本論文提出一直流分散式電源系統的在線式穩定度分析。在大規模的分散式電源系統下，基於傳統的穩定度分析法，注入一電流源，難以量測所有的電源電流與負載電流去計算出阻抗比值，分析其系統之穩定度。然而，直流匯流排之端點阻抗可輕鬆從匯流排電壓與注入電流之比值獲得。
係基於電源轉換器之直流匯流排的RLC並聯等效電路，俾以推導其匯流排阻抗之斜率的轉移函數，俾以提供對應的波德圖與奈氏圖，以阻抗斜率為基礎之系統穩定度的分析準則。
最後實驗單一降壓轉換器與並聯兩組降壓轉換器，俾以驗證本論文提出以阻抗斜率為基礎之系統穩定度分析。

This thesis presents the on-line stability analysis of DC distributed power system (DPS). It is difficult to measure all the source and load currents for the calculation of the impedance ratio for the conventional methods to analyze the system stability of large-scale DPSs injected with a current source. However, the bus terminal impedance can be easily obtained from the ratio of the DC bus voltage to the injected current at the DC bus. Based on the derived parallel RLC equivalent circuits of the bus terminal impedance for the conventional power converters, the transfer function of the bus terminal impedance slope can be derived to develop the criterion for the analysis system stability according to the corresponding Bode and Nyquist diagrams.
Finally, the experiments with a single buck converter and two buck converters in parallel are conducted to verify the proposed criterion using bus terminal impedance slope for the system stability analysis.

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