在本論文中，研究發展一個對環境無感受性，多工的光纖電流感測系統。其中，以多工是以分時之技術，用以達成此研究的目標。理論推導及實驗結果，均在論文中呈現出來，實驗結果顯示其響應靈敏度接近56μV/A•turns，且訊雜比高達70dB。另外，在多工同時感測兩組電流，仍維持線性響應，多工感測之均一性誤差在2%之內。且無磁滯、飽和之限制，此性能足供電流感測系統，適用於大範圍電流變化值之量測。待測電流的波形亦可直接讀出，可作電力之電流品值監視。在這個研究裡，所完成的成果，可使光纖電流感測系統，在工業及電力傳輸線的電流監控上，邁向實際的應用。

In this essay, we developed an environmental immunity of multiplexed In-line sagnac interferometric fiber-optic current sensing system. The multiplexedwas used the time-division technique, were proposed to meet this research objective. The theoretical inference and experimental results were presented. The experimental results the system have sensitivity 56μV/A•turns, and the signal to noise ratio is 70dB. Besides, the multiplexed sensed two current in the same time, those two responses are still linearity. The uniform of these multiplex sensed are less than 2%. The system is hysteresis-free operator, no saturation limit. These features are suit for fiber-optic current sensor in measuring large range variable current. The current waveform can be read directly. In this research, the result let the fiber-optic current sensor approach to application on industrial power delivery line and monitor more current by this system.

摘要 I
誌謝 III
目錄 IV
表目錄 V
圖目錄 VI
符號表 IX
中英文對照表 XI
第一章 簡介 1
第二章 原理 5
2.1 感測光纖之電流響應模型 5
2.2 同軸桑克光纖干涉儀 9
2.3 系統響應之最佳化 13
2.4 光纖折射係數之感測效應 17
2.5 分時多工之應用 21
第三章 感測系統之設計 26
3.1 光纖光路 26
3.2 系統性能之提升 31
3.3 分時多工之構裝 34
第四章 實驗步驟與結果 38
4.1 光源對系統響應之影響 38
4.2 光纖特性對系統靈敏度之分析 40
4.3 光放大器在系統應用之探討 42
4.4 感測訊號之多工解調 44
第五章 結果討論 49
5.1 系統光源對訊號強度的關係 49
5.2 光纖對感測系統之效應 51
5.3 光放大器在系統應用之最佳化 53
5.4 感測系統分時多工之特性 55
第六章 總結 60
6.1 結論 60
6.2 未來發展 62
參考文獻 63
附表 66
附圖 72

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