• 한국조명전기설비학회지:조명전기설비
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• 제5권1호
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• pp.46-56
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• 1991

본 연구는 최근 AC서보 구동용으로 각광 받고있는 영구자석 동기전동기의 속도제어기를 자속제어기법에 의한 PWM인버터로 구현하여 최대 토오크 감도운전이 되도록 하는데 있다. 회전자의 위치 및 속도 검출기로서는 레졸버 및 레졸버-디지탈변환기(RDC)를 통해 디지털값의 위치 및 속도정보로 변환한다. 이것을 정보로하여 자속 기준기법에 의한 토오크분 전류를 항상 영구자석의 자계에 직교가 되도록하여 최대토오크 운전이 되도록 한다. 또한 제안한 제어이론으로 정현파 PWM인버터를 실현시키고 부하토오크에 대한 보상방법으로 고정자 전류를 제어기측에 궤환시켜 정상상태 특성을 나타내었다. 이와같은 제어이론을 시뮬레이션과 실험을 통하여 얻은 고정자 전류 및 속도응답 특성 등 영구자석 동기전동기의 동 특성을 검토하여 정상상태하에서 운전 특성이 개선된 결과를 제시하였다.

• Journal of Electrical Engineering and Technology
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• 제2권1호
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• pp.55-60
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• 2007

This paper proposes a hydraulic pump system that uses a variable speed SR drive and constant capacity pump. For the design of the SRM (Switched Reluctance Motor) and digital controller, base speed and rating torque are determined from the mechanical specifications of the hydraulic pump. In order to minimize the power consumption during the maintaining of preset oil-pressure, the pressure control system changes the maximum oil-pressure band and flow rate according to the motor speed. The DSP control system adjusts the oil-pressure and the speed of the SRM from the pressure sensor signal, due to conservation of power consumption by the hydraulic pump. A 2.2Kw, 12/8 pole SR motor and DSP based digital controller are designed and tested with experimental set-up. The test results indicate that the system has some good features such as high efficiency and rapid response characteristics.

• 조명전기설비학회논문지
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• 제23권10호
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• pp.59-68
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• 2009

유도전동기의 벡터제어는 고성능 적용에서 광범위하게 사용되고 있다. 그러나 이러한 드라이브 성능은 파라미터 변동에 의한 동조는 여전히 한계가 있다. 다양한 속도영역에서 운전하기 위하여 종래에는 PI과 같은 제어기를 보통 사용하였다. 이러한 제어기들은 이상적인 벡터제어 조건에서 광범위한 운전에 대하여 제한된 양호한 성능을 나타낸다. 본 논문은 다중 적응 제어기를 사용하여 유도전동기 드라이브의 고성능 제어를 제시한다. 이 제어기는 FAM(Fuzzy Adaptation Mechanism)에 의 해 속도제어, MFC(Model Reference Adaptive Fuzzy Control)에 의해 전류제어 그리고 ANN을 이용하여 속도추정을 수행한다. 제시한 제어 알고리즘은 FAD MFC및 ANN 제어기를 사용하여 유도전동기 드라이브 시스템에 적용한다. 제시한 제어기의 성능은 유도전동기의 파라미터를 사용하여 다양한 동작조건에서 해석으로 평가한다. 또한, 본 논문은 제어기의 효용성을 입증하기 위하여 해석결과를 제시한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 하계종합학술대회 논문집
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• pp.579-582
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• 1989

The air-cooled waterwheel generator has a fan connected to waterwheel shaft or motor driven fan or fans. The fans are operated at constant speed, constant input, regardless of generator loss which is varied according to generator output and coolant the perature. Energy savings may he possible if the cooling air flow is controlled according to generato output and air temperature depending on season. The simulation and experience have been done on the 22.6 KVA Waterwheel generator by using AC variable speed drive. The results gave us los cut of generator.

