本論文提出一種用於分析直流分散式電源系統之在線式穩定度的隔離量測方法。基於直流分散式電源系統的匯流排導納，其品質因數可由穩定度分析圖求得，俾以分析其系統穩定度。
針對使用增益/相位分析儀的傳統量測方法而言，直接量測直流匯流排是相當危險的。基於安全考量，使用阻抗分析儀的隔離量測法被提出，俾以量測訊號側之導納。根據所測得之訊號側導納與所估測之介入網路阻抗，直流分散式電源系統的匯流排導納可被計算出，用以分析其系統穩定度。此外，基於阻抗分析儀之量測解析度，其精確度範圍可被求得，俾以定義隔離量測法的可信賴區域，以找出計算所得之匯流排導納的可信賴頻段。
最後，為了驗證隔離量測法之可信賴區域，分別使用阻抗分析儀與增益/相位分析儀對1歐姆電阻器進行隔離量測，以繪製其波德圖。此外，分別應用隔離量測法與傳統量測法於兩組不同之直流分散式電源系統上，俾以繪製其穩定度分析圖，以驗證隔離量測法用於直流分散式電源系統上之可行性。

This thesis presents the isolation measurement method for the on-line stability analysis of DC distributed power system (DPS). Based on the bus terminal admittance slope of DPS, the quality factor can be obtained from the stability analysis chart to analyze the system stability.
For the conventional measurement, it is quite dangerous to probe to the DC bus. The isolation measurement method is proposed to measure the signal-side admittance for safety consideration. With the measured signal-side admittance and characterized insertion network impedances, the bus terminal admittance can be calculated to analysis the system stability. Besides, based on the resolution of the meters in impedance analyzer, the accuracy range can be obtained to determine the reliable region for the calculated bus terminal admittance from isolation measurement.
Finally, in order to verify the reliable region of the isolation measurement method, a 1Ω resistor is measured by the isolation measurements using impedance analyzer and gain/phase analyzer to plot the Bode diagrams, respectively. Additionally, the isolation measurement method and conventional measurement method are applied to measure two different experimental DPSs, respectively, to plot their stability analysis charts to verify the feasibility of the isolation measurement for DPS.

[1] W. A. Tabisz, M. M. Jovanovic, and F. C. Lee, “Present and future of distributed power systems,” in Proc. lEEE APEC, Feb. 1992. pp. 11-18.
[2] E. W. Gholdston, K. Karmimi, and F. C. Lee, “Stability of large dc power systems using switch converters with application to the international space station,” in Proc. IECEC, Aug. 1996, pp. 166-170.
[3] J. Liu, X. Feng, F. C. Lee, and D. Boroyevich, “Stability margin monitoring for DC distributed power systems via perturbation approaches,” IEEE Transactions on Power Electronics, vol. 18, no. 6, pp. 1254-1261, NOV. 2003.
[4] P. Li and B. Lehman, “Accurate loop gain prediction for load DC-DC converters in on-board distributed power systems,” in Proc. IEEE APEC, vol. 2, 2004, pp. 1011-1017.
[5] G. S. Seo, J. Baek, K. Choi, H. Bae, and B. Cho, “Modeling and analysis of DC distribution systems,” in Proc. ICPE/ECCE, 2011, pp. 223–227.
[6] H. Zhang, F. Mollet, C. Saudemont, and B. Robyns, “Experimental validation of energy storage system management strategies for a local DC distribution system of more electric aircraft,” IEEE Trans. Ind. Electron., vol. 57, no. 12, pp. 3905–3916, Dec. 2010.
[7] H. Zhang, C. Saudemont. B. Robyns, N. Huttin, and R. Meruret, “Stability Analysis of the DC Power Distribution System of More Electric Aircraft,” in Proc. 13th Power Electronics and Motion Control Conference, Step. 2008, pp. 1523-1528.
[8] R. Ahmadi, P. Fajri, and M. Ferdowsi, “Performance improvement of a dc-dc converter feeding a telecommunication specific distributed power system using dynamic decoupling design,” in Proc. Telecommunications Energy Conference (INTELEC), Sept. 2012, pp. 1-7.
