• 전기의세계
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• 제19권2호
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• pp.6-11
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• 1970

For the variable speed in automatic control, this paper describes, at first, performance equations of an induction motor which has the free rotating stator. This motor with rotating stator has a speed control factor itself by equivalent variable frequency in stator side. Secondly, an additional invertor source on the rotor slip ring serves the purpose of improving the speed control factor. The advantages decribed above permit to control the speed continuosly from zero to maximum allowable speed with low energy of thyristor a feed-back device may be used for speed stabilization under variable load.

• Journal of Power Electronics
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• 제8권3호
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• pp.268-274
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• 2008

This paper presents a proposed position controller for a vector controlled induction motor. The position controller design depends on the rotational motion equations and a classical speed controller (CSC) performance. The CSC is designed to have the ability to track variable reference inputs and to provide a predefined system performance. Standard position controller in industry is presented to analyze its performance and its drawbacks. Then the proposed position controller is designed, based on the well defined rotational motion equations. The proposed position controller and the CSC are applied to control the position and speed of the vector controlled induction motor with different ratings. Simulation results at different operating conditions are presented to evaluate the proposed controllers' performance. The results show that the CSC can drive the motor with a predefined speed performance and can track a variable reference speed with an approximately zero steady state error. The results also show that the proposed position controller has the ability to effect high-precision positioning in a limited time and to track a variable reference position with a zero steady state error.

• 전기학회논문지
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• 제62권9호
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• pp.1234-1239
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• 2013

This paper provides a technical review of speed control using variable gain PI algorithm for BLDC(Brushless DC) motor. Usually the PI control is used in many motor applications, but a general PI control has problems of overshooting and disturbance for response. By the change of PI gain in motor control operation, these problems can be solved. To find the optimized PI gains for BLDC motor control, many control methods have been proposed. In this paper, the control algorithm with a variable PI gain is applied to improve overshooting response in transient region and rapid load disturbance rejection. Fixed gain and variable gain PI controls are compared. The validity of the propose method is verified by experiment.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.652-655
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• 1996

This paper develops an AC motor controller for applications. The AC motor controller is designed based on the variable structure control method and a variable structure disturbance observer is added to reduce the effects of exogenous disturbances. The designed controller is installed on the z-axis of a CNC machining center and milling experiments were performed. The results show improved performance on both position and speed tracking, when compared to the factory-designed servo controller.

• 한국소음진동공학회논문집
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• 제25권6호
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• pp.414-419
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• 2015

Recently, commercial ships and other specialized vessels with electric propulsion system employ variable speed induction motor as its prime mover. The wide application of electrical motors also includes being the main drive system in most industrial machineries. However, during its start-up, shutdown, and brake switch operation, excessive torque variation are generated. As such, flexible coupling are installed in order to reduce the transmitted torque fluctuation to the driven side. In this paper, the pulse torque generated by an variable speed induction motor was analyzed theoretically and through measurement of torsional vibration. Induction motor with inverter on marine propulsion system and industrial compressor were used as experimental subjects. The study confirmed that pulse torque are generated regardless of motor speed and interpreted as a vibration source of the whole system. Results presented herein can be adopted as the basis in future amendment of inspection classifying body regulations.

• 대한전기학회논문지:시스템및제어부문D
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• 제53권8호
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• pp.545-550
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• 2004

This paper is proposed a fuzzy neural network controller based on the vector controlled induction motor drive system. The hybrid combination of fuzzy control and neural network will produce a powerful representation flexibility and numerical processing capability. Also, this paper is proposed estimation and control of speed of induction motor using ANN Controller. The back propagation neural network technique is used to provide a real time adaptive estimation of the motor speed. The error between the desired state variable and the actual one is back-propagated to adjust the rotor speed, so that the actual state variable will coincide with the desired one. The back propagation mechanism is easy to derive and the estimated speed tracks precisely the actual motor speed. This paper is proposed the theoretical analysis as well as the simulation results to verify the effectiveness of the new method.

• 전력전자학회논문지
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• 제2권1호
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• pp.39-45
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• 1997

초고속 전동기 구동 시스템을 위하여 간접 신경회로망 제어기를 제안하였다. 고속의 가변 전동기구동에서의 속도응답은 긴 정착시간과 높은 오버슈트의 영향에 있게 되므로 고성능을 위하여 신경회로망 제어기와 신경회로망 에뮬레이터로 구성된 제어기를 사용하였으며, 신경회로망 에뮬레이터는 고속 전동기의 정수와 특성을 동정하는데 사용하였고, 제어기의 학습은 접속강도가 백프로퍼게이션에 의해 조절되도록 하였다. 그리고 시뮬레이션과 실험을 통하여 제안된 시스템의 특성과 장점을 확인하였다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2012년도 전력전자학술대회 논문집
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• pp.512-513
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• 2012

The electric motor is essential to drive turbo machinery. In order to overcome the speed limitations of general motors, the inverter is used to perform high speed to tens of rpm. The high speed drives are widely used in many applications such as turbo blower, turbo centrifugal compressors, and pump using air bearing technique. Starting of high speed motor can cause step out, stall, oscillation of motor because the phase inductance is much smaller than that of ordinary motor. This paper studied on the starting characteristic of variable speed centrifugal chiller considering high speed motor characteristics. Finally, the superiority of the inverter is verified by experimental results.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제53권2호
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• pp.90-98
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• 2004

Variable-speed drives are being continually innovated. Recently, sensorless induction motor drives have been much studied due to several advantages. Most sensorless algorithms are based on the mathematical modeling of motors, and all the information is obtained from the monitored voltages and currents. Therefore, the accuracy of such variables largely affects the performance of a sensorless induction motor drive. However, the output voltage of the SVPWM-VSI which is widely used in a sensorless induction motor drive has a considerable error, especially in a low speed range. This paper proposes a variation of the dc link voltage as a high-performance strategy for overcoming the above problem. The proposed strategy leads to an improved resolution of the output voltage of the SVPWM-VSI in a sensorless induction motor drive. Simulation and experiment have been performed for the verification of the proposed strategy.

• 전기학회논문지P
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• 제55권3호
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• pp.117-122
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• 2006

The paper is proposed artificial neural network(ANN) sensorless control of induction motor drive with fuzzy learning control-fuzzy neural network(FLC-FNN) controller. The hybrid combination of neural network and fuzzy control will produce a powerful representation flexibility and numerical processing capability. Also this paper is proposed. speed control of induction motor using FLC-FNN and estimation of speed using ANN controller. The back Propagation neural network technique is used to provide a real time adaptive estimation of the motor speed. The error between the desired state variable and the actual one is back-propagated to adjust the rotor speed so that the actual state variable will coincide with the desired one. The proposed control algorithm is applied to induction motor drive system controlled FLC-FNN and ANN controller, Also, this paper is proposed the analysis results to verify the effectiveness of the FLC-FNN and ANN controller.