• KIEE International Transactions on Power Engineering
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• 제2A권3호
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• pp.114-120
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• 2002

This paper describes the symptoms with the fault causes of pole transformers analyzed by Korea Electric Power Corporation(KEPCO) branch offices' request in 2001, and ultimately aims to devise proper countermeasures against the faults. The fault causes are generally divided into problems in manufacturing, mounting and operating. The pole transformers encounter the fault with unique aging mechanisms. To verify the mechanisms with the faults and to devise proper countermeasures, a flowchart for analyzing the fault causes is proposed, by which the fault causes of the pole transformers can be analyzed more exactly.

• 조명전기설비학회논문지
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• 제20권3호
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• pp.78-83
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• 2006

본 연구에서는 통신선 가설 보조 기구인 조가선에 이상 장력이 작용하였을 때 전주의 영향을 유한 요소 해석을 통하여 전주 보호 기구를 설계 해석하여 보호시스템을 개발하였다. 보호시스템은 일반하중 또는 풍압과 일반적인 불평형 하중에서는 조가선이 탈락되지 않고 일정강도 이상이 가해지면 조가선이 자동 탈락되어 전주의 절손 방지 역할을 한다. 이러한 보호시스템의 구조는 유한 요소 해석을 통하여 해석되어졌고, 실제 제품에 대한 인장강도를 측정함으로써 성능을 입증하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 B
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• pp.690-692
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• 2003

The single phase switched reluctance motor has been studied and developed actively in the various applications with several kinds and forms because of the developments of the design technique by using the computer and of the driving technique power electronic technology, which has the merits of a simple and robust structure, and first of all reducing the number of the switching devices in comparison with poly phase switched reluctance motor. And also, the studies are making progess to substitute the switched reluctance motor for single phase induction motor. In the previous studies, the single phase switched reluctance motor for the drive of blower is designed with the design theory of the conventional rotating electric machine and poly phase switched reluctance motor. In this paper, we intend to select the optimal pole arc and pole pitch ratio by the FEM analysis, because the pole arc and pole pitch are very important factor to determine the characteristics of switched reluctance motor.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1017-1018
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• 2007

Interior permanent magnet synchronous motor (IPMSM) for traction motor in the hybrid electric vehicle (HEV) has different parameters and characteristics according to pole and slot combinations. The fitting combination of pole and slot in the IPMSM improves characteristics of traction system ultimately. This paper deals with analyzing the characteristics of IPMSM for mild type HEV according to pole and slot combinations. Based on the result of characteristics, suitable pole and slot combination is presented to maximize efficiency of traction motor in the HEV system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 A
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• pp.276-278
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• 1999

In this paper, we analyze customers' working electric energy (kWh) which is served pole-transformer in order to reduce peak load current error which is generated in application load correlation equation. The characteristic of electric load which customers are using is classified by customer's working electric energy (kWh) and ratio of cooling equipment possession. For the input data of fuzzy model, we used to kWh on April which represents basic load and kWh which is increased from April to August. The April kWh is used to classify into large, medium, small customer. Also, the increased kWh is used to know information of cooling equipment possession. For the output value of fuzzy model, we can determined peak load current limit in application load correlation equation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 정기총회 및 창립40주년기념 학술대회 학회본부
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• pp.76-78
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• 1987

This paper describes the theory and application of a multi-input/multi-output self-tuning regulator where the control objective is the assignment of the closed-loop pole set to prespecified locations. The algorithm described In this paper has a 'self-tuning' property. This self-tuners are more robust than the tuners that are based on optimal control synthesis method. This paper demonstrate usefulness of the algorithms by means of some simulation studies.

