JaLCDOI 10.18926/15654
FullText URL Mem_Sch_Eng_OU_7_2_89.pdf
Author Nakata Takayoshi| Ishihara Yoshiyuki| Morimoto Hideki|
Abstract This paper deals with the magnetic characteristics (the flux distributions, core losses, etc.) of threephase core-type transformers with double-layer. In the preceding report, only linear solutions have been given. In this paper, also non-linear solutions are discussed. Therefore, the flux waves of each magnetic path are distorted and contain various harmonics. When core losses are calculated, the hysteresis losses of minor loops are taken account. The results of analysis are compared with those of experiments. It is concluded that the principal cause for increasing core losses of this type core is the eddy current loss produced by harmonic fluxes. The flux distributions and the core losses depend on the shapes of the magnetization curve and the core-loss curve, that is, on the quality of the materials.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1972-10-13
Volume volume7
Issue issue2
Start Page 89
End Page 100
ISSN 0475-0071
language English
File Version publisher
NAID 120002307260
JaLCDOI 10.18926/15653
FullText URL Mem_Sch_Eng_OU_7_2_85.pdf
Author Nakata Takayoshi| Ishihara Yoshiyuki|
Abstract A new method for representing distorted wave forms is investigated. The method suggested by us is a modified vector symbolic method. It has been hitherto thought that the vector symbolic method cannot be applied to the distorted waves, because the rotating speeds of each harmonic vector are not identical. Representing the argument of the n-th harmonic vector by l/n times as large as the phase angle of the harmonic component, the relative positions of respective harmonic vectors are invariable wherever the standard vector is put, and the wave shape can be deduced from the vector diagram. We found various correspondences between the wave forms and the vector diagrams. Therefore, the wave shape can be estimated from the vector diagram, and the mutual relationships between two wave forms can also be known. In electric or magnetic circuits, the causes of distorted wave forms are in general obvious. Therefore, there are very often the fixed relationships between the amplitudes and phase angles of the harmonics. Further, in polyphase a.c. circuits, there are often the fixed relationships between corresponding harmonics in the wave forms of the respective phases. When the wave forms of those circuits are discussed, the new method investigated in this paper may offer a useful key.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1972-10-13
Volume volume7
Issue issue2
Start Page 85
End Page 88
ISSN 0475-0071
language English
File Version publisher
NAID 120002307535
JaLCDOI 10.18926/15650
FullText URL Mem_Sch_Eng_OU_7_2_49.pdf
Author Hosokawa Norio| Kodera Yoichi|
Abstract This paper deals with the stress-strain curves of single crystal and polycrystal considering the workhardening and the anisotropy which is due to the difference of workhardening on each slip system. The results obtained are summarized as follows: 1) The equations of workhardening on each slip system are derived according to the dislocation theory. 2) And it is found that the stress-strain curves of Cu single crystal and polycrystal calculated by using the workhardening equation with proper coefficients agree well with the experimental values.
Publication Title Memoirs of the School of Engineering, Okayama University
Published Date 1972-10-13
Volume volume7
Issue issue2
Start Page 49
End Page 60
ISSN 0475-0071
language English
File Version publisher
NAID 120002307885