• Journal of Advanced Marine Engineering and Technology
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• 제27권1호
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• pp.100-107
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• 2003

This study was to control magnetic field orientation-typed sensorless vector control by applying the theory of a rotor flux observer to drive an induction motor. This research suggested a new speed estimation method that estimates speed with the rotor flux obtained by using a flux observer and the variable of state current detected by a current sensor without a speed sensor. Because the speed estimation method is independent from the motor constants, it is not necessary to control the gain of the parameters and the algorithm is simple. In the findings of the study, the researcher was convinced of the control function and the possibility of realization in the simulation experiment of sensorless vector control system by using DSP(Digital Signal Prosessor).

• 전기전자학회논문지
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• 제24권4호
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• pp.954-960
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• 2020

본 논문은 단상 영구자석 동기전동기의 속도 가변형 비례공진 전류제어 기법을 제안한다. 단상 영구자석 동기전동기는 전자기적 특성상 고정자 전류와 역기전력의 위상차에 따른 부토크 및 영토크가 발생하며 센서리스 운전 시 낮은 고정자 저항과 인덕턴스로 인해 과전류 제한이 필요하다. 이러한 조건하에서 전류제어를 위해 3상 교류 전동기에 사용되는 벡터 제어를 이용할 경우, 좌표변환, 역좌표변환 및 가상의 dq축 성분을 생성하는 과정이 필요하다. 하지만, 단상 영구자석 동기전동기의 자기적 특성을 고려하여 제안한 속도 가변형 비례공진 전류제어 기법은 3상 교류 전동기에 사용되는 좌표변환 과정이 필요하지 않다. 본 논문에서는 가변 비례공진 전류제어 기법을 이용하여 안정적인 기동 성능을 확인하며 일정 속도 도달 시 위치 센서 없이 단상 영구자석 동기전동기의 수학적 모델 기반 센서리스 제어로 제안한 전류제어 기법의 효용성을 다수의 실험을 통해 검증하였다.

• 전기학회논문지P
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• 제51권4호
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• pp.219-221
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• 2002

This paper presents an electric scooter development using blushless DC motor. In recent scooters was to develop for sport leisure and short transportation. Most of scooter are used petroleum gas. This gas scooter has disadvantage to pollute the air. Some of scooters have developed by DC motor which require a brush. However brushless motors have higher maximum speed and greater capacity, save maintenance labour and produce less noise. There is also greater freedom in planing the usage of brushless motors. In this paper we develop an electric scooter driving BLDC motor for design smart system and control speed of scooter with current reference signal to apply voltage to motor by means of three phase inverter. Using accelerator device we generate current reference to control speed and send the current to a MICOM by A/D converter. This MICOM produces the voltage signal and hall sensors signal and PWM controller drive three phase inverter to minimize error between the reference and an actual current.

• Journal of Power Electronics
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• 제11권5호
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• pp.726-733
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• 2011

BLDC Motors are widely used in various speed control applications due to their ease of control and low cost. Generally, the unipolar PWM method is used for speed control applications. However, the unipolar PWM method has a current spike problem in the braking operation which can be a problem in speed reversal which generally happens in position control applications. However, the current spike problem can be solved by the conventional bipolar PWM method. Although the current spike problem can be solved, the conventional bipolar PWM method has the problem of a large current ripple. In this paper, a novel bipolar PWM method is proposed to solve this problem. The current ripple and the current spike problems are analyzed in this paper for the unipolar and bipolar PWM methods. At last, the merits of the proposed bipolar PWM method are proven by experiment.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2004년도 춘계학술대회 학술발표 논문집 제14권 제1호
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• pp.153-156
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• 2004

