Improved core shape of contacless transformer for LRT system

Abstract

The crescent interest in greener transportation systems increases the search for coherent, intelligent, efficient and more cost effective solutions. In this scenarios Light Rail Transits are becoming more and more used. In the direction or more flexible and safer system, contactless power systems are being used in LRT. This paper present an Improved core shape for the contactless transformer used in a model LRT system. The electrical and the magnetic analysis of the transformer are performed and compared to a Planar core transformer. The Improved core allows to suppress the utilization of core in the secondary reducing the weight in the train car with keeping the required transmitting power and input voltage.

Increase in Robustness against Effects of Coil Misalignment on Electrical Parameters Using Magnetic Material Layer in Planar Coils of Wireless Power Transfer Transformer

“…The starting point for this research was the simplest approach for a WPT transformer for an offline WPT system for LRT, namely a round planar coil with a magnetic material used to increase the magnetic flux. As shown in [37], it is possible to use a magnetic material only on the primary side and still generate enough flux to induce the required amount of power on the secondary side. In [37], the possible eddy currents induced in the train carbody were not taken into consideration.…”

“…As shown in [37], it is possible to use a magnetic material only on the primary side and still generate enough flux to induce the required amount of power on the secondary side. In [37], the possible eddy currents induced in the train carbody were not taken into consideration. As shown in Tan et al [38] and in Wen and Huang [39], the presence of a metallic plate to the WPT transformer affects the inductance values and the generated eddy currents could generate important losses.…”

“…The coils were constructed using litz wire to reduce the proximity effect and eddy currents between the turns. The detailed characteristics of litz wire can be found elsewhere [37]. The coil shape was preliminarily designed using computer-aided design (CAD) software to ensure that the total size and turn positions met the support base constraints.…”