Grant-in-Aid for Developmental Scientific Research (B)
|Allocation Type||Single-year Grants |
|Research Institution||Okayama University |
NAKATA Takayoshi Okayama University, Department of Electrical and Electronic Engineering, Professor, 工学部, 教授 (50032925)
YAGO Katsuji Aichi Electric Co., Ltd., R&D Section, Chief Researcher, 主任研究員
NOZAWA Tadao Kyushu Kyoritu University, Department of Electrical Engineering, Professor, 工学部, 教授 (10268790)
FUJIWARA Koji Okayama University, Department of Electrical and Electronic Engineering, Associa, 工学部, 助教授 (20190093)
TAKAHASHI Norio Okayama University, Department of Electrical and Electronic Engineering, Profess, 工学部, 教授 (40108121)
|Project Period (FY)
1994 – 1995
Completed (Fiscal Year 1995)
|Budget Amount *help
¥3,100,000 (Direct Cost: ¥3,100,000)
Fiscal Year 1995: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 1994: ¥2,800,000 (Direct Cost: ¥2,800,000)
|Keywords||JIS Standard / IEC Standard / Amorphous Metal / Single Sheet Tester / Geomagnetism / Residual Magnetism / Distortion of Waveform / Intercomparison / Hコイル / 直流偏磁 / ディジタルフィードバック|
In order to propose a draft of "Standard measuring method of magnetic characteristics of amorphous metal for power apparatus" for the IEC,effects of geomagnetism and residual magnetism, etc.on measured magnetic characteristics were investigated. The results obtained can be summarized as follows :
1.Effect of Geomagnetism on Measured Magnetic Characteristics
The results measured inside and outside a magnetic shielding room were compared with each other. It was shown that if the angle between the longitudinal direction of the specimen and the direction of geomagnetism is perpendicular, the performance of the double yoke type of single sheet tester outside the magnetic shielding room is acceptable.
2.Effect of Residual Magnetism in the Yoke of Measured Magnetic Characteristics
It was shown that the effect residual magnetism in the horizontal yoke type of the single sheet tester is larger than that in the vertical one.
3.Effect of Impedance of Winding on Distortion of Flux Waveform
The effects o
f the impedances of the primary winding and the mutual inductor for air-flux compensation of the single sheet tester on the distortion of the flux waveform were investigated. It was shown that the layrs which compose the winding should be connected in series.
4.Improvement of Waveform Controlling Method
In order to reduce the number of iterations of digital feedbacks, a new controlling method for the waveform which estimates the waveform of the applied voltage using the equivalent circuit of the single sheet tester was developed. The time for measuring magnetic characteristics has been considerably reduced by using this method.
5.Intercomparison of Measurements
A Japanese intercomparison of measurements of the magnetic characteristics for amorphous magnetic material was carried out. The results of the institutes have been considerably different and the counter plan is being investigated now.
Now, it is being tried to improve the existent JIS standard by the above investigation. The intercomparison between various countries is prepared in order to propose a new IEC standard. Less