• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 A
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• pp.47-49
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• 1996

The equivalent circuit of LIM is generally composed as the same that of rotary induction motor. However it is very difficult to move the LIM at synchronous velocity for open-secondary circuit test. The resistance representing the core losses in the primary core can not be ignored because the air-gap of LIM is larger than that of rotary induction motor. In this paper, the T-type equivalent circuit of a LIM with the core loss resistance is chosen using static zero slip test and theoritical analysis.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 하계종합학술대회 논문집
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• pp.567-570
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• 1989

A constant V/F control system of voltage contrlled PWM inverter has a unstable operation of the low- speed and the light-load. In this paper, the authors propose stability control with idealized operation of induction motor by the neglect of primary leakage inductance and resistance. Also ldealized operation system is adopted voltage error, feed back impedance circuit, and increasing resistance from dead time of switching is compensated by the soft ware with u-processors. The proposed simulation of the idealized control method is proved at the low-speed operation for three phase induction motor.

• 전기학회논문지
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• 제60권10호
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• pp.1903-1914
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• 2011

In this paper, we propose vehicle running characteristic simulator. The developed simulator is configured by two induction motors which are directly coupled with each other. One motor is to simulate the vehicle drive and another motor is to simulate the vehicle dynamic load including running resistance, gradient resistance and adhesive characteristics between rail and wheel. The running characteristics of vehicle are modeled by numerical formulas. These are programed by software of embedded controller. Thus, it is possible to change several running characteristics during the running test freely and instantly. To evaluate the feasibility of the simulator, the experiments on slip and adhesion coefficient are performed. Additionally the adhesion control and speed control of vehicle are tested with simulator. Experimental results show that the simulator can produce the driving characteristics similar to the vehicle system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 B
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• pp.723-725
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• 2000

This paper presents a parameter identification method to estimate the stator resistance. stator inductance, rotor resistance and rotor inductance of the induction motor. A step voltage is applied across the stator terminals while the machine is in the standstill condition, and the resulting stator voltage and current response are measured. Observer/Kalman Filter Identification(OKID) algorithm is used to estimate induction motor parameters. Simulation results are presented to verify the identified model.

• 한국동물학회지
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• 제25권1호
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• pp.29-29
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• 1982

Carcinogenesis is extremely complex. Therefore, it is paradoxical but nonetheless important in cancer research if, in an animal whose parental strains are normally sensitive to cancer induction, we could find mutant strains which are resistant to various carcinogens as a result of mutations in one or two genes. No such mutants have been reported so far as I am aware but we do know that at early stages in their development, fish, mice, and humans are highly resistant to cancer induction by chemicals and radiation. I will give a brief overview of the stage-dependent resistance of fish, mice and humans to cancer induction and discuss the stem-cell mutation theory to explain the cancer-resistant stages. Finally, the latent period of induced neoplasms will be discussed in relation to the stem-cell mutation theory.

• Journal of Electrical Engineering and Technology
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• 제8권1호
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• pp.110-117
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• 2013

Maximum Torque Per Amp (MTPA) control for induction motor drives seeks to achieve a desired torque with the minimum possible stator current. This is favorable in terms of inverter operation and nearly optimal in terms of motor efficiency. However, rotor resistance variation can cause significant performance degradation. This work demonstrates that existing MTPA controls perform sub-optimally as temperature varies. An adaptive MTPA control strategy is proposed that always achieves optimal performance without exhibiting hunting phenomenon regardless of rotor temperature. The proposed control is experimentally shown to accurately achieve the desired torque.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제52권6호
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• pp.286-290
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• 2003

The high temperature superconducting bulk can be used as the bearing of induction motors. This paper presents the fabrication and test results of an induction motor with superconducting bearings using HTS bulks. The bearing had eight hexahedron type YBCO bulks. Height, width and thickness of the HTS bulk were 30mm, 30mm and 10mm, respectively. Single phase induction motor was used to drive the shaft made of aluminum and the rotor of a conventional induction motor. To estimate the performance of the HTS bulk magnetic bearing, no load test, load test and Impact test were carried out. Load tests were performed by using air resistance caused by the shaft-mounted thin cylinder with buckets. Impact tests by axial direction and vertical direction impact showed that the vibration of the shaft gradually decayed. The induction motor with HTS bulk magnetic bearing rotated silently and smoothly throughout the tests. According to the test results, conventional bearings can be replaced with superconducting magnetic bearings made of HTS bulks.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2002년도 추계종합학술대회
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• pp.808-811
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• 2002

유도전동기 센서리스 벡터제어의 안정성에 대하여 많은 연구가 되어지고 있다. 그 결과 유도전동기의 고정자 저항, 회전자 저항, 시스템 파라미터의 변화에 대하여 센서리스 방법이 속도 센서가 있는 경우와 비교하여 불안정하게 되기 쉽다는 것이 분명하다. 본 논문에서 속도 지령 $\omega$$_{r}$일 스텝 변화에 대하여 관성 모멘트 J 를 변화하는 경우, 유도전동기 회전자 저항 R$_{r}$,을 변화하는 경우에 대해 살펴보고, 전동기의 파라미터, 시스템 파라미터의 변화에 영향을 받지 않는 제어 방법으로 전동기 전압, 전류, 전동기 정수에 의한 속도 Observer를 구성하여 속도 추정을 행하는 방법에 대하여 제안하고 타당성을 입증하고자 한다.

• 전력전자학회논문지
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• 제4권1호
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• pp.43-49
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• 1999

본 연구에서는 비선형 시스템을 선형 시스템으로 변환시키는 미분기하이론에 기초를 둔 비선형 궤환 선형화 기법을 유도전동기와 같은 비선형 시스템의 제어에 응용함으로써 완전한 비간섭 시스템을 얻을수 있음을 보였다. 또한, 엘리베이터와 같은 부하의 정속도 운전시 효율제어를 위해 회전자 자속을 변화시킬 때 이의 영향을 받아 값이 바뀌는 인덕턴스와 온도에 따라 가장 변화가 심한 회전자저항을 위한 추정알고리즘을 제안하고 이의 성능을 평가해 보기 위하여 시뮬레이션과 실험을 수행하였다.

• 조명전기설비학회논문지
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• 제12권3호
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• pp.99-103
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• 1998

본 논문에서는 속도와 회전자 자속을 비간섭시킴으로써 전기설비등에 많이 적용되는 유도전동기를 고성능으로 제어할 수 있는 비선형 제어기를 제안한다. 이 비선형 제어기는 전동기 매개변수들에 대한 정보릎 필요 로한다 그중에 회전자 저항은 전동기 온도에 따라 크게 변한다. 또한, 이 비선형 제어기에 적용할 수 있는 새로운 (재귀)궤환형 회전자 저항 추정 알고리즘을 제안하고 본 알고리즘의 실용성을 입증하기 위하여 실험결과를 제시한다.