• Journal of Electrical Engineering and Technology
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• 제13권2호
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• pp.829-837
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• 2018

In this paper, a flux linkage model based on four magnetization curves fitting is proposed for three-phase 12/8 switched reluctance motor (SRM), with the analysis of the basic principle of flux detection method and function analysis method. In the model, the single value function mapping relationship between position angle and flux is established, which can achieve a direct estimation of rotor position. The realization scheme of SRM indirect position detection system is presented. It is proved by simulation and experiment that the proposed scheme is suitable for rotor position detection of SRM, and has high accuracy of position estimation.

• 전기학회논문지
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• 제66권11호
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• pp.1657-1662
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• 2017

Rotor bar faults in induction machines, which are a part of main distribution of power system, can even stop the entire system by causing contact between a stator and a rotor. There are two methods of diagnosing rotor bar faults in induction motors, online and offline tests, and existing diagnosis methods have many limitations which can lead to misdiagnosis. This paper proposes a potable rotor bar faults diagnosis system based on single phase rotation test, one of offline test methods, which detects rotor bar faults through impedance interpretation by exciting AC current in a stator winding. The test was conducted on a motor of 0.4kW in the laboratory and a motor of 1500kW in industry field.

• 제어로봇시스템학회논문지
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• 제3권3호
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• pp.280-288
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• 1997

In this paper, we will show that the torque ripple in closed-loop drives of permanent magnet stepping motors is reduced as properly selected lead angle control method. We propose an instantaneous torque equation, which is the function of lead angle, to estimate the influence on torque ripple. We design a closed-loop lead angle control system based on the proposed instantaneous torque equation and measure the instantaneous torque in various excitation modes. It is shown that torque ripple is greatly reduced, as seen from the experimental results as well as from the computer simulation results. For example, torque ripple reduced from 78.25% to 46.82% in the case of 50 PPS single-phase excitation mode operation.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제49권1호
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• pp.15-19
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• 2000

The main advantages of DSPSRM lie in the simple robust construction, low manufacturing cost and simple driving circuit. Especially, it is possible to make shortly the axial length of DSPSRM. therefore, it is suitable to setup this motor in a narrow space. For practical use, prototype of DSPSRM was already manufactured. In this paper, we explain driving method and design driving circuit of DSPSRM. And then speed, torque and efficiency are measured. As a result of measurement, the torque was constant at normal speed and the speed was linearly increased as the current increase. Therefore, we verify that DSPSRM is suitable for low-speed fan load.

• EDISON SW 활용 경진대회 논문집
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• 제5회(2016년)
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• pp.411-416
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• 2016

Existing moving robots has several kinds of moving method; using wheel, jointed leg structure and so on. Wheel type can be operated by DC motor so it is simple and efficient. However, it is not appropriate to pass irregular terrain and obstacle. Leg structure type has an advantage in those cases. Generally, Leg structure is operated by several servo motors attached to each joint. It makes a robot heavier and more complicate due to increase of the degree of freedom. However, by using Theo Jansen Mechanism, one (or more) leg have only single-degree of freedom and can be operated by only one DC motor. So leg structure using Theo Jansen Mechanism will be good choice if robots have to be mass-produced. This paper describes the following a walking robot designed and produced based on Theo Jansen Mechanism, simulating process of Theo Jansen leg structure using Edison m.Sketch and how to solve several of discovered problem of the robot.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.997-998
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• 2007

This paper deals with analytical solution concerning the image method using the magnetic charge instead of 3D FEA(finite element analysis) in the slotless single air-gap motor. The theory of analytical method and the design procedures are introduced. The reliability and validity of proposed analytical solution are verified through the comparison with the results of commercial 3D FE software. In addition, calculation time between proposed analytical solution and 3D FEA is compared. Finally, characteristics, such as Back-EMF and phase resistance, between calculated and experimental results are compared. From the verification with 3D FEA and experimental results, it is proved that presented analytical method provided very effective and precise results.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 추계학술대회논문집
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• pp.802-808
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• 2000

