• Journal of Power Electronics
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• 제9권3호
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• pp.354-364
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• 2009

Rotor resistance variation due to changing rotor temperature is a significant issue in the design of induction motor controls. In this work, a new on-line rotor resistance estimator is proposed based on an alternate qd induction machine model which provides better mathematical representation of an induction machine than the classical qd model (which uses constant parameters). This is because the former simultaneously includes leakage saturation, magnetizing path saturation, and distributed circuit effects in the rotor conductors. The comparisons via computer simulation studies show the ability of the proposed estimator to accurately track rotor resistance variation. For the experimental studies, due to the difficulty in measuring the actual rotor resistance, comparison of the controller performance using the proposed estimator, the classical qd model based estimator, and no estimator is made.

• Transactions on Control, Automation and Systems Engineering
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• 제4권4호
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• pp.253-263
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• 2002

This paper presents an adaptive feedback linearization control scheme for induction motors using stator fluxes. By using stator flukes as states, overparameterization is prevented and control inputs can be determined straightforwardly unlike in existing schemes. This approach leads to the decrease of the relative degree for the flux modulus and thus yields a simpler control algorithm than the prior results. In this paper. adaptation schemes are suggested to compensate for the variations of stator resistance. rotor resistance and load torque. In particular, the adaptation to the variation of stator resistance with a feedback linearization control is a new trial. In addition, to improve the convergence of rotor resistance estimation, the differences between stator currents and its estimates are used for the parameter adaptation. The simulations show that torque and flux are controlled independently and that the estimates of stator resistance, rotor resistance, and load torque converge to their true values. Actual experiments on a 3.7㎾ induction motor verify the effectiveness of the proposed method.

• 전기학회논문지
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• 제67권10호
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• pp.1308-1316
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• 2018

Accurate tuning of parameter is very important in vector-controlled induction motor. Among the parameters of induction motor, detuning of rotor resistance used in controller design deteriorates drive performance. This paper presents a novel rotor resistance estimation strategy using slip angular velocity in vector-controlled induction motor drives. The slip angular velocity can be calculated by two methods. Firstly, it can be induced from the rotor voltage equation. Secondly, it can be induced from the difference between synchronous angular velocity and rotor angular velocity. The first method includes the rotor resistance, while the second method dose not include this parameter. From this fact, the rotor resistance can be identified by comparing the slip angular velocities in the two methods. In the tuned states of the rotor resistance, performances of flux estimator and speed drive are discussed. The simulation and experimental results are given to verify the validity of the proposed method in various situations.

• 조명전기설비학회논문지
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• 제30권3호
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• pp.73-78
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• 2016

3phase induction motor consumes 40% of national electric power. so It is one of the most important electric device for the national power policy. The efficiency measurement is carried out by IEC standards. After the temperature rise test, It's difficult to measure the winding resistance immediately. because of inertia and power cut-off time. Therefore, IEC standards suggest the measurement time. But during the measurement time, the winding temperature cools down. It causes the value of winding resistance is variable. Several conditions which possibly occurred by the measurement time of IEC 60034-1 are suggested. and The efficiency evaluation of 3phase induction motors is carried out by IEC 60034-2-1 with the several conditions. As the results, we find out the winding resistance rapidly goes down within 15 sec. so It proves that the winding resistance should be measured within 15 sec. for the efficiency evaluating of 3phase induction motor.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.50-52
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• 2006

This paper Proposes a new method of on-line estimation for rotor resistance of the induction motor in the indirect vector controlled drive, using artificial neural network (ANN). The back propagation algorithm is used for training of the neural networks. The error between the desired state variable of an induction motor and actual state variable of a neural network model is back propagated to adjust the weight of a neural network model, so that the actual state variable tracks the desired value. The performance of rotor resistance estimator and torque and flux responses of drive, together with these estimators, are investigated variations rotor resistance from their nominal values. The rotor resistance are estimated analytically, using the proposed ANN in a vector controlled induction motor drive.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
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• pp.462-465
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• 2001

