本文探討利用快速傅立葉轉換與離散小波轉換計算各電力量，以及做電壓閃爍計算，比較兩方法計算結果之準確度，以期能應用於電力品質管制與改善。造成電力品質不良的來源繁多，例如非線性設備所產生的諧波、負載劇烈變動時所引起電壓變動及電壓閃爍。當電力品質低劣時，就供電端而言會造成供電品質的下降，則用電端易造成設備暫時的故障，或永久性的破壞。因此負載狀態之監控及量測是改善電力品質問題的首要工作，該如何建立有效且正確的數據分析是相當重要的。本論文採用快速傅立葉轉換及離散小波轉換法，先對負載之電壓及電流作頻譜資料的分析，並且根據IEEE Standard 1459-2010對電力量的定義，計算各定義下之電力數量，比較兩種方法之差異性，其絕對值百分誤差值都小於1。電壓閃爍也是電力品質其中一個重要的議題，本文採間接解調法與離散小波同步檢測法計算電壓閃爍，並且探討兩方法在不同頻段時所造成的影響，結果中發現，兩方法在某些頻段時會有各自較佳的準確度，若能將兩方法加以結合，可大大提升電壓閃爍分析之準確度。本論文各項計算結果除使用測試訊號分析外，也利用了現場實測資料作驗證，故各項研究數據都具有實用價值及可信度。

In this thesis, the Fast Fourier Transform (FFT) and the Discrete Wavelet Transform (DWT) are used to calculate the electric power values and the voltage flicker values. It is also to compare the accuracy of the two methods. There are many types of electrical devices which will reduce power quality. For examples, harmonic currents are generated by nonlinear devices, and voltage drop and voltage flicker are caused heavy fluctuating loads. From the point of view of the supply side, they will decline the quality of power supply in the same feeder. Then, from the point of view of customers, lower power quality may cause equipment malfunctions or even damage the device. It is the reason why the load monitoring and measurement become the top priority. Therefore, how to build an efficient and accurate method for analyzing data is important. In this thesis, the measurement data from an actual three-phase system are analyzed by using the DWT and the FFT. It calculates different types of power quantity according to the definitions in the IEEE Standard 1459-2010. From the comparison results of DWT and FFT, the absolute percentage error is less than 1. Voltage flicker is an important topic in power quality. In this thesis, the indirect demodulation method and the discrete wavelet synchronous detection method are used to calculate the values of voltage flicker. It is to discuss the impact in different frequency bands. In the results, it is observed that two methods have different accuracy in certain frequency bands. Therefore, if the two methods are combined, one can enhance the monitoring and analysis of voltage flicker. Simulation signals as well as field-measured data are used to provide study in the research of power quality.

