An Improved and Integrated Design of Segmented Dynamic Wireless Power Transfer for Electric Vehicles

Abstract

This paper describes improvements in a segmented dynamic wireless power transfer (DWPT) system for electric vehicles (EVs), and aims to offer a stable charging method for high-power applications. An integrated design is presented, including the modified switching sequence, the size of segmented transmitters, and parallel inverter technology for high-power applications. Three consecutive transmitters mounted on the rail track are energized according to the position of the pickups. This three-consecutive-transmitter group is comprised of a Q-shaped coil, a DD-shaped coil, and a Q-shaped coil again (QDDQ). QDDQ is used as an elementary energized group to optimize the number of energized transmitters and mitigate the output voltage variation. The entire DWPT system is designed with finite element analysis (FEA) and studied with circuit topologies. Overall, an experimental prototype for dynamic charging is built to verify the overall performance, which shows a great agreement with the theoretical analysis. In this prototype, there are five transmitters and one receiver. All dimensions are 500 mm × 500 mm. The proposed system has been validated to realize 500 V constant output voltage with approximately 85% dc-dc efficiency from the 100 Ω to 200 Ω load conditions. A 2.5 kW maximum output power occurs at the 100 Ω load condition.