• Journal of Magnetics
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• 제18권3호
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• pp.268-275
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• 2013

This paper shows the characteristics of performance for interior permanent magnet machine (IPM) considering driving conditions such as maximum torque per ampere (MTPA) and flux-weakening control especially in terms of harmonic loss. In particular, based on finite element analysis (FEA), permanent magnet (PM) eddycurrent loss and the harmonic iron loss have been computed where the models have been intentionally designed to identify the effects of pole-slot combinations on the loss while maintaining the required power for electric vehicle. From the analysis results, it was shown that the rotor iron loss and PM eddy-current loss of machine employing fractional slot winding are extremely large at load condition. Furthermore, it was revealed that the harmonic iron loss at high-speed operation is mainly distributed over stator teeth and rotor surface, which may aggravate cooling system of the rotor structure in the vehicle.

• 한국산학기술학회논문지
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• 제22권6호
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• pp.566-572
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• 2021

본 논문에서는 도시환경과 모래가 많은 토양 아래에 구 형태의 빈 공간이 있을 경우를 가정하고, 해당 목표물의 고유 pole과 고유 공진주파수를 활용하여 목표물을 식별 및 위치를 추정하는 방안을 제시하였으며 가능성을 분석하였다. EM(Electromagnetic) 시뮬레이터를 활용하여 다양한 형태와 크기를 가진 완전도체(PEC: Perfect Electric Conductor)들을 모델링하였고, 이를 통해 획득한 EM 산란응답에 Cauchy 방법을 적용하여 물체의 고유 특성에 해당하는 고유 pole을 축적하여 pole 라이브러리를 생성하였다. 생성된 pole 라이브러리는 목표물에서 추출한 고유 pole과의 비교를 통해 목표물을 식별할 수 있는 가능성을 제공해 준다. 도시환경과 모래가 많은 토양 아래에 구 형태의 빈 공간이 있음을 가정하고 EM 시뮬레이션 모델링을 통해 얻은 전자파 산란 데이터로부터 관심 목표물의 응답을 추출하였으며, 시간영역에서 임펄스 응답의 시간 지연을 이용하여 목표물의 위치를 추정할 수 있었다. 또한 MP(Matrix Pencil) 방법을 적용하여 목표물의 고유 pole을 추출하였다. 최종적으로 계산된 고유 pole과 고유 공진주파수를 pole 라이브러리와 비교하여 탐지된 목표물을 구 형태의 빈 공간(직경 0.2m)으로 추정할 수 있었으며, 계산된 목표물의 위치(깊이)는 약 84 ~ 93%의 정확도를 보였다.

• 전기학회논문지
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• 제61권2호
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• pp.194-198
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• 2012

This paper describes flying inspection apparatus for 22.9kV distribution line. This apparatus is composed of multi-copter(more than 4 propellers), camcorder and remote controller. The existing inspections, such as hot-line inspection job and optical inspection method and distribution Line Checking Robot, have many restrictions. A electric working vehicle and hot-line job license are essential in hot-line inspection job. Besides its high cost, it can't be applied to the electric pole over 18m and road-blocked area. Optical method can't inspect upper side of electric facilities mounted on the electric pole. Robot method can't be applied to the corroded overhead earth wire and nothing of overhead earth wire. To solve the problems, in Korea Electric Power Co., we have applied flying inspection apparatus to the 22.9kV distribution line. The results of trial application show that this paper is practical and effective for the inspection technical method in 22.9kV distribution line

• 전기학회논문지
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• 제57권9호
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• pp.1507-1515
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• 2008

It is essential for electric power companies to have a quick restoration system of the faulted pole transformers which occupy most of transformers to supply stable electricity. However, it takes too much time to restore it when a transformer is out of order suddenly because we now count on operator in investigating causes of failure and making decision of recovery methods. This paper presents the concept of 'Fault pattern analysis and Restoration prediction model using Data mining techniques’, which is based on accumulated fault record of pole transformers in the past. For this, it also suggests external and internal causes of fault which influence the fault pattern of pole transformers. It is expected that we can reduce not only defects in manufacturing procedure by upgrading quality but also the time of predicting fault patterns and recovering when faults occur by using the result.