• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.6
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• pp.889-895
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• 2011

PMLSM is structurally simple and it have a lot of merits such high speed, high thrust force etc., but cogging force by slot-teeth structure of armature and cogging force by outlet edge effect occurs. This is the cause of thrust force ripple and generate the noise and vibration. Therefore, in this paper we proposed installation of an auxiliary pole to mover of the PMLSM in order to decrease cogging force by the outlet edge which came necessarily into being discontinuous arrangement of the armature. Also, outlet edge cogging force designed a form of the auxiliary pole which the minimum became, and we compared a outlet edge cogging force characteristic along a winding method of an armature as we used 2-D of finite element analysis.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.350-355
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• 2003

This paper presents results of vibration analysis of a end-winding of large generator for fossil power plant. A finite element analysis using a commercial S/W is performed to calculate alternating electromagnetic forces, mainly of 120㎐ in 60㎐ machines, acting on the end-winding, and then to calculate forced response of the end-winding under electromagnetic forces. Also, this paper presents analytical and experimental modal analysis results of generator end-winding to validate FE model. We calculated forced response of end-winding on 120㎐, double rotating frequency. These results will be used to evaluate structural reliability of end-winding and applied to update model.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11b
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• pp.826-831
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• 2001

Electromagnetic forces generate vibrations in the end-winding of large generators. A finite element analysis using a commercial S/W is performed to calculate electromagnetic force of end-winding in two pole generator for 500 MW fossil power plant. Also, this paper presents analytical and experimental modal analysis results of generator end- winding. Using validated FE model, 3D electromagnetic model which computes the forces on the end-winding is coupled with a 3D mechanical model which calculates the dynamic displacement and stress under electromagnetic forces. These results will be used to evaluate reliability of end-winding and applied to update model.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.577-582
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• 2020

Electricity produced at power plants is distributed to consumers through several stages of substations. At this time, an ultra-high voltage transformer is needed in the initial transmission stage to transmit a voltage suitable for each consumer. A high voltage, non-uniform electric field is formed at the end of the winding of the ultra-high voltage transformer, which carries a risk of dielectric breakdown. The winding of the ultra-high voltage transformer is an electrode, which is the key to converting the magnitude of the voltage. A non-uniform electric field is formed along the shape of the winding end, resulting in high electrical stress. The static ring installed at the upper and lower ends of the winding is used to disperse the stress at the winding end. Several variables should be considered when designing a static ring. Among them, this study examined how the curvature of the static ring, the thickness of the insulating paper, the number of barriers, and barrier thickness affect the electrical stress of the static ring using the Finite Element Method. Suggestions to be considered when designing the static ring are proposed through the FEM results.

• Proceedings of the KIEE Conference
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• 2000.11b
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• pp.306-308
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• 2000

부분여자된 영구자석형 선형동기전동기(PMLSM)의 단부효과를 고려한 특성을 나타낸다. 선형동기전동기의 고효율 운전을 위하여 전기자 권선을 가동자의 위치별 부분여자하였으며, 이와 더불어 양단부의 제한된 자석길이에 의한 단부효과를 나타낸다.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.979-980
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• 2011

영구자석 선형 동기 전동기(Permanent Magnet Linear Synchronous Motor)는 구조적으로 간단하며 고속화 고추력화 등의 많은 장점을 가지고 있지만 전기자 권선부의 슬롯-치 구조로 인한 코깅력과 단부효과에 의한 코깅력이 발생한다. 이는 추력 맥동의 원인이 되며, 소음과 진동을 발생시킨다. 따라서, 본 연구에서는 전기자를 분산배치할 경우 필연적으로 생기는 단부에 의한 코깅력을 저감하기 위해 기존의 전기자 끝단에 설치한 보조치를 응용하여 계단형 형상을 가진 보조치의 설치를 제안하였다.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.883_884
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• 2009

PMLSM에서는 전기자 권선부의 슬롯-치 구조로 인한 디텐트력과 단부효과에 의한 디텐트력, 영구자석의 고조파 성분 자속에 의한 디텐트력이 발생한다. 따라서, 본 연구에서는 자기저항의 불연속으로 인한 디텐트력을 제거시키기 위하여 전기자 권선과는 독립된 자기회로를 가지는 보조코어의 설치를 제안하였다. 보조코어의 최적 설계는 유한요소 해석과 실험계획법을 이용하였으며 이론치와 실험치를 비교함으로서 본 연구의 타당성을 입증하였다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.527-532
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• 2014

Generator is the main equipment of a power plant that generates electric power. The line frequency is 60Hz, since that is operated at 3600rpm in fossil power plant. Therefore, the specific frequency 120Hz by the electromagnetic excitation force is generated inherently. If the looseness of stator at generator happens, abnormal sound that has 120Hz and the harmonic frequency is emitted from generator frame. In that case, binding of end-winding or re-wedging is needed for the reduction of sound level. In case of severe level of sound, belly band can be additionally installed at core. In this paper, the characteristics of generator sound is described and modal data is analyzed after installation of belly band.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.816-817
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• 2008

본 논문에서는 2세대 고온초전도 선재인 YBCO CC(Coated Conductor)를 사용하여 접합 없이 권선되는 새로운 형태의 고온초전도 팬케이크형 코일에 영구전류를 인가하기 위한 영구전류 스위치의 형태를 제안였다. 제안된 테이프 형태의 광폭 YBCO CC의 양끝부분을 제외한 중간부분을 2분할하여 감아 뒤집은 형태의 팬케이크 코일에는 접합부분이 없으므로 영구전류가 흐를 수 있으나, 전류의 인가를 위한 스위치를 별도로 제작하여 연결하기 곤란하다는 단점이 있다. 본 연구에서는 감아 뒤집은 고온초전도 팬케이크 코일의 한쪽 단부를 영구전류 스위치로 사용할 수 있는 구조를 제안하였고, 추후 연구에 실제로 사용될 12 mm 폭의 YBCO CC를 사용하여 영구전류 스위치를 제작하고 특성시험을 수행하였다.