• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.500-504
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• 1997

Current source inverter drives of auto sequentially commutated type are very popular in high power applications, because of simple power circuit configuration with four quadrant operation. But the six-step current output create harmonic problems and the input power factor of such a drive is not always good. In this respect pulse width modulated drives using gate turn off thyristors ( GTO ) are finding application, especially in traction drives. However the switching and snubber loses of a GTO do not permit the inverter switching frequency go beyond a few hundred hertz.This will again introduce low frequency harmonic problems. Multi level inverters of the 3-level and 5-level can be considered as an alternative to overcome the low switching frequency harmonic problem of the 2-level GTO inverters. But with multi level inverters the complexity of the power circuit increases. In this paper a combination of multi level ( 2-level and 3-level ) inverters and multi phase induction motor ( 3-phase and 6-phase) configurations are presented for high power VSI drives for traction applications with reduced inverter switching frequency requirements coupled with reduced voltage rating for the power switch.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 A
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• pp.474-476
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• 1999

This paper presents the vector control of induction motor for traction drives. Especially, the PWM mode control method is well described to be selected as the change of speed to meet the wide speed range of the traction motor. Asynchronous space vector PWM mode and synchronous one pulse mode are basically used under the full speed range with the overmodulation PWM mode for the soft transfer between them. The validity of this proposed control scheme is verified with the simulation results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 A
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• pp.427-429
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• 1999

According to the development of power electronic element(GTO. IGBT) and material for electrical machines(permanent magnet. super conductor), the technology for electrical machines is now a day rapidly developing. Here with, a novel electrical machine, based on the new conception of transverse flux configuration leads to a considerable increase in power density and enables simultaneously high efficiency. The transverse flux machine with PM excitation will be applied to gearless direct drives for railway traction system. The designed and measured performance of transverse machine for railway traction system revealed a great potential of system improvements to reduce linear motor mass.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.220-224
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• 2005

EMU(Electric Multiple Unit) operated in local area is mostly consist of moving system on the rail and the traction motor drives the gear and wheel with the mechanical propulsion force. Most of countries are interested in Magnetic Levitation Vehicle for the transportation system on next generation and they have been studying about it continuously. Thus this paper is studied the Linear Induction Motor as the propulsion equipment of Magnetic Levitation Vehicle

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• 제3B권1호
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• pp.52-58
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• 2003

The application of a sliding mode control for improving the dynamic response of an induction motor based speed control system is presented in this paper and provides attractive features, such as fast response, good transient performance, and insensitivity to variations in plant parameters and external disturbance. However, chattering is a difficult problem for which the sliding mode control is a popular solution. This paper presents a new fuzzy-sliding mode controller for a sensorless vector-controlled induction motor servo system to practically eliminate the chattering problem for traction applications. A DSP based implementation of the speed control system is employed. Experimental results are presented using a propulsion system simulator. The performance of the drive is shown to be practically free from chattering.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 춘계전력전자학술대회 논문집(2)
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• pp.860-865
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• 2003

Recently, SRMs are used in automobiles for power assistant steering, accessory motion control and traction drives. Especially in the motion control and traction drives, safety and efficiency are of paramount important. The paper describes the essential elements, faced in designing and constructing drive circuits for a switched reluctance motor for automobiles. These converters will be referred to as energy efficient C-dump converter and modified C-dump converter Energy efficient C-dump converter topology eliminate all the disadvantages of the C-dump converter without sacrificing its attractive features, and also provide some additional advantages that have lower number of power devices, full regenerative capability, free-wheeling in chopping or PWM mode, simple control strategy, and faster demagnetization during commutation. The experiments are peformed to verify the capability of proposed control method on 6/4 salient type SRM.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2000년도 전력전자학술대회 논문집
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• pp.49-52
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• 2000

The purpose of this paper is to evaluate practical advantage in using maximizing efficiency control strategy in induction motor drives for electric vehicles. A maximizing efficiency control strategy consist of a flux estimation with direct field oriented controller is proposed and compared with the general constant flux control strategy. The comparison is carried out by experimental results and simulation of the behavior of electric vehicles. Results are included to show the effectiveness of the proposed strategy in the electric vehicle applications.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 B
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• pp.676-684
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• 1992

The advent of inexpensive high power switching devices revived the interest in switched reluctance motor(hereafter referred to as SRM) drives. In the late 60's, the potential of SRM for traction application attracted researchers. Since then the progress in research of the SRM drive has been phenomenal. In this paper, a review of the basic principle of operation of the SRM, currently available converter topologies, the controller requirements and some design considerations are included.

• Journal of Electrical Engineering and Technology
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• 제13권3호
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• pp.1156-1165
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• 2018

This paper presents a detailed realization of direct torque controlled induction motor drive for elevator applications. The drive is controlled according to the well-known space vector modulated direct control scheme (SVM-DTC). As the elevator drives are usually equipped with speed sensors, flux estimation is carried out using a current model where two stator currents are measured and accurate instantaneous rotor speed measurement is used to overcome the need for measuring stator voltages. Speed profiling for a comfortable elevator ride and other supervisory control activities to provide smooth operation are also explained. The drive performance is examined and controllers' parameters are fine-tuned using MATLAB/SIMULINK. The blocks used for flux and torque estimation and control in the offline simulation are compiled for real-time using dSPACE Microlabox. The performance of the drive has been verified experimentally. The results show good performance under transient and steady state conditions.

• Journal of Power Electronics
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• 제16권5호
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• pp.1851-1860
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• 2016

The traction motors in electric multiple unit (EMU) trains are powered by AC-DC-AC converters, and the DC link voltage is generated by single phase PWM converters, with a fluctuation component under twice the frequency of the input catenary AC grid, which causes fluctuations in the motor torque and current. Traditionally, heavy and low-efficiency hardware LC resonant filters parallel in the DC side are adopted to reduce the ripple effect. In this paper, an analytical model of the ripple phenomenon is derived and analyzed in the frequency domain, and a ripple control scheme compensating the slip frequency of rotor vector control systems without a hardware filter is applied to reduce the torque and current ripple amplitude. Then a relatively simple discretization method is chosen to discretize the algorithm with a high discrete accuracy. Simulation and experimental results validate the proposed ripple control strategy.