Analysis On The Co Re And Shield Structure Of Wireless Charging Systems For Electric Vehicles

The ferrite core structure and the shield structure of a magnetic coupler in a wireless charging system for electric vehicles are investigated in this thesis.In chapter ?,the commonly used magnetic coupler structure in an electric vehicle(EV)wireless charging system are summarized.And the shielding methods for electromagnetic field are reviewed.In chapter ?,the ferrite core structure are investigated.The loss model of the magnetic coupler is provided.Three different kinds of ferrite core structures,i.e,plate shape,strip shape and net shape,are investigated and compared.The effect of the vehicle chassis and the shields are considered.Experiments are carried out to verify the analysis.In chapter ?,the shield structure is investigated.The effect of the dimension parameters of a shield have on the system efficiency and electromagnetic field is studied.The shielding effects of a plate-shape shield and a ring-shape shield in misalignment situations are also studied and compared.In chapter IV,a 3.7 kW wireless power transfer system for EVs are designed and built based on the study in the former chapters.Parameter design of the magnetic coupler is provided.Using Bluetooth module to communicate between the transmitting and receiving side,Close-loop control is realized by phase-shifting control strategy.The peak DC-DC efficiency is 94%with 3.7 kW output power and 20 cm air gap distance.