近年來，由於連接到電網的非線性負載快速增長，非線性負載消耗的電流具有較高的諧波含量，會影響負載穩定的運行。電力品質問題也歸因於電力系統中發生的不同故障情況，會導致系統中的電壓驟降或驟昇，從而損壞敏感性負載，因此本論文提出採用統一電力品質調節器結合超級電容器組，以改善配電系統中不良的電力品質。本論文之架構一研究了當市電端或負載端發生不良電力品質時，使用統一電力品質調節器結合超級電容器組之改善效果；架構二係以IEEE四節點之饋線系統為基礎，利用統一電力品質調節器結合超級電容器組來改善配電變壓器繞組為U-V/V-V連接、改變傳輸線R/X比例與負載大小所造成之電壓不平衡；架構三以實際台電配電系統為基礎，採用統一電力品質調節器結合超級電容器組來改善系統電壓不平衡，並觀察對系統中之再生能源發電系統之補償特性。由本論文之模擬結果，驗證所提出統一電力品質調節器結合超級電容器組於改善配電系統電力品質之可行性。

In recent years, due to the rapid growth of nonlinear loads connected to the power grid, the current consumed by the nonlinear loads has high harmonic content, which will affect the stable operation of the load. Power quality problems are also attributed to different fault conditions in the power system, which can cause voltage sags or swells in the system, thereby damaging sensitive loads, This thesis proposes a unified power quality conditioner integrated with a supercapacitor bank (UPQC-SC) to improve power quality problems such as current harmonics, voltage sags, swells, power harmonics and three-phase unbalance in the power distribution system. The UPQC-SC is first used to improve poor power quality occurred at the grid side or load side of system configuration 1. The UPQC-SC is then applied to system configuration 2 based on the IEEE four-node feeder system to improve the voltage unbalance caused by the UV/VV winding connections of the distribution transformers, changing the transmission line R/X ratio, and the size of the load. The proposed UPQC-SC is finally used to improve the voltage unbalance and characteristics of the renewable-energy power-generation systems of system configuration 3 based on the distribution system of Taiwan Power Company caused by the special winding connections of the distribution transformers. From the simulation results of three system configurations, the proposed UPQC-SC is feasible to improve power quality of distribution systems.

[1] J. Ye, H. B. Gooi, and F. Wu, “Optimal design and control implementation of UPQC based on variable phase angle control method,” IEEE Trans. Industry Informatics, vol. 14, no. 7, pp. 3109-3123, Jul. 2018.
[2] Y. Pal and A. Swarup, “A comparative analysis of UPQC-P, UPQC-Q and UPQC-VAmin - a simulation study,” in Proc. 2014 International Conference on Energy and Environment, Beijing, China, Jun. 26-27, 2014, pp. 80-85.
[3] S. K. Yadav, A. Patel, and H. D. Mather, “Comparison of power losses for different control strategies of UPQC,” in Proc. 2020 IEEE 9th Power India International Conference (PIICON), Sonepat, India, Feb. 28-Mar. 1, 2020, pp. 1-6.
[4] S. Devassy and B. Singh, “Design and performance analysis of three-phase solar PV integrated UPQC,” IEEE Trans. Industry Applications, vol. 54, no. 1, pp. 73-81, Jan./Feb. 2018.
[5] R. K. Patjoshi and K. Mahapatra, “High-performance unified power quality conditioner using command generator tracker-based direct adaptive control strategy,” IET Power Electronics, vol. 9, no. 6, pp. 1267-1278, Dec. 2015.
[6] C. Gong, R. Shi, Z. Chi, B. Zhang, L. Ma, and R. Jiao, “Research on application of UPQC in electric vehicle charging equipment,” Applied Mechanics and Materials, vol. 734, pp. 852-857, Feb. 2015.
[7] R. Pavani, T. S. Rao, and K. Mahapatra, “Design & simulation of energy storage unified power quality conditioner (EUPQC) for power quality improvement,” Journal of Engineering Research and Application, vol. 7, no. 5, pp. 29-35, May 2017.
[8] M. A. Mansor, K. Hasan, M. M. Othman, S. Z. B. M. Noor, and I. Musirin, “Construction and performance investigation of three-phase solar PV and battery energy storage system integrated UPQC,” IEEE Access, vol. 8, pp. 2169-3536, May 2020.
[9] C. K. Sundarabalan, Y. Puttagunta, and V. Vignesh, “Fuel cell integrated unified power quality conditioner for voltage and current reparation in four-wire distribution grid,” IET Smart Grid, vol. 2, no. 1, pp. 60-68, Mar. 2019.
