnetic coupling structures for IPT systems

Abstract

Purpose

Inductive power transfer (IPT) is a hands free user charging system, which allows the transfer of energy over a large air gap without physical contact. The purpose of this paper is to evaluate two magnetic coupling structures and its applicability to EVs charging systems.

Design/methodology/approach

A brief introduction of IPT systems is initially presented, with the characterization of the chosen resonant topologies, series uncompensated (SU) and series parallel (SP). The magnetic coupling structures (MCSs) are then investigated and the principal characteristics required for EVs applications are outlined. The circular and the DD magnetic coupling structures are chosen due to its inherent advantages and a description of both physical and electrical most important aspects are made. Finally, different simulation and experimental results are analyzed and discussed for both magnetic structures.

Findings

The SU topology is suitable for applications with low voltages sources at the cost of a more attuned control. The DD pad allows a higher power transfer when compared with the circular pad, with better efficiency for the same working conditions. The DD pad is more tolerant to misalignment in the axis y while the circular pad is independent of the misalignment direction. Both modeled pads can transfer at least 5 kW without saturating the core.

Originality/value

This paper analyzes and compares the power transfer capability, misalignment tolerance and core saturation levels of the selected pads.

Citation

Marques, E.G. and Mendes, A.M.S. (2015), "Comparison of magnetic coupling structures for IPT systems", COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, Vol. 34 No. 2, pp. 514-530. https://doi.org/10.1108/COMPEL-08-2014-0219