In-Soo Suh

Coil Design and Shielding Methods for a Magnetic Resonant Wireless Power Transfer System

In this paper, we introduce the basic principles of wireless power transfer using magnetic field resonance and describe techniques for the design of a resonant magnetic coil, the formation of a magnetic field distribution, and electromagnetic field (EMF) noise suppression methods. The experimental results of wireless power transfer systems in consumer electronics applications are discussed in terms of issues related to their efficiency and EMF noise. Furthermore, we present a passive shielding method and a magnetic field cancellation method using a reactive resonant current loop and the utilization of these methods in an online electric vehicle (OLEV) system, in which an OLEV green transportation bus system absorbs wireless power from power cables underneath the road surface with only a minimal battery capacity.

Electric vehicle on-road dynamic charging system with wireless power transfer technology

The recent development in simulation speed and capacity of magnetic field, and the power electronics, the field of wireless power transfer has been developed significantly. In the future transport area, electric vehicles are considered as replacement of oil-powered internal combustion engine driven vehicles, especially for the CO2 reduction and alternative energy perspective. However, electric vehicle requires several key issues resolved in view of the heavy weight, bulky volume, and limited driving distance. In this paper, the innovative on-road dynamic wireless charging technology for electric vehicle, called OLEV, is introduced. The electric vehicle charging technology can be classified as conductive or wireless, stationary or dynamic, and slow or fast. The fast charging in the range of 100 kW of power capacity and wireless dynamic charging concept are described. Also the design concept, system architecture and development process of optimizing the magnetic flux field for the higher power transfer efficiency are described in this paper. The dynamic charging technology is also compared with the stationary conductive charging for electric vehicles, in view of its development concept and status, and practical feasibility of the innovative technology.

A proposal on wireless power transfer for medical implantable applications based on reviews

Since wireless power transfer technology (WPT) gains its popularity, broad range of application and research are performed in the field of medical implantable applications. In this paper, we review the technical status of WPT system applied to medical implant devices. As a practical application of this technology, the current achievements and challenges of wireless capsule endoscopy are reviewed and analyzed, in view of its design, functional requirement and related issues in WPT. And WPT application to artificial heart is also discussed. Based upon the analysis, we propose a research directions and WPT consideration in designing a WPT system for implantable medical applications.

EV Charging Through Wireless Power Transfer: Analysis of Efficiency Optimization and Technology Trends

This paper presents the technology trends for wireless power transfer (WPT) for electric vehicles (EV), and analyzes the factors affecting its power transfer efficiency (PTE) and describes the techniques currently used for its optimization. The review of technology trends encompasses both stationary and moving vehicle charging systems. The study of the stationary vehicle charging technology is based on developments at WiTricity and Oak Ridge National Lab (ORNL). The moving vehicle charging technology is primarily described through the results achieved by the Korea Advanced Institute of Science and Technology (KAIST). The factors affecting the PTE are determined through the analysis of the equivalent circuit of magnetic resonant coupling. The air gap between both transmitting and receiving coils along with the magnetic field distribution and the relative impedance mismatch between the related circuits are the primary factors affecting WPT efficiency. Currently the industry is looking at an air gap of 20 cm or below. To control the magnetic field distribution, KAIST has recently developed the Shaped Magnetic Field In Resonance (SMFIR) technology that uses optimized shaped ferrite material to provide a low reluctance path or maximum exposure of the magnetic field to the resonant coils. The PTE can be further improved by means of impedance matching. As a result, Delphi’s current implementation of WiTricity’s technology exhibits WPT efficiency above 90 % for stationary charging with power capacity of 3.3 kW, while KAIST has demonstrated a maximum efficiency of 83 % for moving vehicle with its On-Line Vehicle (OLEV) project with the power capacity of 100 kW.

In-wheel motor application in a 4WD electric vehicle with foldable body concept

With the growing concern on the environment and limited petroleum, the transportation field has been looking for alternative modes, vehicle segments, and improved operation strategies. On the other hand, with the growing transportation issues on urban applications in the trend of increasing numbers of mega cities and elderly populations, the personal mobility vehicle concept is being studied especially for the urban applications while maximizing the convenience of the users. This paper will introduce and review a conceptual prototype of personal mobility vehicles. The innovative design of an electric vehicle with a foldable concept will be introduced and discussed focused on the in-wheel motor assembly design and control of 4 wheel independent drive application. The required driving performance and dynamic characteristics of the vehicle are discussed and presented through the vehicle modeling considering the motor operation and control system design.

