• 전력전자학회:학술대회논문집
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• 전력전자학회 2004년도 전력전자학술대회 논문집(1)
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• pp.186-189
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• 2004

Switched reluctance machine has much attention because of high efficiency, high power and DC series torque characteristics with a traction drive. But the motor has to have a regenerative mode when it is adopted in an electric vehicle. A current divergence during the regeneration makes difficulties in the control of SRM. This paper proposes a reference current limitation strategy for a stable regeneration based on simulations and experimental tests. The motor is operated with conventional current limit and switching angle control method in motoring mode. Simulations and experiments are executed to verify proposed method.

• 전력전자학회논문지
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• 제8권3호
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• pp.285-291
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• 2003

스위치드 릴럭턴스 전동기는 고출력, 고효율 및 직권전동기 구동특성 등으로 견인구동용으로 주목받고 있다. 그러나 전동기를 4상한 구동하기 위한 발전영역에서 제어는 쉽지 않다. 본 논문은 전류제한법에 의해 안정된 발전제동이 가능한 제어방식을 제안하였다. 전동기 구동시는 기준전류제한방식과 위상각 제어방식으로 속도제어를 행하고, 발전제동모드에서는 상전류가 발산하지 않는 조건을 산정하여서 이 값을 기준전류로 한 전류제한방식을 채택하였다. 시뮬레이션과 실험에 의해 제안한 방식의 타당성을 확인하였다.

• 한국전자통신학회논문지
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• 제5권5호
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• pp.541-546
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• 2010

유연한 로봇팔은 모터에 의해 관절 축을 회전할 때 진동이 발생한다. 유연한 팔이 원하는 각으로 회전하면서 동시에 팔 끝의 진동이 안정화되도록 제어하였다. 본 논문에서 유연한 로봇팔의 동력학은 bernoulli-Euler의 beam이론과 라그란지 방정식을 이용하여 구하였고, 섹터 내부에 연속입력함수를 가진 슬라이딩 섹터이론을 이용하여 히스테리시스 사구간을 가진 비선형 제어기를 제안한다.

• 대한전기학회논문지
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• 제40권2호
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• pp.200-206
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• 1991

In this paper, an output feedback is used to reduce the effect of the vibration in the control of a flexible one-link robot arm. A PD control method with a time varying gain is proposed to improve the performance of the system in tip deflection and settling time for the step reference input. By making the change of feedback gain smoothly, th input torque can be made smooth. When there is a payload with unknown mass, an interpolation method which uses the inrehgrated value of the transient response of the hub angle is proposed for the estimation of teh payload mass. This method can be used when the reference input is known and we can get highly accurate estimate for the unknown payload. It is also demonstrated that flexible one-link arm can be controlled prettry accurately by an output feedback in a noisy environment without knowing the mass of the payload.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2020년도 전력전자학술대회
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• pp.248-250
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• 2020

본 논문은 토크 각 기반 Direct Self Control (DSC) 기법의 매입형 영구자석 동기전동기(Interior Permanent Magnet Synchronous Motor, IPMSM) 고속 운전 방법을 제안한다. DSC 기법은 철도차량용 유도전동기에 처음으로 적용되었으며, 토크 동특성이 우수하고 약자속 영역에서 6-스텝 운전의 구현이 유리한 장점이 있다. 기존 DSC 기법으로 IPMSM을 구동하는 경우 토크 동특성이 우수하지만, 약자속 영역에서 6-스텝 운전의 성능이 떨어지는 단점이 있다. 본 논문에서는 지령 토크 각을 이용한 DSC 기법의 IPMSM 고속 운전 방법을 제안한다. 제안하는 방법의 타당성은 시뮬레이션을 통해 검증한다.

