A High Power Density and Low Loss DWPT Two-Phase Rail With II-Type Core and Interval Lap Winding

The dynamic wireless power transfer (DWPT) system with a two-phase bipolar narrow rail has the advantages of low power fluctuation and large lateral tolerance. Traditional two-phase systems not only feature numerous magnetic cores and windings, but also have shortcomings in power loss and power density. Due to the use of a dual full bridge inverter, its number and control of switching devices are also complex. A high power density and low loss DWPT two-phase rail with II-type ferrite magnetic tooth and interval lap winding is proposed to improve power loss and power density. A circuit topology and control method with a three-leg inverter is used to simplify the system. The models of circuits and magnetic circuits are analyzed, and simulations and experiments are conducted. The proposed two-phase transmitter has a 38.5% reduction in wire usage and a ferrite core volume decrease of 31%, while the coupling coefficient increases by 37.9%. Experimental results for a 10-kW system show that the transmitter loss of the two-phase magnetic coupler is 30% lower than that of the single-phase transmitter. At 10 kW power output, the dynamic efficiency of the system from dc to dc maximum efficiency is 87%, and the mean efficiency is 84%. A typical location dc to dc system efficiency is 86%, the magnetic coupler efficiency is 90%. The results indicate a significant improvement in power density and power loss. This article is accompanied by a video of the system dynamic charging.