• 제목/요약/키워드: coil constant

검색결과 163건 처리시간 0.023초

3상 가변형 셀프 베어링 스텝모터의 제어 (Control of a 3-Phase VR Type Self-Bearing Step Motor)

  • 김대곤
    • 대한기계학회논문집A
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    • 제25권12호
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    • pp.1974-1980
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    • 2001
  • The control algorithm of a new type self-bearing step motor is presented. The motor actuator is used for both motor and bearing functionality without any redundant coil windings or redundant electromagnets. The self$.$bearing step motor layout and its control method are described. A linearized farce-current-displacement relationship is derived. As the result of the unbalance response approach, the constant torque production is possible fur the supply current regulation algorithm. And even if the bearing functionality is added in the motor functionality, no additional current for bearing functionality is possible, and this leads to minimize the net power loss. Also, the unbalance response shows the independent bearing force and motor torque.

RF-enhanced DC-magnetron Sputtering of Indium Tin Oxide

  • Futagami, Toshiro;Kamei, Masayuki;Yasui, Itaru;Shigesato, Yuzo
    • The Korean Journal of Ceramics
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    • 제7권1호
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    • pp.26-29
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    • 2001
  • Indium tin oxide (ITO) films were deposited on glass substrates at $300^{\circ}C$ in oxygen/argon mixtures by RF-enhanced DC-magnetron sputtering and were compared to those by conventional DC magnetron sputtering. The RF enhancement was performed using a coil above an ITO target. X-ray diffraction measurements revealed that RF-enhanced plasma affected the preferred orientation and the crystallinity of the films. The resistivity of the films prepared by RF-enhanced DC-magnetron sputtering was almost constant at oxygen content lower than 0.3% and then increased sharply with increasing oxygen content. However the resistivity of the films by conventional sputtering has little dependence on the oxygen content. Those results can be explained on the basis of the incorporation of oxygen into the ITO films due to the RF enhancement.

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IPM모터의 턴쇼트 고장 대응운전 알고리즘 : 전력 손실 한계 내에서 최대토크 제어 (Interturn Fault Tolerant Driving Algorithm of IPMSMs : Maximum Torque Control within Power Loss Limit)

  • 임성환;구본관
    • 전기학회논문지
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    • 제67권1호
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    • pp.52-60
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    • 2018
  • The winding of the motor stator coil is broken due to external stress and various factors. If the proper current is not injected when interturn fault(ITF) occurs, the fault can easily be expanded and the motor can be finally destroyed, resulting in many problems with time costs and safety. In this paper, the power loss limit concept, which is the inherent durability of each motor, is applied to secure safety by controlling the total power loss of the motor within the limits. So, we propose an algorithm that can control maximum torque per minimum power loss based on constant torque curve and power loss limit. To verify the proposed method, the simulation and experimental results with an Interior permanent magnet synchronous motor(IPMSM) having an ITF are shown.

여자 방식에 따른 다권선 LDM의 특성 해석 (Characteristics Analysis of multi-separated winding LDM by Excitation Mode)

  • 김재필;백수현;맹인재;우영수;김일남
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 B
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    • pp.804-806
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    • 2001
  • In this paper, by designing ratio width of the permanent magnet versus the stator coil, double excitation LDM with multi-separated winding which is possible to obtain the constant thrust force is proposed. Using Empulse, this paper has explained a various excitation mode to analyze the thrust force of multi-separated winding LDM. The simulation results show single-phase excitation mode have low thrust force ripple.

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부하변동에 대한 바이패스 공조시스템의 특성 (The Characteristics of a Bypass Air Conditioning System for Load Variation)

  • 김보철;신현준;김정엽
    • 설비공학논문집
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    • 제14권3호
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    • pp.240-246
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    • 2002
  • Bypass air conditioning systems are divided into three types; an outdoor air bypass, a mixed air bypass and a return air bypass system. What makes the return air by pass system more effective is that it directs all of moist outdoor air through the cooling coil. The bypass air conditioning system can maintain indoor R.H (Relative Humidity) less than a conventional CAV (Constant Air Volume) air conditioning system by adjusting face and bypass dampers at part load. When a design sensible load (the ratio of sensible load to total sensible load) is 70 percent (at this time, RSHF (Room Sensible Heat Factor) . 0.7), indoor R.H was maintained 59 percent by the return air bypass system, but 65 percent by the conventional CAV air conditioning system (valve control system). The bypass air conditioning system can also improve IAQ (Indoor Air Quality) in many buildings where the number of air change is high.