This paper characterizes the electromechanical parameters due to the fault of rotor bars in a squirrel cage induction motor. Simulation is performed to investigate how broken rotor bars have effect on them by solving the time-stepping finite element equation coupled with magnetic field equation, circuit equation and mechanical equation of motion. It shows that the asymmetry of magnetic flux due to the broken rotor bar introduces the beating phenomenon in time domain and the sideband frequencies in frequency spectra, respectively, to the stator current, torque, speed, magnetic force and vibration of a rotor. However, vibration of a rotor would be the most effective monitoring parameters to detect the faults of rotor bars.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2006년도 추계학술대회 학술발표 논문집 제16권 제2호
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• pp.228-231
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• 2006

모터의 설계를 위해서는 여러가지 방법에 의해서 해석을 먼저 수행하는 것이 필수적이다. 이를 위해서는 시스템에 대한 최적 모델링이 필수적인데 모터의 전자기적인 해석에는 비선형성이 크기 때문에 최적의 모델링이 쉽지 않다. 특히 집중권선 방식을 이용한 유도기는 자속의 집중으로 인해 고조파 발생 등 많은 문제점을 안고 있어서 실제로 유도기 설계시 설계자들이 많은 어려움을 겪고 있으며, 많은 설계자들은 대부분 등가회로를 이용한 방법으로 시뮬레이션하고, 자신의 경험을 바탕으로 시행착오를 거쳐 가면서 설계를 하고 있다. 그러나 그렇게 설계된 제품이 최적의 설계인지도 의문시 되는 경우가 대부분이다. 따라서 본 논문에서는 모터의 최적설계를 위하여 기존 개발한 집중권 방식 유도기를 대상으로 신경회로망을 이용하여 시스템을 모델링하였고, 그 결과를 확인하기 위해 기존 개발한 집중권 유도기의 실측치와 신경회로망을 이용하여 모델링한 방법을 비교, 제시하였다.

• 전기학회논문지
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• 제66권11호
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• pp.1568-1574
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• 2017

This paper studied cogging torque reduction effect for sloping notch applied two notches on stator teeth. We have confirmed accuracy of FEM(Finite Element Method) through comparison previous model using asymmetric notch for experiment and 3D FEM results, and then cogging torque comparison of previous model and sloping notch model. Also the sloping notch model has been modified to step-sloping notch model to consider manufactur. The modification method of sloping notch changed the degree of slope of notch (a)(Notch(a) sloping Deg) and the degree of Slope of notch (b)(Notch(b) Sloping Deg). When Cogging torque is case of minimum, Notch (a) Sloping Deg is $-12[^{\circ}]$ and Notch(b) Sloping Deg $12[^{\circ}]$. In this case, cogging torque was about 23.9[mNm]. Cogging torque of previous model is about 40.8[mNm], so sloping notch model is less than previous model by 41.42[%]. Also, if sloping notch model is changed to step-sloping notch model, cogging torque of step-sloping notch model is about 24.82[mNm], Therefore the difference between the two cogging torque is about 3.85[%], so step-sloping notch model can be applied when considering manufacture.

• 조명전기설비학회논문지
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• 제20권1호
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• pp.100-110
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• 2006

자속 역전식 전동기(Flux Reversal Motor: FRM)는 고정자 치 표면에 영구자석을 갖는 구조이며 회전자가 돌극 형태이므로 관성이 적고 기계적으로 강인한 특성을 지녀서 고속기로의 적용이 가능하다. 그러나 단상 FRM은 구조적 특징으로 인하여 영구자석의 감자가 쉽게 일어나며, 고속 구동시 스위칭 주파수가 커짐에 따라 철손이 크게 상승하게 된다는 한계점을 지닌다. 본 논문에서는 유한요소법을 이용하여 단상 FRM의 설계 파라미터가 전동기의 감자특성에 주는 영향을 고찰해보았고 그 해결 방안을 제시하였으며 철손 특성을 분석하였다.