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This paper presents an adaptation method of equivalent factor in equivalent consumption minimization strategy (ECMS) of fuel cell hybrid electric vehicle (FCHEV) using hilly road information. Instantaneous optimization approach such as ECMS is one of real-time controllers. Furthermore, it is widely accepted that ECMS achieves near-optimum results with the selection of the appropriate equivalent factor. However, a lack of hilly road information no longer guarantees near-optimum results as well as charge-sustaining of ECMS under hilly road conditions. In this paper, first, an optimal control problem is formulated to derive ECMS analytical solution based on simplified models. Then, we proposed updating method of equivalent factor based on sensitivity analysis. The proposed method tries to mimic the globally optimal equivalent factor trajectory extracted from dynamic programming solutions.

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.

This study investigates how hilly road profiles affect the optimal energy management strategy for fuel cell hybrid electric vehicle (FCHEV) with various battery sizes. First, a simplified FCHEV model is developed to describe power and energy flows throughout the powertrain and evaluate hydrogen consumption. Then, an optimal control problem is formulated to find the globally optimal energy management strategy of FCHEV over driving cycles with road elevation profile. In order to solve the optimal energy management problem of the FCHEV, Dynamic Programming, a dynamic optimization method, is used, and their results are analyzed to find out how hilly road conditions affect the optimal energy management strategies. The results show that the optimal energy management with a smaller battery tends to actively prepare (e.g. pre-charge/pre-discharge) for uphill/downhill roads in order not to violate the battery state of charge (SoC) bounds.

Upon the need of a highly efficient transmission system for conventional cars and the hybrid electric vehicle (HEV) purposes, in the paper, clutchless geared transmission system (CGST) by removing the clutch and incorporating a planetary gear system connected to a motor is newly proposed. The dynamic analysis of CGST operations is carried out, using the lever analogy of planetary gear. The state space model and the mathematical model of CGST structure are derived. Through the simulations of CGST operations, input-output tests and gear shifts are performed. To verify the simulation result, reduced size of CGST testbench is developed and experimented.

In order to minimize the greenhouse effect due to the emission of CO2, automobile manufactures have been developing battery-powered plug-in automobiles with re-chargeable Lithium Polymer batteries. However, these pure electric vehicles (EVs) are not welcomed in the market because the Lithium batteries are heavy and still expensive with limited rechargeable cycles. Furthermore, charging time and relatively short driving range obstruct the commercialization of EVs. To solve the problems, KAIST proposed four generations of On-Line Electric Vehicles (OLEVs), a sort of roadway wireless powered EVs. This paper summarizes the progress of the OLEV developments. Four generations of OLEV were demonstrated for different underground electric power rails and pick-ups. The air-gap of the 1st generation OLEV car is 1 cm and the input to output power efficiency is 80 % with 3 kW output power.

An electric motor for regenerative braking in front-wheel-drive hybrid electric vehicle is only connected to the front axle, and mechanical friction braking can be independently applied on each of the 4 wheels. Excessive regenerative braking only at front wheels to improve fuel economy can cause under-steer and eventually vehicle instability. Nonlinear tire characteristic may cause this vehicle instability in severe cornering with hard braking. Therefore, cooperative braking control strategy has to be considered nonlinear tire characteristic for guaranteeing the vehicle stability while enhancing the braking energy recovery. This paper is to compare the performance of cooperative braking control strategy according to consider the influence of braking force on the lateral force. Carsim™ software is used to evaluate the performance of cooperative regenerative braking control regarding to the vehicle stability and regenerative braking efficiency.

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).