• 수산해양기술연구
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• 제36권1호
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• pp.25-32
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• 2000

A combination steering system was designed to provide the flexibility in controlling the steering wheel in fishing operations of the inshore and coastal fishing vessels. The designed steering system basically is consisted of three driving units, such as a electrically driven hydraulic pump unit with a solenoid control valve, a DC motor driven hydraulic pump unit and a manually driven hydraulic pump unit, and two controllers to provide remote steering on the deck, respectively. The steering torque was measured and analyzed to investigate the dynamic performance of the developed steering system. The steering system showed excellent linearity between the working pressure of cylinder and the torque of rudder post in case of increasing in rudder angle from $5^{\circ} to 35^{\circ}$ that is, the steering torque increased from $10.4 kgf{\cdot}m$ to $105.3 kgf{\cdot}m$ and then the working pressure of cylinder fluctuated from 6.3 kgf/cm super(2) to 16.4 kgf/cm super(2). The steering time of 3.2 sec in remote hydraulic steering by the on/off solenoid valve control was much faster than 13.2 sec in the manual steering by the helmsman and 11.6 sec in the electric steering by a DC motor, and then it was verified that operation of one unit does not affect other units in combination steering system in any way. Furthermore, the developed steering system can be remotely controlled in multiple stations of the deck during the fishing operation and the automatic pilot steering unit can be used to add hydraulic steering.

• Journal of Electrical Engineering and Technology
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• 제1권1호
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• pp.52-57
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• 2006

In this paper, a new 'impedance sensing' method is described. This method overcomes the shortcomings of the impedance sensing method. According to the new method, sensing voltage pulse is applied to the idle phase in the minimum inductance region and the beginning of the increasing inductance region to detect rotor position. The negative torque produced by the sensing voltage pulse can be neglected in the minimum inductance region and the efficiency of SRM is improved. In the minimum inductance region the back electromotive force (EMF) can be neglected. And in the increasing inductance region the EMF opposes the rise of current in the phase, so the position estimation scheme is reliable. Therefore the new 'impedance sensing' method is sufficiently precise even under the high back EMF effect. The adjustment of turn-on angle and turn-off angle is also easy to be realized. The technique is very useful in applications where cost or size is primary concerns, such as electric bicycle drives. Experimental results are presented to verify the proposed method.

• Journal of Yeungnam Medical Science
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• 제4권1호
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• pp.151-156
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• 1987

본 증례는 Angle씨(氏) 2급 2류 부정교합 환자로서 Bioprogressive Mechanism을 적용시켜 양호한 결과를 얻었기에 이에 보고하는 바이며 치료결과는 다음과 같다. 1) 주소인 상하악 전치부 crowding을 해소하였다. 2) 구치부 관계는 Angle씨(氏) classII에서 classI으로 개선되었다. 3) Overbite와 overjet를 기능적으로 해소시킴과 동시에 전치부 torque control에 의한 만족스러운 치축경사도로 개선시켰다.(Photo.5) 4) 치료기간은 1년 11개월이 소모되었다.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제50권11호
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• pp.575-582
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• 2001

This paper presents a calculating method of switching angle for adaptive switched reluctance motor (SRM) drive of a drill. The operation of the SRM is completely characterized by the flux linked by one phase winding which depends only on the current in that same phase winding and the rotor position. An efficiently adaptive SRM drive is possible on appropriately scheduling the commutation angles with accurate rotor position, supplied current value and speed information. An adaptive SRM drive with reduction torque ripple should be controlled by an optimized phase current control along with rotor position. Therefore, we are suggested a computing method of switching turn-on and off angles for adaptationally SRM operation with varied rotor speed and load. To probe the computing method, we have some simulation and experiment, it is shown a good result that can be computing the optimized switching angles for an electric drill motor.

• 제어로봇시스템학회논문지
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• 제15권11호
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• pp.1130-1136
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• 2009

A new control algorithm for the yaw motion control of a unicycle robot has been proposed in this paper. With the increase of life quality, there are various transportation systems such as segway and unicycle robot which provide not only transportation but also amusement. In most of the unicycle robots share the same technology in that the directions of roll and pitch are controlled by the balance controllers, allowing the robots to maintain balance for a long period by continuously moving forward and backward. However, one disadvantage of this technology is that it cannot provide the capability to the robots to avoid obstacles in their path way. This research focuses to provide the yawing function to the unicycle robot and to control the yaw motion to avoid the obstacles as desired. For the control of yawing motion, the yaw angle is adjusted to the inertia generated by the velocity and torque of a yawing motor which is installed in the center axes of the unicycle robot to keep the lateral control simple. Through the real experiments, the effective and robustness of the yawing control algorithm has been demonstrated.