A feasibility study of an electric–hydraulic hybrid powertrain for passenger vehicles

The limitations of electrochemical batteries are one of the chief reasons that the widespread adoption of electric vehicles is slowing down. An alternative to overcome this is to use hybrid energy storage systems. One seldom explored alternative is the possibility of combining the electrical and hydraulic components of the battery in a powertrain intended for passenger vehicle use. The present research models an electrohydraulic hybrid vehicle and compares it with a baseline battery electric vehicle under an urban driving cycle. The results show a reduction in the energy consumption as well as a reduction in the battery current transients.

Development of a Foldable Micro Electric Vehicle for Future Urban Driving with Intelligent Control

There have been continuous efforts from global automotive industries with the new environmental regulations in order to reduce air pollution, to mitigate the global warming and to emphasize low carbon green growth. Micro mobility can be a new mode of transport that is being develop in order to provide a potential solution to the above issues. This paper introduces the foldable micro electric vehicle and focuses on prototype design and control architecture of that. The innovative design of folding mechanism and the motor control system without position sensing is proposed. This method uses current information from Energy Management System (EMS) to estimate position of the folding motor. In-wheel drive control system for micro mobility is proposed.

An investigation on motor-driven power steering-based crosswind disturbance compensation for the reduction of driver steering effort

This paper describes a lateral disturbance compensation algorithm for an application to a motor-driven power steering (MDPS)-based driver assistant system. The lateral disturbance including wind force and lateral load transfer by bank angle reduces the drivers steering refinement and at the same time increases the possibility of an accident. A lateral disturbance compensation algorithm is designed to determine the motor overlay torque of an MDPS system for reducing the manoeuvreing effort of a human driver under lateral disturbance. Motor overlay torque for the compensation of drivers steering torque induced by the lateral disturbance consists of human torque feedback and feedforward torque. Vehicle–driver system dynamics have been investigated using a combined dynamic model which consists of a vehicle dynamic model, driver steering dynamic model and lateral disturbance model. The human torque feedback input has been designed via the investigation of the vehicle–driver system dynamics. Feedforward input torque is calculated to compensate additional tyre self-aligning torque from an estimated lateral disturbance. The proposed compensation algorithm has been implemented on a developed driver model which represents the drivers manoeuvreing characteristics under the lateral disturbance. The developed driver model has been validated with test data via a driving simulator in a crosswind condition. Human-in-the-loop simulations with a full-scale driving simulator on a virtual test track have been conducted to investigate the real-time performance of the proposed lateral disturbance compensation algorithm. It has been shown from simulation studies and human-in-the-loop simulation results that the drivers manoeuvreing effort and a lateral deviation of the vehicle under the lateral disturbance can be significantly reduced via the lateral disturbance compensation algorithm.

Implementation Cost Comparison of Electric Vehicle Energy Replenishment Technologies for Public Transit Bus Systems

Several technologies have been developed for optimizing the use of electric vehicles, especially with regard to replenishment of the energy supply. A novel model with which to compare the implementation cost of various replenishment technologies is proposed. Petri nets were used to calculate the minimum amount of resources required to implement each of the solutions given a specific headway. Three case studies are presented, the results of which led to the conclusion that on shorter headways, battery swap systems are preferred, followed by in-motion grid-provided systems, and that on longer headways, battery recharge systems are preferred for total implementation cost. The in-motion grid-provided systems showed a lower overall operation cost over the headway range; this result indicates a potentially lower overall implementation cost if the complete life-cycle cost is taken into account.

Smart Mobility Strategy in Korea on Sustainability, Safety and Efficiency Toward 2025

Surface transportation systems encounter strong demand for improved safety, reduced congestion and enhanced throughputs which lead to continuous innovation on vehicular technologies, while meeting the need for a sustainable energy future. Applying vehicular connectivity and automated vehicle technologies to deliver a smart mobility system in view of safety, throughputs and required conveniences, will interface a core activity of intelligent transportation system (ITS) strategic planning and implementation. So far, the power source transition to electrification, either battery- or fuel cell-based, has not been fully considered globally within the future ITS strategy. Consequently a strategy for the smart mobility has been developed to 2025 at the Korean national level, of which the core approaches are described in this paper. In addition to the review on various test-bed developments and implementations in Europe, the US, and Japan, the strategic planning on technology roadmap and test-bed application by identifying and prioritizing the future road transport demand are discussed, emphasizing vehicular connectivity and electrification.