Analysis on Misalignment Tolerable Coil Structures for Achieving Fast Wireless Charging Solution for Electric Vehicles

Abstract

Wireless Power Transfer (WPT) Technology is proliferating the domain of battery powered devices for its ability to offer higher security and mobility while charging. WPT is yet to mature in terms of Power Transfer Efficiency (PTE) and Transferred Power (TP). WPT Technology has the potential to become the standard charging solution for Electric Vehicles (EVs). Misalignment and long charging distances are unavoidable in wirelessly charged EVs. These are causing more leakage inductances in the system and adversely cut-downs the PTE and TP. These inductances result in low coupling factors and lead to low charging speed. Various coil topologies are examined and modelled in this paper to attain a good coupling factor and magnify the charging speed. The impact of coil structures on the characteristics of the WPT system is discussed. A thorough simulation analysis is performed on the distribution of magnetic fields over the coils. A new misalignment tolerable coil structure is proposed and simulated here. It effectively counters the minor misalignments and improves the coupling factor between the transmitter and receiver coils in the WPT system. The proposed coil design consumes additional material and occupies some space, however, it is enabling the fast wireless charging solution.