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.

This study provides an approach investigation of U and I ferrite core geometrics to improve the power efficiency for Electric Vehicle (EV) inductive wireless charging in dynamic mode. Dynamic wireless charging (DWC) enables recharging of battery pad during the vehicle is on the road. Hence, the design of battery pad must deal with two main factor that led to power leakage such air gap and misalignment. Using ferrite magnetic core, it improves the power transferred by reduce the leakage magnetic radiation between primary and secondary side. Different conditions are investigated on U and I core. The first and second condition is U or I core only at primary side and secondary U or I core only at the secondary side. The last condition is both at primary and secondary side of U or I ferrite core. The purpose of this project is to design a prototype of EV thru several method, design proposed, circuit simulation, pair simulation and prototype development. NI Multisim are used to simulate circuit of WPT for operation validity.

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The technology of dynamic Wireless Power Transfer (WPT) has been accepted in the Electric Vehicle (EV) industry. Recently, for a stationary EV charging system, the existence of a ferrite core improves power efficiency. However, for dynamic wireless charging, the output power fluctuates when the EV moves. Two main obstacles that must be dealt with is air-gaps and misalignment between the coils. This paper investigates clear design guidelines for fabrication of an efficient Resonant Inductive Power Transfer (RIPT) system for the EV battery charging application using a ferrite core. Two different geometry shapes of ferrite core, U and I cores, will be investigated and tested using simulation and experimental work. The proposed design was simulated in JMAG 14.0, and the prototype was tested in the laboratory. The expected output analysis from these two techniques was that the power efficiency of the ferrite pair should first be calculated. From the analysis and experimental results, it is seen that the pair of ferrite cores that used a U shape at the primary and secondary side provides the most efficient coupling in larger air-gap RIPT application with 94.69% on simulation JMAG 14.0 and 89.7% from conducting an experiment. ABSTRAK: Teknologi Alih Kuasa Wayarles (WPT) dinamik telah diterima pakai dalam Kenderaan Elektrik (EV). Baru-baru ini, kewujudan teras ferit dalam sistem pengecasan pegun EV dapat meningkatkan kecekapan kuasa. Namun, kuasa pengecasan ini akan berubah apabila EV bergerak bagi sistem pengecasan wayarles secara dinamik. Dua halangan utama yang harus ditangani adalah ketidakjajaran dan jarak antara dua gegelung. Kajian ini merupakan garis panduan yang jelas mengenai rekaan fabrikasi dan kecekapan sistem Alih Kuasa Induktif Resonan (RIPT) bagi aplikasi pengecasan bateri EV menggunakan teras ferit. Dua bentuk geometri teras ferit, iaitu teras U dan I telah dikaji dan diuji menggunakan simulasi dan eksperimen. Rekaan ini telah disimulasi menggunakan JMAG 14.0 dan prototaip diuji di dalam makmal. Kedua-dua teknik ini diharapkan dapat menghasilkan kecekapan kuasa yang sama. Dapatan kajian menunjukkan kedua-dua teras ferit pada sisi primer dan sekunder berbentuk U mempunyai gandingan paling efisien bagi jarak paling besar antara 2 gegelung menggunakan aplikasi RIPT dengan 94.69% simulasi JMAG 14.0 dan 89.7% secara eksperimen.