• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 F
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• pp.2628-2631
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• 1999

One of the limitations of conventional ASCI for high-power induction motor drives is the high voltage that is produced in the commutation capacitors during the current commutation from one phase to another. Since the capacitor voltage appears directly on the semiconductor components, it increases their required voltage ratings. Also, the high-voltage spikes generated at the motor terminals may cause damage to the motor insulation. And we investigated how de input power is increased or decreased according to size of de link inductor. In this paper, de link inductor and clamping capacitor in GTO inverter suitable for induction motor drives are propose through experiment.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집A
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• pp.641-645
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• 2001

Storage drives for mobile devices, such as laptop computers or PDAs, are changing now. The data density of storage drives is becoming higher and sizes of those are becoming smaller and thinner. Spindle motors for rotating disk are also becoming smaller and thinner. But, large torque is required to reduce seek time. In this research, inner rotor type spindle motor suitable for thin thickness has been developed. Rotor and stator are optimized structurally for large torque performance with small size. Especially, high vibration and shock performances, which are essential to mobile devices, are analyzed in detail.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 추계학술대회 논문집
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• pp.406-409
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• 1997

An economical 4-axis CNC controller employing step motors is designed and implemented in this paper. By using the inherent ability of holding position of the motor, the CNC controller uses open-loop control for removing trajectory error and for a simple hardware. Each drive of axis has an 8-bit microprocessor 89C52 and a PC controls the axes and pendant by means of RS232C serial communication. Backlash is also compensated at the axis controller. While compensating the backlash, the feed rate becomes zero in order to minimize trajectory error. The trajectories of 16ms interval are computed on PC and are sent to motor drives. In the drives, the trajectories are linearly interpolated for 2ms interval. The developed CNC does not require add-on specific motion card on PC. From the experimental results, the validity of the CNC controller based on step motor is proved.

• Journal of Electrical Engineering and Technology
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• 제8권1호
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• pp.110-117
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• 2013

Maximum Torque Per Amp (MTPA) control for induction motor drives seeks to achieve a desired torque with the minimum possible stator current. This is favorable in terms of inverter operation and nearly optimal in terms of motor efficiency. However, rotor resistance variation can cause significant performance degradation. This work demonstrates that existing MTPA controls perform sub-optimally as temperature varies. An adaptive MTPA control strategy is proposed that always achieves optimal performance without exhibiting hunting phenomenon regardless of rotor temperature. The proposed control is experimentally shown to accurately achieve the desired torque.

• Journal of Electrical Engineering and Technology
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• 제9권1호
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• pp.231-238
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• 2014

Adaptive Maximum Torque Per Amp (Adaptive MTPA) control for induction motor drives seeks to achieve a desired torque with the minimum possible stator current regardless of operating points. This is favorable in terms of inverter operation and nearly optimal in terms of motor efficiency. However, the Adaptive MTPA control was validated only from the viewpoint of tracking a desired torque and was not shown that the desired torque is achieved with minimum possible stator current. This work experimentally demonstrates that optimal condition for Adaptive Maximum Torque Per Amp Control Strategy is achieved regardless of rotor resistance variation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 학술대회 논문집 전문대학교육위원
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• pp.108-112
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• 2001

Vector control schemes are used in inverter-fed induction motor drives to obtain high performance. Crucial to the success of the vector control scheme is the knowledge of the instantaneous position of the rotor flux. However, the position of the rotor flux change with temperature and magnetic saturation of the motor. This variation cause deterioration of both steady state and dynamic operation of the motor drives. Performance degradation is in the form of input-output torque nonlinearity and saturation of the motor. Analytic expressions are derived to evaluate the effects due to parameter sensitivity.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 B
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• pp.991-993
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• 2000

The paper presents the software control of a brush-less do motor with parameter identification. Not only speed and current controls but also a real-time identification of the motor parameters can be implemented by software using the digital signal processor TMS320F240. The DSP Controller TMS320F240 from Texas Instruments is suitable for a wide range of motor drives TMS320F240 provides a single chip solution by integrating on-chip not only a high computational power but also all the peripherals necessary for electric motor control. This new family of DSPs enables single chip, cost effective, modular and increased performance solutions for BLDC drives. The present paper describes how a speed controlled brushless DC drive can be implemented using TMS320F240 and what kind of results can be achieved.

• 전기학회논문지P
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• 제53권2호
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• pp.51-57
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• 2004

Vector control schemes are used in inverter-fed induction motor drives to obtain high performance. Crucial to the success of the vector control scheme is the knowledge of the instantaneous position of the rotor flux. However, the position of the rotor flux change with temperature and magnetic saturation of the motor. This variation cause deterioration of both steady state and dynamic operation of the motor drives. Performance degradation is in the form of input-output torque nonlinearity and saturation of the motor. Analytic expressions are derived to evaluate the effects due to parameter sensitivity. Also, dynamic response is shown by speed command with the variation of stator and rotor resistance.

• Journal of Electrical Engineering and Technology
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• 제6권5호
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• pp.626-633
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• 2011

This paper presents a novel maximum efficiency control scheme for convergence improvement in stator-flux-oriented induction motor drives. Three input powers are calculated at three different flux levels, respectively. A quadratic curve is obtained using the quadratic interpolation method using the three points. The flux level at the lowest point of the interpolated curve is calculated, which is not the real minimum input power of the motor, but an estimated one. Hence, the quadratic interpolations are repeated with three new points chosen using the selection method for new points for refitting until the convergence criteria are satisfied. The proposed method is verified by simulation results.

• 전력전자학회논문지
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• 제7권3호
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• pp.224-236
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• 2002

PWM기법의 성능을 비교하고 있다. 랜덤 펄스 위치 PWM기법은 2상 또는 3상 펄스들을 변조 구간내의 임의의 위치에 랜덤하게 배치하고 인버터 스위칭에 의하여 고조파의 스펙트럼을 광역화하는 RPWM기법이다. 시뮬레이션과 실험에 의하여 인버터 출력 전압의 고조파 스펙트럼과 맥동 전류 파형 그리고 모터의 가청 스위칭 소음의 저감 효과를 비교 검토하였다. 스위칭 손실 및 연산시간 그리고 구현의 용이성에서 3상 RPWM보다는 2상 RPWM이 양호하며, 고조파의 광대역화 측면에서는 3상 RPWM이 보다 좋은 성능을 지니고 있음을 알 수 있었다. 또한 가청 스위칭 소음저감은 2상 RPWM과 3상 RPWM이 거의 유사한 성능을 갖고 있음이 확인되었다.