Magnetic Coupling Characteristics and Efficiency Analysis of Spiral Magnetic Power Pads for Inductive WPT System


  • Dharavath Kishan E-mobility research laboratory, Dept. of Electrical and Electronics Engineering, National Institute of Technology Karnataka, Surathkal, India



Electric vehicles, inductive wireless power transfer, magnetic power pads, mutual inductance


The inductive wireless power transfer system (IWPT) for electric vehicle battery charging works based on the principle of mutual induction (MI). The amount of power transfer from source to vehicle battery be contingent on the mutual inductance (MI) within the inductively coupled pads. This mutual inductance depends on the type of the inductive power pads, the distance among them, their positioning etc. This paper develops and study the inductive coupling characteristics of identical spiral circular and square inductive power pads. The coupling characteristics at various misalignments with different vertical distance between the coils is presented. In this work, the inductive power pads without using ferrite bars, and with ferrite bars are considered. The coupling characteristics of the spiral circular and square are computed using FEM simulations and validated with experimental results. This paper also investigated the power loss and efficiency analysis of the spiral inductive pads of the resonant IWPT system.

Author Biography

Dharavath Kishan, E-mobility research laboratory, Dept. of Electrical and Electronics Engineering, National Institute of Technology Karnataka, Surathkal, India

Dharavath Kishan received the B. Tech degree in Electrical and Electronics Engineering and M. Tech degree in Power Electronics from Jawaharlal Nehru Technological University Hyderabad respectively in 2011 and 2013 and he received his PhD degree from National Institute of Technology Tiruchirappalli in 2018. Currently he is working as Assistant Professor in Department of E & E Engineering at National Institute of Technology Karnataka (NITK), Surathkal, India. Prior to joining NITK he worked as Assistant Professor at Faculty of Science and Technology, IFHE Hyderabad. Dr Kishan current research interests include power electronics and its applications in electric vehicles, wireless power transfer and transportation electrification. He has published 16 research papers in reputed journals and peer reviewed international conferences. He is also delivered guest lectures at various events on Wireless Power Transfer for electric vehicles. He is also an IEEE Senior Member and IAS, PELS & IES Society member. Dr Kishan is also an active reviewer for various reputed IEEE transactions like IEEE Transactions on Electromagnetic compatibility, IEEE Transactions on Industrial Electronics, IEEE Transactions on vehicular Technology, and IEEE Access, IET Renewable Power Generation. He has guided two master level students in the area of power electronics and currently guiding one master and Five PhD students in the area of Power Electronic Applications.


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How to Cite

Kishan, D. . (2022). Magnetic Coupling Characteristics and Efficiency Analysis of Spiral Magnetic Power Pads for Inductive WPT System. Distributed Generation &Amp; Alternative Energy Journal, 37(05), 1703–1720.