• 한국정밀공학회지
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• 제27권9호
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• pp.43-51
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• 2010

Speed, accuracy and smoothness are the important properties of pan-tilt camera. In the case of a high ratio zoom lens system, low vibration characteristic is a crucial point in driving pan-tilt mechanism. In this paper, a novel micro-stepping controller with a function of reducing vibration was designed using field programmable gate arrays (FPGA) technology for high zoom ratio pan-tilt camera. The proposed variable reference current (VRC) control scheme reduces vibration decently and optimizing coil current in order to prevent the step motor from occurring missing steps. By employing VRC control scheme, the vibration in low speed could be significantly minimized. The proposed controller can also make very high speed of 378kpps micro-step driving, and increase maximum acceleration in motion profiles.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 B
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• pp.684-686
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• 2000

Switched reluctance motor(SRM) has the advantages of simple structure, low rotor inertia. and high efficiency. However position sensor is essential in SRM in order to synchronize the phase excitation to the rotor position. The position sensors increase the cost of drive system and tend to reduce system reliability. This paper investigates the speed control of sensorless SRM in which the phase current and change rate are utilized in position decision, and the period of dwell angle is variable by compensating the rotor angle for speed control. The proposed system consists of position decision. phase locked loop controller, switching angle controller and inverter. The performances in the proposed system are verified through the experiment.

• Journal of KIEE
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• 제11권1호
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• pp.62-68
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• 2001

In this paper it is proposed an advanced modified sliding mode control of a rotor field oriented control of induction motor. The application of this unconventional control has very good results, such as disturbance rejection and nice dynamic properties. Stability can be guaranteed even in the worst situation. A conventional "sliding mode" controller is characterised by fast switching control signal, which causes the chattering of the drive system. To overcome this problem, a modified law is used, by introducing a hysteresis band and a continuous control, which modifies the conventional law. The control is accomplished with dual TMS320C44 floating-point digital signal processor. The validity of the proposed method was verified by experiment on the propulsion system simulator, used for the development of Korean High-Speed Railway Train(KHSRT).in(KHSRT).

• 전력전자학회:학술대회논문집
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• 전력전자학회 2007년도 하계학술대회 논문집
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• pp.391-393
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• 2007

The rotor speed and flux information is most important in the vector control. The accuracy of flux observers for induction machine inherently depends on parameter sensitivity. The control strategy is using online flux observer for flux estimation. In the proposed system, the speed control characteristics using a online flux observer control isn't affected by a load torque parameter disturbance. Simulation results are presented to prove the effectiveness of the adaptive sliding mode controller for the drive variable load of induction motor.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.233-233
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• 2000

Direct torque control (DTC) scheme provides a very quick torque response without the complex field-orientation block and inner current regulation loop. DTC is known as an appropriate scheme for high power induction motet drives because it can be used at lower switching frequency. There are two major drawbacks with the application of DTC schemes : one is large current harmonics due to flux drooping in a low speed range, the other is that the inverter switching frequency is varying according to motor parameters and operating speed. Switching devices in the power electronics drives should be supported for relatively high switching frequency. In this paper, a P-type fuzzy controller to realize the variable switching sector scheme and a PID-type fuzzy switching frequency regulator are adopted. A meaningful contribution of this paper is to propose a simple realization scheme of the fuzzy switching frequency regulator. Simulation results show the effectiveness of those propositions.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2004년도 전력전자학술대회 논문집(2)
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• pp.988-991
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• 2004

In the paper, a four-phase 16/12 structure Switched Reluctance motor drive is presented. The construction of the stator and the rotor in the motor, the scheme of the rotor position detector and the main circuit of the power converter are described. The comparison of the four-phase 16/12 motor and the four-phase 8/6 motor and the comparison of the four-phase 16/12 motor and the three-phase 12/8 motor are made. In the controller, the PWM control variable-speed control, the commutation control, the four quadrants control, the overvoltage protection, the over current protection and the under voltage protection could be achieved. Tested results of the developed prototype are made.