[9] C. M. Wildrick, F. C. Lee, B. H. Cho, and B. Choi, “A method of defining the load impedance specifications for a stable distributed power system,” IEEE Trans. Power Electron., vol. 10, no. 3, May 1995, pp. 280-285.
[10] X. Feng, Z. Ye, K. Xing, F. C. Lee, and D. Borojevic, “Impedance specification and impedance improvement for dc distributed power system,” in Proc. IEEE PESC, Jun. 1999, pp. 889-894.
[11] X. Feng, Z. Ye, K. Xing, F. C. Lee, and D. Borojevic, “Individual load impedance specification for a stable dc distributed power system,” in Proc. IEEE APEC, Mar. 1999, pp. 923-928.
[12] X. Wang, R. Yao, and F. Rao, “Three-step impedance criterion for small signal stability in two-stage dc distributed power systems,” IEEE Power Electron Lett., vol. 1, no. 3, pp. 83-87, Sept. 2003.
[13] X. Feng and F. C. Lee, “On-line measurement on stability margin of DC distributed power system,” in Proc. IEEE APEC, Feb. 2000, pp. 1190-1196.
[14] X. Feng, J. Liu, and F. C. Lee, “Impedance specifications for stable DC distributed power systems,” IEEE Trans. Power Electron., vol. 17, pp. 157-162, Mar. 2002.
[15] A. Riccobono and E. Santi, “Stability analysis of an all-electric ship MVDC power distribution system using a novel passivity-based stability criterion,” in Proc. IEEE ESTS., Apr. 2013, pp. 411-419.
[16] S. Abe, T. Ninomiya, M. Hirokawa, and T. Zaitsu, “Stability comparison of three control schemes for bus converter in distributed power system,” in Proc. PEDS, Nov. 2005, pp. 1244-1249.
[17] S. Abe, M. Hirokawa, T. Zaitsu, and T. Ninomiya, “Stability comparison of voltage mode and peak current mode control for bus converter in on-board distributed power system,” in Proc. Int. Telecommun., Sept. 2006, pp. 1-5.
[18] S. Abe, M. Hirokawa, T. Zaitsu, and T. Ninomiya, “Stability design consideration for on-board distributed power system consisting of full-regulated bus converter and POLs,” in Proc. IEEE PESC, June 2006, pp. 2669-2673.
[19] S. Abe, M. Hirokawa, M. Shoyama, and T. Ninomiya, T. “Optimal intermediate bus capacitance for system stability on distributed power architecture,” in Proc. IEEE PEMC, Sept. 2008, pp. 1-3.
[20] N. S. Nise, Control System Engineering, 5th ed. New York: John Wiley & Sons, Inc., 1982.
[21] E. C. Kuo, Automatic Control System, 5th ed. Englewood Cliffs, NJ: Prentice-Hall, 1982.
[22] Vatche Vorperian, “Simplified analysis of PWM converters using model of PWM switch part I: continuous conduction mode,” IEEE Trans. Aerosp. Electron. Syst., vol. 26, no. 3, pp. 490-496, May. 1990.
[23] R. B. Ridley, “A new continuous-time model for current-mode control,” IEEE Trans. Power Electron., vol. 6, no. 2, pp. 271-280, Apr. 1991.
[24] C. P. Basso, Switch-mode power supplies: SPICE simulations and practical designs, New York: McGraw-Hill, 2008.
[25] R. Erickson and D. Maksimovic, Fundamentals of Power Electronics, Kluwers Academic Press, 2001.
[26] Y. Panov and M. Jovanovic, “Practical issues of input/output impedance measurements in switching power supplies and application of measured data to stability analysis,” in Proc. 20th Annu. IEEE Appl. Power Electron. Conf. Expo., 2005, vol. 2, pp. 1339-1345.
[27] M. Liu, H. Yuan, Y. Sun, and C. Yang, “Research on measurement of DC power supply impedance,” in Proc. ICEMI, Aug. 16–19, 2009, pp. 2-703–2-706.
[28] Datasheets, “SV48-28-350-B: DC-DC Converter,” Acbel Polytech Inc., 2010. http://www.acbel.com/ProductFile/Spec-DC9001-000G.pdf
[29] Datasheets, “COE24120: DC-DC Converter,” Glary Power Technology. http://www.glary.com/PDF/2014/COE.pdf