Electric Vehicle (EV), magnetic properties, wireless power transfer, inductive charging, circular coil


Electric vehicles (EV) have been introduced in the recent years due to public awareness of the effect of gas emission from traditional cars and the extinction of petroleum natural resources. For charging EV, dynamic wireless charging is considered in this paper. This is because it is more convenient and saves charging time since it charges the electric vehicle while moving. The main challenge of this process is to maintain a high amount of power transfer from primary to secondary coil. One of the factors contributing to a good power transfer is the size of the coil [1]. There are various designs of coil for wireless charging of electric vehicles (EV). Among the most common designs are circular pad (CP), rectangular pad (RP), double-D pad (DDP), and double-D quadrature pad (DDQP). In this paper, circular pad (CP) is chosen for use, due to its simplicity in design and good electrical and magnetic properties. Three different coil pair sizes are tested to find the most suitable coil pair for the primary and secondary pads that has the maximum power transfer and is least sensitive to misalignment. The magnetic properties have been investigated to obtain the highest value of magnetic flux. The geometry design of the pads and simulation was done using COMSOL Multiphysics software. From the simulation, it was found that the unsymmetrical coil pair gives high magnetic strength when the outer diameters of the primary and secondary coils have the same value.

ABSTRAK: Kenderaan Elektrik (EV) telah diperkenalkan sejak beberapa tahun ini hasil kesedaran awam tentang kesan pembebasan gas dari kenderaan lama dan pengurangan sumber asli petroleum. Kajian ini berkaitan pengecas dinamik tanpa wayar bagi mengecas EV. Ini kerana pengecas ini lebih sesuai dan jimat masa mengecas kerana kenderaan elektrik dicas ketika bergerak. Cabaran utama proses ini adalah mengekalkan pemindahan tenaga yang tinggi daripada gegelung primer kepada gegelung sekunder. Salah satu faktor bagi mendapatkan pemindahan tenaga yang tinggi adalah saiz gegelung wayar [1]. Terdapat pelbagai bentuk gegelung bagi mengecas kenderaan elektrik (EV) tanpa wayar. Antaranya adalah pad membulat (CP), pad segiempat tepat (RP), pad berganda-D (DDP), dan pad kuadratur berganda-D (DDQP). Kajian ini telah menggunakan pad membulat (CP) kerana reka bentuknya yang ringkas dan ia mempunyai sifat elektrikal dan magnatik yang baik. Tiga pasang gegelung berbeza telah diuji bagi mendapatkan pasangan gegelung pad primer dan sekunder yang paling sesuai di mana ianya mempunyai pemindahan tenaga maksima dan paling kurang sensitif pada ketidakjajaran. Sifat magnet telah diuji bagi mendapatkan nilai fluks magnet tertinggi. Rekabentuk geometri pad dan simulasi telah dijalankan menggunakan perisian Multifizik COMSOL. Hasil simulasi mendapati pasangan gegelung yang tidak simetri telah menghasilkan kekuatan magnetik tertinggi apabila diameter luaran gegelung primer dan sekunder mempunyai nilai sama.


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K. Aditya, V. K. Sood, and S. S. Williamson. (2017) Magnetic characterization of unsymmetrical coil pairs using archimedean spirals for wider misalignment tolerance in ipt systems. IEEE Transaction on Transportation Electrification, 3(2): 454–463.

R. Bosshard and J. W. Kolar. (2016) Inductive Power Transfer for Electric Vehicle Charging. IEEE Power Electronics Magazine: 22–30.

Malaysian Green Technology Corporation "Low Carbon Mobility" []

S. Yusoff, L. De Lillo, P. Zanchetta, and P. Wheeler. (2012) Predictive Control of a direct AC/AC matrix converter power supply under non-linear load conditions. 15th International Power Electronics and Motion Control Conference Expo. EPE-PEMC 2012 ECCE Europe: 1–6.

S. Yusoff, L. De Lillo, P. Zanchetta, P. Wheeler, P. Corte?s, and J. Rodri?guez. (2012) Predictive control of a direct AC/AC matrix converter for power supply applications. 6th IET International Conference on Power Electronics, Machines and Drives (PEMD 2012): A92–A92.

P. S. R. Nayak and D. Kishan. (2018) Performance analysis of series/parallel and dual side LCC compensation topologies of inductive power transfer for EV battery charging system. Front. Energy: 1–14.

C. Liu, C. Jiang, C. Qiu. (2017) Overview of Coil Designs for Wireless Charging of Electric Vehicle. IEEE PELS Workshop on Emerging Technologies: Wireless Power Transfer (WoW): 15–18.

A. Ahmad, M. S. Alam, S. Member, and R. Chabaan. (2018) A Comprehensive Review of Wireless Charging Technologies for Electric Vehicles. IEEE Transaction on Transportation Electrification, 4(1): 38–63.

M. Mohammad and S. Choi. (2018) Optimization of ferrite core to reduce the core loss in double-D pad of wireless charging system for electric vehicles. Conference Proceedings - IEEE Applied Power Electronics Conference and Exposition (APEC): 1350–1356.

A. Tejeda, C. Carretero, J. T. Boys, and G. A. Covic. (2017) Ferrite-Less Circular Pad with Controlled Flux Cancelation for EV Wireless Charging. IEEE Transactions on Power Electronics, 32(11): 8349–8359.

M. Budhia, G. Covic, and J. Boys. (2010) A new IPT magnetic coupler for electric vehicle charging systems. IECON Proceedings- Industrial Electronics Conference: 2487–2492.

W. Chen, C. Liu, C. H. T. Lee, and Z. Shan. (2016) Cost-effectiveness comparison of coupler designs of wireless power transfer for electric vehicle dynamic charging. Energies Journal: 1-13.

S. Wang, Y. Guo, and D. Dorrell. (2017) Analysis of Rectangular EV Inductive Charging Coupler. 12th IEEE Conference Industrial Electronics and Applications: 285–291.

L. Xiang, Y. Sun, Z. Ye, Z. Wang, and S. Zhou. (2016) Combined primary coupler design and control for EV dynamic wireless charging system. IEEE PELS Workshop on Emerging Technologies: Wireless Power, WoW 2016: 174–179.

M. Budhia, S. Member, J. T. Boys, G. A. Covic, and S. Member. (2013) Development of a Single-Sided FluxMagnetic Coupler for Electric Vehicle IPT Charging Systems. IEEE Transactions on Industrial Electronics, 60(1): 318–328.

S. Li and C. C. Mi. (2014) Wireless Power Transfer for Electric Vehicle Applications. IEEE Journal of Emerging and Selected Topics in Power Electronics, 3(1): 4–17.

K. A. Grajski, R. Tseng, and C. Wheatley. (2012) Loosely-Coupled Wireless Power Transfer: Physics, Circuits, Standards. IEEE MTT-S International: 9–14.



2020-01-20 — Updated on 2020-01-20


How to Cite

Zaini, S. A., Yusoff, S. H., Abdullah, A. A., Khan, S., Abd Rahman, F. ., & Nanda, N. N. . (2020). INVESTIGATION OF MAGNETIC PROPERTIES FOR DIFFERENT COIL SIZES OF DYNAMIC WIRELESS CHARGING PADS FOR ELECTRIC VEHICLES (EV). IIUM Engineering Journal, 21(1), 23–32.



Electrical, Computer and Communications Engineering

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