전공식 콘트롤 밸브 Positioner 용 Magnet Unit의 해석 (An Analysis of Magnet Unit of Electro-Pneumtic Control Valve Positioner)

  • 김성재;김지원;조순철;정선태;유형근;전찬구;고택범
    • 한국자기학회지
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    • 제7권6호
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    • pp.321-326
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    • 1997
  • 유량을 정밀조정하는 콘트롤 밸브의 핵심 부품인 magnet unit를 해석하였다. 유한요소법을 이용하여 자석과 요크가 이루는 자기회로를 분석하여 공극에 흐르는 자속과 코일이 받는 힘을 계산하고 이를 측정치와 비교하였다. 시뮬레이션 결과 공극자장은 3 ~ 5 kOe, 추력상수는 27.5 N/A, 퍼미언스 게수는 22.1 이었으며 측정치와 잘 일치하였다. 또한 시뮬레이션을 통하여 reluctance factor는 1.1 fringing factor는 1.4 임을 알 수 있었다.

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Design of Torsion-typed Smooth Picture Actuator for DLP Projection TV

  • Moon, Yang-Ho
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.564-568
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    • 2006
  • Smooth picture module is operated by vibration to tilt the light from the DMD (digital micro mirror device) of DLP projection TV, which makes the screen of the TV smoother and DMD chip cost lower. To satisfy the vibration characteristics of smooth picture module, it is designed by optimizing moment of inertia, spring constant and damping coefficient, using structural and fluid dynamic simulation that showed a good agreement with experimental data. To reduce the material cost and moment of inertia, engineering plastic is used and the reliability is estimated. A VCM (voice coil motor) type actuator for smooth picture has to satisfy performance requirements such as higher driving force, lower power consumption, and lower cost. The initial design and optimization for VCM was performed using FE analysis. It allowed us to optimize the design of magnetic circuit of the proposed actuator to obtain higher force while maintaining a lower cost.

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희박연소기관용 용량방전식 다회수스파크 점화장치의 개발에 관한 기초 연구 (A basic study on development of multiple- spark capacitor discharge igniter for lean burn engine)

  • 이상준;나성오;이종태
    • 대한기계학회논문집B
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    • 제20권11호
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    • pp.3676-3685
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    • 1996
  • Enhancement of the ignitability was necessary to realize the lean burn engine. The characteristics of multiple-spark capacitor discharge igniter(MSCDI) usefulness of which for lean burn was examined in constant volume combustion chamber and evaluated in spark ignition engine. Noise of MSCDI for engine was restricted by adoption of low voltage control system. It was found that the adaptability for high engine speed was remarkable. Lean limit in engine with MSCDI was extended 10% than conventional coil ignition system. Also maximum brake thermal efficiency was almost enhanced 1%.

고감도 삼상력률계전기에 관한 연구 (Study on the High Sensitive Three Phase Power Factor Meter and Relay)

  • 박정후
    • 수산해양기술연구
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    • 제16권1호
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    • pp.43-47
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    • 1980
  • The author designed and tested the high sensitive three-phase power factor meter and relay circuit, and dealt with the circuit to detect the phase of the current and the voltage. An operational amplifier comparator circuit and two single-phase transformers are used to control and detect the phase angle between the current and the voltage. The results obtained are as follows: 1. Converting the sine wave input current into the constant amplitude rectangular wave form by using a transistor chopper circuit, the power factor can be measured precisely over the load current of 0.08 A. 2. Using the moving coil type current meter, the power factor meter can be read in uniform . scale all over the range. 3. Using the three-phase power factor meter, the power factor relay which works at any power factor can be made.

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직선운동하는 Halbach 배열 가동자와 폐루프 코일 사이의 작용력 해석 (Analysis of force between linear moving Halbach array and a closed loop)

  • 장석명;차상도;이성호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.90-92
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    • 2001
  • The lift and drag forces on various magnet moving with a velocity is developed above a closed loop coil. These forces are affect by resistance and inductance of circuit, velocity of magnet. To obtain strong magnetic flux density, the magnet is replaced by Halbach array. This paper presents analysis of force between linear motion Halbach array and a closed loop having the constant resistance and inductance as a various speed.

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