• Proceedings of the KSR Conference
• /
• 2003.10c
• /
• pp.513-518
• /
• 2003

Noises are defined as unwanted sound and invoke the physical harm and unconvenience. The higher the noise level is, the more damage peoples have. Low frequency noise is less harmful than high frequency one. In case of train, noises inside of train which is isolated from outer circumstances reduce the convenience of passenger very much. This paper reviewed the noise standard of train for urban subway and investigated the main transformer as the main noise source of train and suggested the method to diminish the noise resulted from main transformer of train and compared the measured results of before and after the improvement of main transformer.

• Proceedings of the KIEE Conference
• /
• 2006.07a
• /
• pp.78-80
• /
• 2006

High speed electric trains have nonlinear loads including converters and inverters for the control synchronous motors. Harmonic field measurements have shown that the harmonic contents of a waveform varies with time. Direct application of the harmonic assessment to the snapshot measurements would result in ambiguous conclusions depending on which instant is sampled. A cumulative probabilistic approach is the most commonly used method to solve time varying harmonics. This paper provides an in depth analysis on harmonics field measurement of the high speed electric train loads, harmonics assessment by the international harmonic standards IEC 61000-3-6 and IEEE Std. 519-1992, and harmonics simulation using EDSA program for the case study.

• Tribology and Lubricants
• /
• v.36 no.2
• /
• pp.96-104
• /
• 2020

The electric vehicle industry is rapidly developing because of enforced environmental regulations, and several studies have been conducted on the multispeed transmission to improve the fuel efficiency of electric vehicles. Among these studies, research on the power density improvement of electric vehicle transmission is critical. Thus, the optimal design of the gear train is necessary to enhance transmission efficiency. In this study, an optimal design methodology for the lightweight two-speed transmission of electric vehicles is proposed. Because a multispeed transmission has many operating conditions and equality and inequality constraints, a new gear design method that combines analytical and iterative methods is applied without using complex optimization algorithms. Sets of possible design variables are generated considering the operating conditions and various design variables. The modules and face width ratios of each stage gear that satisfy the corresponding operating conditions are analytically calculated. The volume of the gear train is calculated, evaluated, and arranged using these values to determine the optimal solution for minimizing the volume, and the proposed methodology is applied to the actual model to verify its effectiveness. The design of a two-speed transmission with multiple operating conditions and constraints without complicated optimization algorithms can be optimized.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.18 no.2
• /
• pp.153-158
• /
• 2005

Recently, as the feasibility study shows that trans-Korea railway and trans-continental railway are advantageous, interest in high-speed railway system is increasing. Because railway vehicle is environment-friendly and safe compared with airplane and ship, its market-sharing increases gradually. KHST(Korean High Speed Train) has been developed by KRRI (Korea Railroad Research Institute) for last 6 years to satisfy the need. An electric railway system is composed of high-tech subsystems, among which main electric equipment such as transformers and converter are critical components determining the performance of rolling stock. We developed a measurement system for on-line test and evaluation of performances of KHST. The measurement system is composed of software part and hardware part. Perfect interface between multi-users is possible. A now method to measure temperature was applied to the measurement system. By using the system, fault diagnosis and performance evaluation of electric equipment in Korean High Speed Train was conducted during test running.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2006.05a
• /
• pp.272-277
• /
• 2006

High speed electric trains have nonlinear loads including converters and inverters for the contol synchronous motors. Harmonic field measurements have shown that the harmonic contents of a waveform varies with time. Direct application of the harmonic assessment to the snapshot measurements would result in ambiguous conclusions depending on which instant is sampled. A cumulative probablistic approach is the most commonly used method to solve time varying harmonics. This paper provides an in depth analysis on harmonics field measurement of the high speed electric train loads, harmonics assessment by the international harmonic standards IEC 61000-3-6 and IEEE std. 519-1992, and harmonics simulation using EDSA program for the case study.

• Proceedings of the KSR Conference
• /
• 2002.05a
• /
• pp.431-436
• /
• 2002

Train driving should be satisfied to run fixed distance within given time, and it is desirable to minimize energy consumption. Minimizing energy consumption depends on the train operation modes by driver or automatic operation. In this article, an optimal operation to minimize energy consumption by changing modes of train operation by a driver is investigated. First, powering model, braking model and consumed energy calculation model are introduced by using Matlab software. The accuracy of the model established by simulation is compared with the real experimental data, which is obtained from an authorized institution. Second, several simulations under a variety of operations in the ideal track are executed, and then the optimal pattern of train driving is found.

• Proceedings of the KSR Conference
• /
• 2004.10a
• /
• pp.1266-1271
• /
• 2004

AT-PASS(Access Train-Portable Access Signal alarm System) which is used at railroad sideway has an important effect upon geography. Especially, it is used at railroad which is a particular condition, tunnel, curve sections and electric car line sections. Therefore, this paper investigated an affection though field test of railroad which is a particular condition.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.20 no.1
• /
• pp.8-13
• /
• 2012

In this paper, Hybrid Electric Vehicle is directly designed and manufactured for base study of HEV's system and Green Car. Foundation design consists of power train design and the frame design. The power train concept includes motor, engine, generator and battery. And the concept of the frame is the single-seat of this self-made HEV. A frame installed in hybrid system contains suspension, steering wheel, seat, accelerating pedal, brake pedal, clutch handle and various chassis parts with bearings. Electromagnetic clutch is equipped to transmit engine power to drive axle. The control algorism make using LabVIEW to control of an engine and a motor depending on drive condition. A parallel type hybrid system is manufactured to control operation of a motor and an engine depending on vehicle speed.

• Proceedings of the KSR Conference
• /
• 2005.11a
• /
• pp.699-704
• /
• 2005

In the station of the railway and the subway various illumination equipment and a general power equipment for a passenger convenience, the signal equipment and the communication equipment which is necessary to the train operation provided. At the all of like this equipment from the electric room which is established in each station by changing from high voltage to low voltage and it supplies from the illumination transformer, the power transformer and the signal transformer. If it supplies to the equipment from the high voltage to the low voltage, it must be established to contact protection device in between the high voltage coil and the low voltage coil. Also it must do the grounding faulting device at the low voltage lines, the earthing devices at apparatus for the protection of an electric shock and an electric fire by the electric relation law. Compared the related regulations between the facilities which require protective functions such as grounding fault or earthing in public utilities like subway stations, and the facilities which do not require line earthing or protective functions such as electricity supplied for signalling the train. Also, will describe a countermeasure for the accident from a grounding fault.

• Journal of Electrical Engineering and Technology
• /
• v.13 no.1
• /
• pp.451-459
• /
• 2018

This work presents an approach for modeling of electric vehicle considering the vehicle dynamics, drive train, rotational wheel and load dynamics. The system is composed of IPMSM (Interior Permanent Magnet Synchronous Motor) coupled with the wheels through a drive train. Generally, IPMSM is controlled by ordinary PID controllers. Performance of the ordinary PID controller is not satisfactory owing to the difficulties of optimal gain selections. To overcome this problem, a new type of fuzzy logic gain tuner for PID controllers of IPMSM is required. Therefore, in this paper fuzzy logic based gain tuning method for PID controller is proposed and compared with some previous control techniques for the better performance of electric vehicle with an optimal balance of acceleration, speed, travelling range, improved controller quality and response. The model was developed in MATLAB/Simulink, simulations were carried out and results were observed. The simulation results have proved that the proposed control system works well to remove the transient oscillations and assure better system response in all conditions.