Seung-Young Ahn

In this paper, we introduce the On-line Electric Vehicle (OLEV) system and its non-contact power transfer mechanism and propose some techniques for the reduction of electromagnetic fields (EMFs) from the power line and the vehicle itself. By applying a metallic plate shield, horizontal/vertical shield, and connecting wire for loop cancellation, the low frequency EMFs have been significantly reduced. Simulation and measurement results for application to vehicles currently in service are also give

In this paper, we introduce the On-Line Electric Vehicle (OLEV) system and its non-contact power transfer mechanism. We propose the design methodology to maximize the wireless power transfer capability and power transfer efficiency and to minimize the electromagnetic field (EMF) from the wireless power transfer system in OLEV. By using the series resonant power transfer topology and vertical magnetic flux type of wireless power transfer system for transformer structure, the power transfer capabi

This paper proposes an autonomous coil alignment system (ACAS) for electric vehicles (EVs) with dynamic wireless charging (DWC) to mitigate the reduction in received power caused by lateral misalignment between the source and load coils. The key component of the ACAS is a novel sensor coil design, which can detect the load coil’s left or right position relative to the source coil by observing the change in voltage phase. This allows the lateral misalignment to be estimated through the wireless p

PICTURE AN ALL-ELECTRIC VEHICLE cruising down the highway, emitting little noise and no noxious fumes. It's such an improvement that you have to wonder why only a handful of all-electric vehicles are now available on the mass market. · Here's a big reason: Picture the driver of that same car getting a call from a relative living far away who needs immediate help. Suddenly, the driver's eyes become riveted on the most important indicator on the dashboard: the estimated number of kilometers that t

As wireless power transfer (WPT) technologies emerge in a wide range of applications including public transportation, many expect that applying the technology to the current railway systems will bring positive effects to current railway systems. In this paper, we introduce design methodology of a WPT system for railway application. Fundamental principles of magnetic fields and a WPT circuit are first analyzed, and advantages and efficiency of a possible train system are discussed. It then examin

An autonomous coil alignment system (ACAS) using fuzzy steering control is proposed for vehicles with dynamic wireless charging. The misalignment between the power receiver coil and power transmitter coil is determined based on the voltage difference between two coils installed on the front-left/front-right of the power receiver coil and is corrected through autonomous steering using fuzzy control. The fuzzy control is chosen over other control methods for implementation in ACAS due to the nonli

In this paper, we proposed an effective coil design for electromagnetic field (EMF) noise reduction from the wireless power transfer system by using quadruple coils in transmitter and receiver for laptop computer application. By using quadruple coils for transmitter and receiver, EMF noise was significantly reduced with negligible change in induced voltage. 3D simulations and the field distributions are shown and the pros and cons are of the quadruple coil designs are discussed.

Wireless power transfer systems are increasingly used as a means of charging implantable medical devices. However, the heat or thermal radiation from the wireless power transfer system can be harmful to biological tissue. In this research, we designed and implemented a wireless power transfer system-based implantable medical device with low thermal radiation, achieving 44.5% coil-to-coil efficiency. To suppress thermal radiation from the transmitting coil during charging, we minimized the ESR va

In the mechanism of wireless power transfer in on-line electric vehicle (OLEV), the design of magnetic field
\nis the key technology to determine its electrical performance of power transfer capacity, transfer efficiency,
\nand electromagnetic field (EMF) level. To satisfy all the requirements, systematic approach for optimization
\nof design parameters is required. Even though shielding for reduction of EMF can be applied independently,
\nthe shielding effectiveness of the appli

In this paper, we proposed an optimized shield design for electromagnetic field (EMF) reduction from the wireless power transfer (WPT) system. Three different cases of shield design are examined in terms of strength of EMF and mutual inductance, which is directly related to power transfer efficiency. Analysis results show that when using both ferrite and conducting sheets as a shield for transmitter and receiver coils, a leakage magnetic field can be significantly reduced with negligible change

This paper presents an efficient coil design for a mm-sized micro-robot which generates a propulsion force and torque and receives electrical energy using a wireless power transfer system. To determine the most efficient coil structures and produce propulsion and torque on the micro-robot, both helical and spiral coil modeling was conducted, and analytical formulations of the propulsion force and torque were derived for helical and spiral coil structures. Additionally, the dominant dimensional f

In this paper, we propose a method of wirelessly torque transfer (WTT) and power (WPT) to a drug pump, one of implantable medical devices. By using the magnetic field generated by the WPT system to transfer torque and power to the receiving coil at the same time, applications that previously used power from the battery can be operated without a battery. The proposed method uses a receiving coil with magnetic material as a motor, and can generate torque in a desired direction using the magnetic f

This paper analyzes how over-coupled coils affect odd harmonic current and electromagnetic interference (EMI) in a wireless power transfer (WPT) system, and proposes design considerations for series inductors to solve the EMI problem. When the air gap of the coils of the WPT system decreases below a certain level and the coils are over-coupled, the odd harmonic component of the input impedance of the system decreases and odd harmonic currents increase. The increase in the odd harmonic components

Wirelessly powered medical microrobots are often driven or localized by magnetic resonance imaging coils, whose signal-to-noise ratio is easily affected by the power transmitter coils that supply the microrobot. A controlled single-sided wireless power transmitter can enhance the imaging quality and suppress the radiation leakage. This paper presents a new form of electromagnet which automatically cancels the magnetic field to the back lobes by replacing the traditional circular coils with a thr

It is necessary to reduce the crosstalk noise in high-speed signaling channels. In the channel routing area, the tabbed routing pattern is used to mitigate far-end crosstalk (FEXT), and the electrical length is controlled with a time domain reflectometer (TDR) and time domain transmission (TDT). However, unlike traditional channels having uniform width and space, the width and space of tabbed routing changes by segment, and the capacitance and inductance values of tabbed routing also change. In