[10] X. Xiao, J. Lu, C. Yuan, and Y. Yang, “A 10 kV 4 MVA unified power quality conditioner based on modular multilevel inverter,” in Proc. 2013 International Electric Machines & Drives Conference, Chicago, IL, USA, May 12-15, 2013, pp. 1352-1357.
[11] Y. Yang, X. Xiao, S. Guo, Y. Gao, C. Yuan, and W. Yang, “Energy storage characteristic analysis of voltage sags compensation for UPQC based on MMC for medium voltage distribution system,” Energies, vol. 11, no. 4, pp. 1-17, Apr. 2018.
[12] T. Koroglu, M. U. Cuma, A. Tan, M. Inci, T. Demirdelen, K. C. Bayindir, and M. Tumay, “Performance evaluation of a new hybrid unified power quality conditioner (HUPQC),” in Proc. 2015 IEEE 6th International Symposium on Power Electronics for Distributed Generation Systems (PEDG), Aachen, Germany, Jun. 22-25, 2015, pp. 1-6.
[13] N. Amaro and J. M. Pina, “Improved operation of an UPQC by addition of a superconducting magnetic energy storage system,” in Proc. 2015 9th International Conference on Compatibility and Power Electronics (CPE), Costa da Caparica, Portugal, Jun. 24-26, 2015, pp. 82-86.
[14] Y. Yang, X. Xiao, S. Guo, Y. Gao, C. Yuan, and W. Yang, “Control of UPQC based on steady state linear Kalman filter for compensation of power quality problems,” Chinese Journal of Electrical Engineering, vol. 6, no. 2, pp. 52-65, Jun. 2020.
[15] D. Somayajula and M. L. Crow, “An integrated dynamic voltage restorer-ultracapacitor design for improving power quality of the distribution grid,” IEEE Trans. Sustainable Energy, vol. 6, no. 2, pp. 616-624, Apr. 2015.
[16] Amirullah, Adiananda, O. Penangsang, and A. Soeprijanto, “A dual UPQC to mitigate sag/swell, interruption, and harmonics on three phase low voltage distribution system,” in Proc. 2020 Third International Conference on Vocational Education and Electrical Engineering (ICVEE), Surabaya, Indonesia, Oct. 3-4, 2020, pp. 1-6.
[17] J. Kotturu and P. Agarwal, “Comparative Performance Analysis of UPQC and open UPQC,” in Proc. 2015 Annual IEEE India Conference (INDICON), New Delhi, India, Dec. 17-20, 2015, pp. 1-6.
[18] M. Hasan, A. Q. Ansari, and B. Singh, “Parameters estimation of a series VSC and shunt VSC to design a unified power quality conditioner (UPQC),” in Proc. 2015 39th National Systems Conference (NSC), Greater Noida, India, Dec. 14-16, 2015, pp. 1-6.
[19] X. Luo, J. Wang, M. Dooner, and J. Clarke, “An integrated dynamic voltage restorer-ultracapacitor design for improving power quality of the distribution grid,” Applied Energy, vol. 137, no. 1, pp. 511-536, Jan. 2015.
[20] P. Prasad, M. K. Jainuddin, Y. Rambabu, and V. K. R. M. Rao, “Unified power quality conditioner (UPQC) with storage device for power quality problems,” International Journal of Engineering and Science, vol. 3, no. 8, pp. 19-26, Sep. 2013.
[21] 江榮城，電力品質實務(一)，台北市：全華科技圖書公司，民國八十九年五月。
[22] 電壓暫降產生的原因。 [Online]. Available: https://kknews.cc/z
h-tw/tech/kq24lp.html, retrieved date: Feb. 2, 2021.
[23] 李芸芬，南科園區鄰近線路遭雷擊之電壓驟降分析，崑山科技大學電機工程系碩士論文，民國九十四年六月。
[24] IEEE Std 1159-2019, IEEE Recommended Practice for Monitoring Electric Power Quality.
