Research on Improvement in Accuracy of Measurement by Digital Technique under High Electromagnetic Environments
Grant-in-Aid for Developmental Scientific Research
|Allocation Type||Single-year Grants |
|Research Institution||University of Tokyo |
KAWAMURA Tatsuo Institute of Industrial Science, University of Tokyo, Professor, 生産技術研究所, 教授 (20013097)
河村 達雄 (1986) 東京大学, 生産技術研究所, 教授
OOKUBO Hitoshi Heavy Apparatus Engineering Lab., Toshiba Corporation, Manager, 重電技術研究所, 担当課長
MATSUMOTO Takaie Faculty of Engineering, Shizuoka University, Associate Professor, 工学部, 助教授 (40157368)
ISHII Masaru Institute of Industrial Science, Univ. of Tokyo, Associate Professor, 生産技術研究所, 助教授 (40107397)
ISAKA Katsuo Faculty of Engineering, Tokushima University, Associate Professor, 工学部, 助教授 (50035630)
HARADA Tatsuya Faculty of Science and Engineering, Saga University, Professor, 理工学部, 教授 (10183568)
|Project Period (FY)
1985 – 1986
Completed (Fiscal Year 1986)
|Budget Amount *help
¥11,100,000 (Direct Cost: ¥11,100,000)
Fiscal Year 1986: ¥4,600,000 (Direct Cost: ¥4,600,000)
Fiscal Year 1985: ¥6,500,000 (Direct Cost: ¥6,500,000)
|Keywords||High Voltage / Impulse Voltage / Electromagnetic Compatibility / ディジタル計測|
For the purpose of improving accuracy in measurements using digital technique under high electric and magnetic fields, evaluation of electric and magnetic fields themselves is essential. Through the measurement of electromagnetic fields in the vicinity of a small impulse generator by using electric and magnetic field sensors with the frequency bandwidth of 100MHz, assessment of these fields and development of a measuring system have been carried out.
Electric and magnetic fields due to the natural lightning on the Japan Sea side of Honshu island have been recorded using an automatic digital data acquisition system. The authors obtained a lot of data on electric and magnetic fields in winter, which had scarcely been available in the world due to the small number of occurrence.
Comparative measurements by analog and digital technique on power-frequency electric field exposure of a human body, current through a human body due to electrostatic induction of power frequency, surge current thro
ugh polluted insulators, high frequency current generated in a gas insulated switchgear have been carried out. These are the phenomena in high electromagnetic fields under a transmission line or in the vicinity of a gas insulated switchgear. Signal transmission by optical methods has been shown to be very effective for the purpose of precise measurement using digital techniques. Under high electromagnetic fields, only this method can avoid the deterioration of measuring accuracy.
Theoretical and experimental investigations on the measuring accuracy of A/D converters, which have the greatest influence on the accuracy in measurements using digital technique, have been carried out. The result shows large variation among each instrument and few instruments assure the accuracy predicted theoretically.
Based on the above results, a standard digital measuring system under high electromagnetic fields has been manufactured for trial which served for an experiment performed in a large high voltage laboratory. Based on the results of the experiment, standardization of a digital measuring system has been investigated.
Based on the results of this research, further investigations aiming identification of test conditions and standardization of the test method will be carried out bearing in mind robustness of the measuring and control systems to these field conditions. Less
Report (2 results)
Research Products (8 results)