Novel Core Structure and Iron‐Loss Modeling for Contactless Power Transfer System of Electric Vehicle

Abstract

SUMMARYA contactless power transfer system for electric vehicles must have high efficiency, a large air gap, good tolerance to misalignment in the lateral direction, compactness, and light weight. In this paper, a new 1.5-kW transformer has been developed using a novel H-shaped core which is more efficient, more robust to misalignment, and lighter than previous rectangular cores, to satisfy these criteria, and its characteristics are described. An efficiency of 95% was achieved across a 70-mm mechanical gap. Iron-loss modeling of the equivalent circuit is also presented. The calculated efficiency using this model shows good agreement with experimental results.

Power Flow Control of a Power Conversion Circuit for Contactless Power Transformer Systems with Coil Misalignment

“…The phase difference is found to be 4.19 • and the power factor to be cos 4.19 • #∼ 0.997. (1) and (3) is used for carrier comparison, resulting in waveforms that differ in each half interval. When x = 20 mm, the zero-crossing points of i s and v s shift and the power factor ceases to be 1.…”

“…Research on applications to electric vehicles and railway cars has been underway in recent years [1][2][3][4]. Consequently, they have various advantages, including being maintenance-free, with no exposure of the charging element, no risk of electric shock, no component wear, and no contact noise.…”

A Method for Designing a High‐Power Contactless Power Transformer Considering Reactive Power

“…As a result, it has the advantages of ease of maintenance and problem‐free operation because problems such as contact failures, current leakage, and shorts do not occur. Applications have already been realized at low power levels in electric toothbrushes and electric shavers, and research on its use in electric vehicles is also being performed . This technology has reached several kilowatts to tens of kilowatts, but in order to extend it further in the future, the establishment of an optimal design method at even higher power and consistent with the applications in question is essential.…”