[25] 辜志承、沈混源、廖文彬、張源吉、蘇文，行政院國家科學委員會專題研究計畫：子計畫六：配電系統保護協調技術升級與效益研究(2/2)，執行期間民國92年8月1日至93年7月31日。
[26] 蔡明堂、林家宏、曹銘介、朱國瑞，機率神經網路應用於特定諧波偵測之研究，台電工程月刊，第676卷，第43-57頁， 民國93年12月。
[27] 廖柏翰，採用動態電壓恢復器結合超級電容器於配電系統電力品質之改善，國立成功大學電機工程學系碩士論文，民國一百零九年七月。
[28] 王耀諄、魏炫浚、李江瀚、林裕閔、周恭諒，行政院國家科學委員會專題研究計畫：感應發電機在不良操作條件下的電力品質分析(2/2)，執行期間民國95年8月1日至96年7月31日。
[29] 王耀諄，電力品質，第二版，台北市：高立圖書公司，民國九十八年八月。
[30] 劉威盛，配電型靜態同步補償器應用於變壓器U-V/V-V連接之電壓不平衡改善，國立成功大學電機工程學系碩士論文，民國一百零五年七月。
[31] 陳正一、黃子維、陳淑郡、藍建凱，「高效能並聯主動式濾波器參考補償電流控制策略於電力品質改善之研究(第3年)」，執行期間民國106年8月1日起至民國107年7月31日止，計畫編號：MOST 104-2628-E-008-004-MY3。
[32] 廖清榮，「赴美參加電力品質訓練課程與風力發電會議出國報告，台灣電力公司」，執行期間民國95年8月1日至96年7月31日。
[33] 辜志承、黃少俞， “風力發電機併網對配電系統電壓閃爍之影響” 中華民國電驛協會會刊24 期，民國90年。
[34] 許毓仁，電壓閃爍之分析與預測，國立中山大學電機工程學系博士論文，民國一百零一年七月。
[35] T.-H. Chen, J.-D. Chang, and Y.-L. Chang, “Models of grounded mid-tap open-wye and open-delta connected transformers for rigorous analysis of a distribution system,” IEE Proc. Generation, Transmission, and Distribution, vol. 143, no. 1, pp. 82-88, Jan. 1996.
[36] 盧修宇，採用多階靜態同步補償器於配電系統電壓不平衡改善之分析，國立成功大學電機工程學系碩士論文，民國一百零六年七月。
[37] P. C. Krause, O. Wasynczuk, and S. D. Sudhoff, Analysis of Electric Machinery and Drive Systems, 3rd ed., New York: John Wiley & Sons, 2013.
[38] U. S. Patel, M. D. Sahu, and D. Tirkey, “Maximum power point tracking using perturb & observe algorithm and compare with another algorithm,” International Journal of Digital Application & Contemporary Research (IJDACR), vol. 2, no. 2, pp. 1-8, Sep. 2013.
[39] S. J. Chapman, Electric Machinery Fundamentals, 4th ed., New York: McGraw-Hill, 2004.
[40] S. Heier, Grid Integration of Wind Energy Conversion Systems, New York: John Wiley & Sons, 1998.
[41] 吳登耀，多階串級H橋式靜態同步補償器應用於配電系統之三相電壓不平衡改善，國立成功大學電機工程學系碩士論文，民國一百零七年七月。
[42] L. Wang and G.-Z. Zheng, “Analysis of a microturbine generator system connected to a distribution system through power-electronics converters,” IEEE Trans. Sustainable Energy, vol. 2, no. 2, pp. 159-166, Apr. 2011.
[43] M.-J. Chen, Y.-C. Wu, and G.-T Liu, “Dynamic behavior a distributed incinerator power system under output power variation,” International Journal of Numerical Modelling Electronic Networks, Devices Fields, vol. 28, no. 1, pp. 65-77, Jan./Feb. 2015.
[44] O. Tremblay and L.-A. Dessaint, “Experimental validation of a battery dynamic model for EV applications,” World Electric Journal, vol. 3, no. 1, pp. 289-298, May 2009.
[45] T. Trapp, C. C. Chryssostomidis, and G. Karniadakis, “A design for the interface between a battery storage and charging unit and a medium voltage DC bus, as part of an integrated propulsion system in the all electric ship,” Grand Challenges in Modeling and Simulation (GCMS), Hague, Netherlands, Jun. 27-30, 2011, pp. 6-11.
[46] 薛儒鴻，負載端整合型電力品質調節器之設計及實現，國立台南大學電機工程學系碩士論文，民國一百年七月。
[47] A. K. Shah and N. Vaghela, “Shunt active power filter for power quality improvement in distribution systems,” International Journal of Engineering Development and Research (IJEDR), vol. 1, no. 2, pp. 23-27, May 2014.
[48] 陳俊丞，三相主動式電力濾波器在電力品質改善之研究，國立雲林科技大學電機工程學系碩士論文，民國九十六年七月。
[49] S. S. Dheeban and N. B. M. Selvan, “PV integrated UPQC for sensitive Load,” in Proc. 2020 International Conference on Emerging Trends in Information Technology and Engineering (ic-ETITE), Vellore, India, Feb. 24-25, 2020, pp. 1-7.
[50] G. Sivasankar and V. S. Kumar, “Supercapacitor energy storage based-UPQC to enhance ride-through capability of wind turbine generators,” Turkish Journal of Electrical Engineering & Computer Sciences, no. 23, pp. 1867-1881, Apr. 2014.