線路分岐部の過渡電磁界解析 Analysis of Electromagnetic Field Transient on Branch Feeders by Numerical Electromagnetic Field Computation
This paper presents the fundamental surge phenomenon when a step voltage is applied to a horizontal line above the ground which has branch feeders. We study line current and voltage at joint with the moment method that calculates electromagnetic field in frequency domain. It is widely noted that the current reflection factor changes to a third at the junction of same three lines in conventional transmission line theory based on TEM wave, and the stepwise current reflected appears overlapping to the incident current. On the other hand, the reflected current from the joint shows the inductive characteristic or the capacitive one depending on the angle between lines, which varies gradually and not stepwise in our numerical analysis considering TM wave. The time characteristic of the voltage at joint depends on the angles also, and the peak voltage is slightly large compared with the voltage by the transmission line theory. These phenomena are caused by the electromagnetic coupling between the main line and branch lines. In addition to the computer simulations, we measured the currents in the miniaturized model lines and the results make the validity of our analysis clear about changes of the reflected current depending on the angles.
- 電気学会論文誌. A, 基礎・材料・共通部門誌 = The transactions of the Institute of Electrical Engineers of Japan. A, A publication of Fundamentals and Materials Society
電気学会論文誌. A, 基礎・材料・共通部門誌 = The transactions of the Institute of Electrical Engineers of Japan. A, A publication of Fundamentals and Materials Society 122(7), 664-669, 2002-07-01