• 전기학회논문지
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• 제63권3호
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• pp.349-357
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• 2014

The performance of a Synchronous Reluctance Motor (SynRM) in terms of torque and power factor depends on the two-axis inductances $L_d$ and $L_q$ of the machine. The Axially Laminated Anisotropic (ALA) rotor should be proposed in an effort to increase the $L_d/L_q$ ratio and the $L_d-L_q$ difference to secure high torque density and high power factor. So, ALA rotor is suitable for high speed instruments. This paper deals with optimum design of Axially Laminated Anisotropic Synchronous Reluctance Motor (ALA-SynRM) and comparison of characteristics with induction motor. Coupled Finite Element Methodology (FEM) & Response Surface Methodology (RSM) have been used to evaluate optimum design solutions. Comparisons are given with characteristics of a same rated wattage induction motor and those of ALA-SynRM respectively.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 Proceedings of the Korea Automatic Control Conference, 11th (KACC); Pohang, Korea; 24-26 Oct. 1996
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• pp.393-396
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• 1996

This paper studies electrostatically suspended induction motors (ESIM). The ESIM possesses the rotating ability of an ordinary electrostatic induction motor, in addition to providing contactless support by electrostatic suspension. To accomplish these two functions, a feedback control strategy and the operating principle of an ordinary electrostatic induction motor are used. The stator possesses electrodes which exert the electrostatic forces to the rotor and are divided into a part responsible for suspension and one for rotation. Two rotor types are utilized: a polished glass disk without any surface treatment, and a polished glass disk covered with a thin layer of conductive material (ITO layer) on only one side. In this paper, the principle of the ESIM is described, followed by stator electrode design, experimental apparatus, control strategy for stable suspension. Experimental results show that the glass disk has been rotated with a speed of approximately 70 rpm while being suspended stably at a gap length of 0.3 mm.

• 한국자기학회지
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• 제20권6호
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• pp.239-243
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• 2010

본 논문은 반응표면법(Respone Surface Methodology)과 유한요소법(Finite Element Method)을 이용하여 250 kW급 견인 유도 전동기의 효율 향상을 위한 최적설계기준에 대해서 다루었다. 본 논문의 주 관점은 첫째, 회전자 형상 및 치수변화에 따른 토크 비교를 통해 설계 해를 찾는 것이다. 둘째, 중심합성법(Central Composite Design)과 결합된 해석방법이 도입되었고, 추정된 회귀모델의 적합성을 결정하기 위해 분산분석(Analysis Of Variance)이 수행되었다. 이렇게 제안된 실험 절차는 기존의 초기 모델로 부터 시작하여 회전자 형상 및 치수를 최적설계 하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.782-783
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• 2008

This paper deals with optimum design criteria for premium efficiency of 250kW traction induction motor using response surface methodology (RSM) & finite element method (FEM). The RSM has been achieved to use the experimental design method in combination with Finite Element Method and well adapted to make analytical model for a complex problem considering a lot of interaction of design variables. The proposed procedure allows to define the rotor copper bar shape, stator slot and stator, rotor dimensions starting from an existing motor or a preliminary design.

• 대한전기학회논문지:시스템및제어부문D
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• 제54권10호
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• pp.587-594
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• 2005

An adaptive observer for rotor resistance is designed to estimate rotor flux for the a-b model of an induction motor assuming that rotor speed and stator currents are measurable. A singularly perturbed model of the motor is used to design an Adaptive sliding mode observer which drives the estimated stator currents to their true values in the fast time scale. The adaptive observer on the sliding surface is based on the equivalent switching vector and both the estimated fluxes and the estimated rotor resistance converge to their true values. A speed controller considering the effects of parameter variations and external disturbance is proposed in this paper. First, induction motor dynamic model at nominal case is estimated. based on the estimated model, speed controller is designed to match the prescribed speed tracking specifications. Then a dead-time compensator and a robust controller are designed to reduce the effects of parameter variations and external disturbances. the desired speed tracking control performance can be preserved under wide operating range, and good speed load regulating performance. Some simulated results are provided to demonstrate the effectiveness of the Proposed controller.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 A
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• pp.241-243
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• 1996

This papar presents an analysing method of radial force densities acting on each stator tooth of an induction motor with skewed slots. Two-dimensional finite element method is used for electromagnetic Held analysis of an induction motor, and skew effects are considered by coupling several disks cut by planes perpendicular to the shaft. Radial force densities as a source of vibration are calculated along the surface elements of each stator tooth and its time harmonics are examined by discrete Fourier decomposition.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1997년도 전력전자학술대회 논문집
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• pp.171-176
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• 1997

This paper presents a design method of the continuous inertial binary observer which includes the rotor flux and speed estimations. The sliding observer based on the variable structure theory ensures the robustness of disturbance and is applied for the method to keep an insensitivity for the variations of parameter. Sliding observer, however, has a high-frequency chattering deteriorating the state estimation performance. To reduce the chattering on the sliding surface in sliding observer and improve the estimation performance, binary observer scheme which has main advantages such as the absence of high-frequency chattering and the finite gains is applied in this paper. Computer simulation results show the effectiveness of binary observer proposed here for the induction motor drives.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제49권12호
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• pp.797-806
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• 2000

In this paper, the torque characteristics and the bar loss distribution are analyzed when a general cage induction motor with skewed slots is fed by a 6-step inverter. For the electromagnetic analysis, time-stepping finite element method is used. And the multi-slice technique and sliding surface technique are respectively utilized to consider the skew effect and the rotation of the rotor. As a result, the effects of skewed rotor bar and the inverter output voltage on the characteristics of the torque and bar loss in the rotor are investigated. The simulation results are verified by measurement of flux density distribution axially in the stator teeth.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 B
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• pp.726-728
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• 2003

A linear induction motor conveyance system with longitudinal and transverse rails is manufactured. which is controlled by programmable logic controller(PLC). The linear induction motor has a cage-type secondary and the total number of the installed primaries is 10. Four secondaries are installed on the below surface of the moving carrier. In this paper, the developed conveyance system is introduced and its PLC control characteristics for the longitudial and transverse moving directions are presented.

• 대한기계학회논문집A
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• 제28권11호
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• pp.1733-1740
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• 2004

In the transverse flux linear induction motor(TFLIM) with the general secondary composed of conductor and back-yoke, there exists a magnetized force into the normal direction or the air-gap direction of the thrust motion as well as the thrust force. Therefore, the various methodologies have been tried to use the normal force by the two independent control variables of the multi-phase input. But, as the force depends inevitably and strongly on the thrust force, it is essential to decouple both forces for two control index. In this paper, we suggest a novel approach capable of compensating the couple between both forces and the control index by using the DC-biased multi-phase input, and then realizing the independent control of TFLIM.