This Paper deals with speed control of DC servo motor using a Fuzzy-Sliding observer. Speed sensor detect a speed of rotor continuously. But It have a limit as a driving speed to detect speed precisely. So it is problem to improve the performance of the driving system To solve the problem, it is studied to detect a speed of DC motor without sensor In particular, study on the method to estimate the speed using the observer is performed a lot. In this parer, the gain of the observer is properly set up using the fuzzy control and sliding observer that have a superior transient characteristic and is easy to implement compared the exist ing method is designed. It estimate the derivative of the armature current directly using the armature current measured in the DC motor. It estimate the speed of the rotor using the differentiation. It is Proposed speed sensor less control method using the estimated speed. Optimal gain of Luenberger observer is set up using the fuzzy control and adapted speed control of DC servo motor. It is proved excellence and feasibility of the presented observer from the comparison tested a case with a speed sensor and a case without a speed sensor which used a highly efficient drive and 200W DC servo motor start ing system.

• Journal of Advanced Marine Engineering and Technology
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• 제27권4호
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• pp.503-510
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• 2003

A new method of induction motor drive, which requires neither shaft encoder nor speed estimator, is presented. The proposed scheme is based on decreasing current gap between a numerical model and an actual motor. By supplying the identical instantaneous voltage to both model and motor in the direction of reducing the current difference. the rotor approaches to the model speed. that is. reference value. The indirect field orientation algorithm is employed for tracking the model currents. The performance of induction motor drives without speed sensor is generally characteristic of poorness at very low speed. However, in this system, it is possible to obtain good speed response in the extreme low speed range.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2009년도 추계학술대회
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• pp.510-513
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• 2009

In this paper, a novel speed control algorithm of DC motors is presented. The key contribution here is a simple speed controller only with speed feedback and without an inner current control loop. This is possible by adjusting the reference speed based on a certain rule. Therefore, the proposed speed controller here becomes simpler while maintaining the control performance. Moreover, with the proposed controller, the system response can be tuned with less complexity. This proposed control method is investigated both mathematically and experimentally.

• Journal of Power Electronics
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• 제12권1호
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• pp.58-66
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• 2012

SRMs(Switched Reluctance Motors) are much interested in high speed applications due to the mechanical robustness, simple structure and high efficiency. In spite of many advantages of SRMs, a higher torque ripple discourages the adoption of SRMs in a high speed application. This paper presents a simple negative torque of tail current compensation scheme using a modified TSF(Torque Sharing Function) for the high speed SRMs. Because of the short commutation in the high speed region, the negative torque from the tail current makes the high torque ripple. In order to reduce and compensate the negative torque from tail current, the proposed control scheme produces an additional compensating torque with a reference torque in the active phase winding. And the compensating value is dependent on the tail current of the inactive phase winding. Furthermore, the switching signals of the outgoing phase are fully turned off to restrict the extended tail current, and the torque error of the outgoing phase is compensated by the incoming phase. The proposed modified TSF control scheme is verified by the computer simulations with 30,000[rpm] high speed 4/2 SRM. The simulation and experimental results show the effectiveness of the proposed control scheme.

• Journal of Electrical Engineering and Technology
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• 제10권5호
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• pp.2052-2056
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• 2015

This Paper analyzes the characteristics of the WRSM in high-speed operation range. To verify the control characteritics of various WRSM models, the relative position of the central point of current limit circle and voltage limit ellipse is defined as M value and 3 models according to M_max value are designed through inductance change. Through the designed models, the current control method of 3-variables control for maximum power especially in high-speed operation range is presented.

• 한국기계가공학회지
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• 제12권4호
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• pp.16-21
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• 2013

This paper presents a DC link voltage control method to reduce the ripple current and the switching loss in the sinusoidal current drive system for the wide-speed range PMSM. The DC link voltage of the three phase inverter in the sinusoidal current drive system is designed by the back-EMF voltage at maximum speed of the PMSM. In general, the drive systems have used the constant DC link voltage without reference to the motor speed. The current ripple causes hysteresis loss and makes noise. In addition, the switching loss on the inverter increases in proportion to the rise in the DC link voltage. In this paper, we propose the variable DC link voltage control method to reduce the current ripple in the PMSM drive system. We show reduction effect of the current repple and the switching loss through simulation results.