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Around the world, the major automakers are developing their strategies for conductive and wireless charging technologies, with concerted efforts to establish technical standards on wireless electric vehicle charging, mainly focused on the safety considerations and inter-operability. Wireless Charging Technology and the Future of Electric Transportation covers the current status of wireless power transfer (WPT) technology and its potential applications to the future road and rail transportation systems. Focusing on the applications of WPT technology to electric vehicle charging and the future green transportation field, Wireless Charging Technology and the Future of Electric Transportation was written collaboratively by nine experts in the field, led by Dr. In-Soo Suh, a professor and researcher from the Korean Advanced Institute of Technology (KAIST).

On-line Electric Vehicle (OLEV®) technology, developed by Korea Advanced Institute of Science and Technology (KAIST), is a breakthrough solution to the limited driving range, long battery charging time and high cost of battery of battery-powered electric vehicle. In this research, OLEV® technology was applied in the design of a FSAE®-style pure electric vehicle as one of the prototypes for OLEV® project. With this prototype, it was the first time an electric powertrain with wireless power transfer is embedded in a Formula SAE®-style prototype vehicle. This paper gives an overview of the design of the vehicle, introduction to the powertrain and performance evaluation of the vehicle.

It is a global research and development trend to introduce electric vehicle into the market in a prompt manner; however, there have been technological issues with batteries, or in general, an energy storage technology in moving vehicles. KAIST, a globally leading university majoring in science and technology in Korea, has been developing a break-through wireless power transfer technology by applying inductive power transfer technology, as demonstrated in a public park in March, 2010, which is referred to as “OLEV- On-line Electric Vehicle.” With the technology, it is possible to drive the electric powertrain and charge its battery simultaneously while the vehicle is in operation on the road. In this paper, a couple of specific noise and vibration phenomena are introduced which have been observed during the development phase of the proto-type of test vehicle.

In a vehicle NVH development and refinement phase, it is necessary to understand the source of the noise and vibration from various powertrain and drivetrain mechanisms. The noise and vibration generated by a drivetrain in a vehicle is a complicate but significant source of physical mechanism, which might become important issues in early or later phase of the vehicle development. For the diagnostic purpose of the drivetrain, a rear-wheel drive (RWD) vehicle in early development phase has been used to measure the bending and torsional vibration of the drivetrain, as well as the vehicle interior noise simultaneously, while the vehicle is running up and down under quasi-steady state on a chassis dynamometer. The lower frequency resonances of torsional and bending vibrations from the drivetrain are correlated with the vehicle interior boom or overall loudness.

Optimizing base engine design in view of performance, emission requirement, durability, and lighter weight has been a challenging work in automotive industry for a last couple of decades. While those functional requirements are designed and developed to be met, NVH requirement has been one of difficult objectives to be optimized in the design and development process, not only because of technical difficulties, but of the lesser degree of settlement of development process in a vehicle program. The combustion characteristic of an engine plays an important role in the performance, emission, and NVH development. In this paper, the engine radiation sound and mounting vibration have been measured simultaneously with the combustion pressure from each cylinder of a V8 engine while varying the engine speed under wide open throttle condition and spark timing.

Either for diagnostics purposes or NVH improvement efforts in vehicle development, it will be necessary to have both timing and spectral contents information from measured sound or vibration data. It will become especially important when the sound or vibration is induced from the impact mechanism in automotive engines, such as valve train, piston, or fuel injector etc. In this study, we will review several approaches of time-frequency representation, like Wavelet Transform, Wigner-Ville Distribution and Short-Time Fourier Transform, with their properties in view of application to practical development engineering. These techniques have been applied to practical development examples in order to identify the characteristics of the impact-induced sound and vibration [1, 9]. From the valve train noise study, it was possible to separate valve seating noise at the time of valve closing, and valve opening noise during valve opening period.