歸航臺天線對鄰近架空電力線及通信線之電磁干擾

Electromagnetic Interferences on Nearby Overhead Power and Telephone Lines from the Antenna of the Radio Navigation Station

本文探討歸航台天線所發射之導引訊號對鄰近架空電力線及通信線所引起的電磁干擾問題，其中部份電氣設施受到影響而導致功能失效或毀損。本研究首先在現場實測了電磁干擾的耦合訊號，並分析干擾信號的組成成分，其次為了探討耦合感應的干擾途徑，乃建立一小段架空線來進行耦合干擾特性測量，進而研擬改善對策，並由適當的干擾抑制措施，如濾波、屏蔽與減少線間電磁耦合之面積等，來降低電源線及電話線上的干擾耦合電壓，使歸航台內設備可以恢復正常功能。

This paper is to explore the problems of the electromagnetic interferences (EMI) generated by the guiding signals from antenna of the radio navigation station on nearby overhead power and telephone lines. Part of the electrical facilities were malfunctioned or destroyed by the EMI. In this study, firstly, the EMI signals were measured. Next, a small section of the overhead line was built to perform the measurements for the coupling-inductive interference phenomena and to explore the paths of the interference. Furthermore, methods to mitigate the EMI’s were also proposed and applied, such as filter, shield and reduction for the electromagnetic coupling-area. So interference voltages on the power and telephone lines were reduced significantly. Thus, the devices in the radio navigation station are functioning normally.