The wound induction motor can provide high starting torque and reduced starting current simultaneously by inserting large scale resistor. And this technique is one of the well known methods among the induction motor starting methods and generally used for heavy load starting such as Crain and Cement factories. The conventional PI controller has been widely used in industrial application due to the simple control algorithm and in general, PI controller is used for control of current, torque, position, and speed for the wound induction motor drive system. However, the system may result in poor performance since sensors have to be used, which in turn is limited by the environmental condition. Recently, to overcome these problems, many sensorless vector control methods for the wound induction motor have been studied. This paper presents MRAS method with on-line stator resistance tuning for sensorless vector control of the wound induction motor drive. In conventional MRAS method, in low frequency, stator resistance variation can result in poor performance. Therefore, to overcome several shortages of the conventional MRAS caused by parameter variation and enhance robustness of the sensor less vector control, this paper investigates a MRAS method with on-line stator resistance tuning for sensorless vector control of the wound induction motor. The validity and effectiveness of the proposed method is verified through digital simulation.

• 조명전기설비학회논문지
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• 제20권10호
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• pp.27-34
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• 2006

본 논문은 드라이브의 간적벡터제어에서 ANN을 이용하여 유도전동기의 회전자 저항을 온라인 추정하기 위한 새로운 기법을 제시한다. 약전파 알고리즘은 신경회로망의 학습을 위해 사용된다. 신경회로망의 실제 상태값과 유도전동기의 요구값 사이의 오차는 신경회로망 모델의 하중값 조절을 위하여 역전파 하여 실제값이 요구값을 추정하도록 한다. 드라이브의 회전자 저항, 토크, 자속응답 성능등 이러한 추정기의 성능은 고유값으로부터 회전자 저항을 연구하게 된다. 회전자 저항은 유도전동기 드라이브의 벡터제어에서 제시된 ANN을 사용하여 추정한다.

• 전력전자학회논문지
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• 제25권1호
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• pp.13-20
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• 2020

Accurate parameters based on equivalent circuit are required for high-performance field-oriented control in a three-phase induction motor. In a normal case, stator resistance can be accurately measured using a measuring equipment. Except for stator resistance, all machine parameters on the equivalent circuit should be estimated with particular algorithms. In the viewpoint of traditional regions, the parameters of an induction motor can be identified through the no-load and standstill test. This study proposes an identification method that uses the d-axis model of the induction motor in a stationary frame with the predefined information on stator resistance. Mutual inductance is estimated on the rotational dq coordination similar to that in the traditional no-load experiment test. The leakage inductance and rotor resistance can be estimated simply by applying different voltages and frequencies in the d-axis model of the induction motor. The proposed method is verified through simulation and experimental results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.872-873
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• 2007

This paper proposes a calculating method of resistance and inductance of end ring of squirrel cage induction motor for 2D finite element analysis. The squirrel cage of induction motor consists of bars and end rings. The resistance and inductance of end ring have an effect on the result of the finite element calaculation. If the end ring were excluded from the analysis, the good result could not be obtained. Therefore, we first simulate an axisymmetric magnetodynamic analysis for the end ring, and then calculate the interbar resistance and the end ring inductance. The calculated values are put into the external circuit of 2D finite element model of the induction motor. The proposed method is verified by comparing the numerical results with the experimental ones.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 A
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• pp.303-306
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• 1994

This paper presents a new rotor resistance identification algorithm for induction motors. The algorithm is derived form the fact that the slip frequency given in the d-q rotating frame is equal to that measured in the x-y fixed frame. Rotor resistance varies greatly with the machine temperature. In certain cases, the rotor resistance can increase 100 % over its ambient or nominal value. This deteriorates the dynamic performance of vector control systems for induction motors. However, the control scheme proposed in this paper is robust with respect to variations in rotor resistance because an efficient identification algorithm for rotor resistance is employed. To illuminate the performance of the proposed controller further, the simulation results are presented.