• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제48권4호
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• pp.182-186
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• 1999

Evaluation of the AC losses in the HTS tapes which are used in electric power machines in one of the important topics in this field. This paper deals with the calculation and measurement of the magnetization loss in HTS tapes. Bean model is adopted for the theoretical calculation of the magnetization loss. Magnetization method is used for the measurement of the loss. Two types of the HTS tape model, multi-filamentary model and mono-filamentary model, are used to evaluate the magnetization loss in this paper. According to the results of the analysis, large discrepancy between the calculated and measured value is observed in multi-filamentary model is more useful than multi-filamentary model for the evaluation of the magnetization loss.

• 전기전자학회논문지
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• 제17권3호
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• pp.229-233
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• 2013

We investigated electrical conduction and resistance switching behavior of the Ag/ZnO/Ti structures for random access memory devices. These films were prepared on glass substrate by dc sputtering technique at room temperature. The resistance switching follows unipolar switching mode with small switching voltages (0.4 V - 0.6 V). Two electrical conduction mechanisms dominating the LRS and HRS are Ohmic and trap-controlled space charge limited current, respectively. These both conductions are consistent with the filamentary model. Based on the filamentary model, the switching mechanism was also interpreted.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권1호
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• pp.29-33
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• 1999

Superconducting tape is being developed for electrical equipment such as superconducting transformers and generators etc. AC loss reduction is primary concerned in the development of such high-efficiency equipment. AC losses in Bi-2223 silver-sheathed tapes, both single and multi-filamentary, were investigated by means of AC magnetization techniques when longitudinal fields are applied. The experiment resultswere compared with the hysteresis loss equation based on Bean model and the eddy current loss equation. The AC loss of the mono-filamentary tape was dominated by the hysteresis. On the contrary, the AC loss of the multi-filamentary tape was substantially dominated by the eddy current loss in the silver matrix.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 C
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• pp.1050-1053
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• 1998

To be applied to electrical equipment HTSC tapes have to endure external stress and so on. The critical current density has been shown depending on the mechanical properties. strain and bending stress. AC loss reduction is primary concern in the development of such high-efficiency equipment. AC losses in Bi-2223 silver-sheathed tapes, both single and multi-filamentary, were investigated by means of AC magnetization techniques. The results were compared with the hysteresis loss equation based on Bean model and the eddy current loss equation. The AC loss of the mono-filamentary tape was the hysteresis. On the contrary, the AC loss of the multi-filamentary tape was substantially dominated by the eddy current loss in the Ag matrix.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 A
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• pp.125-127
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• 1998

Superconducting tape is being developed for electrical equipment such as superconducting transformers and generators. AC loss reduction is primary concern in the development of such high-efficiency equipment. AC losses in Bi-2223 silver-sheathed tapes, both single and multi-filamentary, were investigated by means of AC magnetization techniques. The results were compared with the hysteresis loss equation based on Bean model and the eddy current loss equation. The AC loss, of the mono-filamentary tape was the hysteresis. On the contrary, the AC loss of the multi-filamentary tape was substantially dominated by the eddy current loss in the Ag matrix.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 B
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• pp.702-705
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• 1998

To be applied to electrical equipment HTSC tapes have to endure external stress and so on. The critical current density has been shown depending on the mechanical properties, strain and bending stress. AC loss reduction is primary concern in the development of such high-efficiency equipment. AC losses in Bi-2223 silver-sheathed tapes, both single and multi-filamentary, were investigated by means of AC magnetization techniques. The results were compared with the hysteresis loss equation based on Bean model and the eddy current loss equation. The AC loss of the mono-filamentary tape was the hysteresis. On the contrary, the AC loss of the multi-filamentary tape was substantially dominated by the eddy current loss in the Ag matrix.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부A
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• pp.382-385
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• 1998

To be applied to electrical equipment HTSC tapes have to endure external stress and so on. The critical current density has been shown depending on the mechanical properties, strain and bending stress. AC loss reduction is primary concern in the development of such high-efficiency equipment. AC losses in Bi-2223 silver-sheathed tapes, both single and multi-filamentary, were investigated by means of AC magnetization techniques. The results were compared with the hysteresis loss equation based on Bean model and the eddy current loss equation. The AC loss of the mono-filamentary tape was the hysteresis. On the contrary, the AC loss of the multi-filamentary tape was substantially dominated by the eddy current loss in the Ag matrix.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2003년도 학술대회 논문집
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• pp.11-14
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• 2003

The magnetization and self-field losses of the four technical high-T$_{c}$ superconducting tapes have been investigated experimentally. The results show that the magnetization losses for parallel or perpendicular fields can be well predicted from the slab model or the strip model for a filamentary region. However the magnetization losses for longitudinal fields can be rather predicted by the slab model for a decoupled filament. The self-field losses are well explained by the Norris ellipse model.l.

• 한국초전도ㆍ저온공학회논문지
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• 제17권2호
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• pp.25-30
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• 2015

In order to realize economical applications, it is important to reduce the ac loss of 2G high-temperature superconductor coated conductors. It seems to be reasonable that a multi-filamentary wire can decrease the magnetization loss. In this study, we prepared two samples of YBCO coated conductors with striations. We measured local superconducting properties of both samples by using Low Temperature Scanning Laser and Hall Probe Microscopy (LTSLHPM). The distribution of the local critical temperature of samples was analyzed from experimental results of Low Temperature Scanning Laser Microscopy (LTSLM) near the superconducting transition temperature. According to LTSLM results, spatial distributions of the local critical temperature of both samples are homogeneous. The local current density and the local magnetization in samples were explored from measuring stray fields by using Scanning Hall Probe Microscopy (SHPM). From SHPM results, the remanent field pattern of the one bridge sample in an external magnetic field confirms the Bean's critical state model and the three bridge sample has similar remanent field pattern of the one bridge sample. The local magnetization curve in the three bridge sample was measured from external fields from -500 Oe to 500 Oe. We visualized that the distribution of local hysteresis loss are related in the distribution of the remanent field of the three bridge sample. Although the field dependence of the critical current density must be taken into account, the relation of the local hysteresis loss and the remanent field from Bean's model was useful.

• Journal of Electrical Engineering and Technology
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• 제7권1호
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• pp.86-90
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• 2012

A two-dimensional nonlocal heating theory of planar-type inductively coupled plasma source has been previously reported with a filamentary antenna current model. However, such model yields an infinite value of electric field at the antenna position, resulting in the infinite self-inductance of the antenna. To overcome this problem, a surface current model of antenna should be adopted in the calculation of the electromagnetic fields. In the present study, the reactor impedance is calculated based on the surface current model and the dependence on various discharge parameters is studied. In addition, a simpler method is suggested and compared with the surface current calculation.