• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 A
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• pp.319-321
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• 1998

Some design technologies of AC traction motor for rolling stocks are presented. AC Traction motors for rolling stocks are operated in worst conditions such as frequent mechanical vibrations, compact design with limited mounting space, severe thermal stress at outside, driven with nonsinusoidal voltage waveform inverters, and so on. Therefore, design procedures must be carefully investigated in the viewpoint of theoritically and practical use. Design procedure contains, the motor size determination, electromagnetic circuit design, insulation system design, vibrations and thermal expansion of rotor bars, temperature rise, as well as output characteristics.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 B
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• pp.1132-1134
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• 2003

This paper presents the realization of the vector control for AC servo motor using a high performance DSP, TMX320F2812. This DSP has some special peripheral circuits to drive a AC Servo motor as AD converter, QEP and so on. It makes us reduce the time of developing a control system and also can be simple size controller. The vector control algorithm for instantaneous torque control and SVPWM algorithm by offset voltage methods is adopted and we got the satisfactory results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.1047-1050
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• 1993

Recently, AC servo motor has expanded its application areas the to the development of the power semi-conductor and control technology. But it has large torque ripple for its nonlinear characteristics and phase commutaion. In this paper, we proposed the switching angle overlapping method, and current control using tracking method in order to generate the constant torque of AC servo motor that has the trapezoidal back e.m.f. It is compared the these types of control method with the characteristics through simulation. We show that these methods lead the torque ripple to reduce and makes the position and speed characterlistics improved effectively. Also we prove that current control using tracking method is the best way to reduce torque ripple among the these types of control method.

• 전기학회논문지P
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• 제67권4호
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• pp.191-199
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• 2018

The harmonic reduction method of ac motor drive, ACL and DCL were commonly used, but the current distortion ratio was only 35%, thus the several different types of filters as BBHF(broad band harmonic filter), HHF(hybrid harmonic filter), NHHF(new hybrid harmonic filter) have been developed to satisfy the IEEE Std. 519 harmonic limitation. However, these filters had been limited marketability due to cost and size problems. This study suggests the methods to reduce cost and size of the harmonic filter including topologies, besides we discussed simulation results of the power system with regard to the implementation and performance of the filters.

• Journal of Advanced Marine Engineering and Technology
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• 제40권4호
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• pp.348-352
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• 2016

본 논문은 적정 전압 여자를 적용한 스위치드 릴럭턴스 전동기의 효율 개선에 대하여 기술한다. 세탁기와 같이 적용 속도에 큰 차이가 있는 부하의 경우 일정한 직류링크전압으로는 효율 개선에 어려움이 있다. 저속운전영역에서 과도한 직류전압의 영향을 줄이기 위해 보통 사용되고 있는 구동회로내의 다이오드 정류기 대신 SCR을 사용한 AC-DC 컨버터가 SRM 드라이버에 포함된다. AC-DC 컨버터는 저속에 알맞은 적정한 여자전압을 공급한다. 실험결과를 통하여 저속영역에서 효율이 개선됨을 확인하였다.

• 전기학회논문지
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• 제56권9호
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• pp.1571-1576
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• 2007

This report describes the analytical characteristic of sinewave air gap flux density for the brushless AC motor with surface permanent magnet. The analysis of sinewave air gap flux density is the key to expect the performance of back EMF for the design of brushless AC motor. The numerical analysis and FEM analysis are performed to adopt radial and parallel flux magnetization of magnet on the rotor. And it is also executed to vary the magnet arc angle and arc radius for the condition of constant and non constant air gap. This report is focused on the characteristic of sinewave air gap flux density for permanent magnet of surface brushless AC motor. This results also have more reliable data against the previous paper which had the representative numerical analysis of air gap flux density[1][2].

• 전력전자학회:학술대회논문집
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• 전력전자학회 1999년도 전력전자학술대회 논문집
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• pp.14-17
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• 1999

This paper describes the controller for the improving speed control the AC servo motor. The microprocessor provides an output to the difference in command. The servo system improves the characteristics of speed control. When the motor is running at the same speed as set by the reference signal, the speed encoder also provides a signal the same frequency. Thus, the microprocessor controlled digital techniques enable to realize the flexible performance and control which was possible with time constant. We can know that PI control using neural networks by 80196 can control efficiently speed of AC Servo motor. Finally experimental results prove excellent performance of this control system. The system can be adaptable to CNC machine.

• Journal of Magnetics
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• 제19권3호
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• pp.282-290
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• 2014

This paper discusses the development of a 3.5 kW switched reluctance motor (SRM)-based electric air-conditioning (AC) compressor, focusing primarily on the design aspects of the SRM and the integrated controller. In addition to the increased price of rare-earth magnets, SRM's operation capability at high speed and high temperature makes the SRM a viable alternative to the permanent magnet motor for electrically driven automotive air conditioning compressors. A compact and energy efficient scroll compressor is designed and constructed. Two feasible SRM topologies are considered, in terms of efficiency, torque ripple, and acoustic noise. Compact drive electronics are designed and employed to drive the SRM-based compressor. The static and dynamic performance is validated by simulation and experiment.

• 조명전기설비학회논문지
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• 제22권3호
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• pp.79-87
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• 2008

This paper presents a simple circuit topology of the auxiliary active quasi-resonant DC link snubber-assisted three phase voltage source soft-switching inverter for small scale PM motor drive applications. The pulse processing drive circuit interface and its soft-switching operation are discussed from an experimental point of view. Moreover, its conductive noise is measured and evaluated for electrical AC servo motor drive as compared with that of the conventional hard switching inverter.

• Journal of Electrical Engineering and Technology
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• 제12권3호
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• pp.1090-1100
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• 2017

This paper presents the comparison of starting current characteristics of a three-phase induction motor fed by two types of soft starters. The first soft starter under investigation is a conventional AC voltage controller on the basis of a phase-control technique. The other is the proposed asynchronous PWM AC chopper which is developed from the conventional synchronous PWM AC chopper. In this paper, the proposed asynchronous PWM AC chopper control scheme is developed by generating only two asynchronous PWM signals for a three-phase main power circuit (6 switching devices) from a single voltage control signal which is compared with a single sawtooth carrier signal. By this approach, the PWM signals are independent and easy to implement since the PWM signals do not need to be synchronized with a three-phase voltage source. Details of both soft starters are discussed. The experimental and simulation results of the starting currents are shown. It is found that the asynchronous PWM AC chopper efficiently works as a suitable soft starter for the three-phase induction motor due to that the starting currents are reduced and are sinusoidal with less harmonic contents, when being compared with the starting current waveforms using the conventional phase-control starting technique. Also the proposed soft starter offers low starting electromagnetic torque pulsation.