[1] IEEE Recommended Practice and Requirements for Harmonic Control inElectric Power Systems, IEEE Standard 519-1992, 1993.
[2] IEEE Standard Definitions for the Measurement of Electric Power Quantities Under Sinusoidal, Nonsinusoidal, Balanced, or Unbalanced Conditions, IEEE Standard 1459-2010, 2010.
[3] Electromagnetic Compatibility (EMC), Part 3: Limits-Section 3: Limitation of Voltage Fuctuations and Flicker in Low-Voltage Power Supply Systems for Equipment With Rated Current 16A,IEC 61000-3-3, 1994.
[4] Electromagnetic Compatibility (EMC), Part 3: Limits-Section 5: Limitation of Voltage Fluctuations And Flicker in Low-Voltage Power Supply Systems for Equipment With Rated Current Greater Than16a, IEC 61000-3-5, 1994.
[5] 傅祖勳，「電力品質資料分析與壓縮」，博士學位論文，國立台灣科技大學電機工程系，2002。
[6] 陳裕仁，「煉鋼廠負載特性分析」，碩士學位論文，國立台灣科技大學，2000。
[7] D. C. Robertson, O. I. Camps, S. J. Mayer and W. B. Gish, “ Wavelets and electromagnetic power system transients,” IEEE Transactions on Power Delivery, vol. 11, no. 2, pp. 1050-1058, April, 1996
[8] IEEE Working Group on Nonsinusoidal Situations: Effects on Meter Performance and Definitions of Power, “Practical definitions for powers in systems with nonsinusoidal waveforms and unbalanced loads: a discussion,” IEEE Transaction on Power Delivery, vol. 11, no. 1, pp.79-101, April, 1996.
[9] IEEE Working Group on Nonsinusoidal Situations, “ A Survey of North American Electric Utility Concerns Regarding Nonsinusoidal Waveforms,” IEEE Transaction on Power Delivery, Vol. 11, No. 1, pp. 73-78, 1996.
[10] A. E. Emanuel, “ On the definition of power factor and apparent power in unbalanced polyphase circuits with sinusoidal voltage and current,” IEEE Transaction on Power Delivery, Vol. 8, No. 3, pp. 841-852, 1993.
[11] A. E. Emanuel, “Summary of IEEE standard 1459: definitions for the measurement of electric power quantities under sinusoidal, nonsinusoidal, balanced, or unbalanced conditions,”IEEE Transaction on Industry Applications, vol. 40, no. 3, pp. 869-876, 2004.
[12] H. Dalvand and V. G. Agelidis, “Real-time measurement of power quantities under sinusoidal and non-sinusoidal conditions for single-phase systems,” Proceeding of IEEE Energy Conversion Congress and Exposition (ECCE),Atlanta, GA, pp. 428-233, September, 2010
[13] I. D. Nicolae and P. M. Nicolae,“Using Discrete Wavelet Transform to evaluate power quality at highly distorted three-phase systems,” Proceeding of International Conference on Electrical Power Quality and Utilisation, Lisbon, pp. 1-6, October, 2011.
[14] S. Nath and P. Sinha,“Measurement of power quality under nonsinusoidal condition using wavelet and fuzzy logic,” Proceeding of International Conference on Power Systems, Kharagpur, pp.1-6, December, 2009.
[15] I. Daubechies, “Ten Lectures on Wavelets, ” Society for Industrial and Applied Mathematics, 1992.
[16] S. Kashyap and A. K. Singh, “Most Suitable mother wavelet for measurement of power system harmonics using DWT in view of IEEE standard 1459-2000,” Proceeding of International Conference on Harmonics and Quality of Power, Wollongong, New South Wales, pp. 1-6, October, 2008.
[17] X. X. Yang, and M. Kratz, “Power System Flicker Analysis by RMS Voltage Values and Numeric Flicker Meter Emulation,” IEEE Transaction on Power Delivery, vol. 24, no. 3, July, 2009.
[18] M. Poormonfaredazimi, H. Moghadam, and A. Doroudi,“A novel method to trace flicker sources,” Proceedings of 17th Conference on Electrical Power Distribution Networks (EPDC), Tenran, pp. 1-7, May, 2012.
[19] D. Zhu, Qing-Wei Gao, Yi-xiang Lu, Dong Sun and Ling-dong Li,“A novel method for voltage flicker extraction of power systems, ”International Conference on Electrical and Control Engineering (ICECE), Yichang, September, 2011
[20] 江國銘，「以FPGA為設計晶片之電壓閃爍計算」，碩士學位論文，國立台灣科技大學電機工程系，民國100年。
[21] 黃鎮平，「負載特性對功率因數計算值的影響」，博士學位論文，國立台灣科技大學電機工程系，2010。

[22] 江榮城，電力品質實務(一)，台北，全華科技圖書股份有限公司，2000。
[23] 李廷祥，「目前的電力問題：電力品質」，第十四屆電力工程研討會演講稿，第18頁，1993。
[24] 辜志承、吳啟瑞、江榮城，「高壓端電壓閃爍源對低壓用戶之影響」，台灣電力綜合研究所，專題研究計劃報告，1994。
[25] 陳冠宏，「以混沌理論文基礎之電壓閃爍預測」，碩士學位論文，國立中山大學，2008
[26] 鍾崇訓，「使用FPGA晶片之電壓閃爍計算」，碩士學位論文，國立台灣科技大學電機工程系，2010。
[27] J. J. Trageser, “Power usage and electrical circuit analysis for electric arc furnaces,” IEEE Transaction on Industry Applications, vol. IA-16, no.2, pp. 277-284, March, 1980
[28] 吳啟瑞、李兆惠、顏世雄、劉志放、郭宗益、江榮城、鄭久男、許哲揚、關錦龍，「161kV級大型鋼鐵廠電力品質特性分析」，台電電力綜合研究所，研究計畫報告，1995。
[29] 黃哲文譯著，電爐煉鋼學，高雄，前程出版社，1988。
[30] 關錦龍，「最大視在電力變動法應用於電壓閃爍之分析」，博士學位論文，國立台灣科技大學電機工程系，2003。
[31] 董長虹、高志、於嘯海，「小波分析工具箱原理與應用」，國防工業出版社，2004
[32] 許峯豪，「基於心臟收縮陣列之小波-Hilbert轉換整合及其FPGA實現應用電力品質訊號監測」，國立成功大學，2008
[33] 王奕捷，「低壓線路串聯電弧故障時域及頻域分析與檢測」，國立台灣科技大學，2012
[34] W. G. Morsi, and M. E. El-Hawary, “Reformulation power components definitions contained in the ieee standard 1459-2000 using discrete wavelet transform,” IEEE Transaction on Power Delivery, vol. 22, no. 3, 2007
[35] W. K. Yoon and M. J. Devaney, “Reactive power measurement using the wavelet transform, ” IEEE Transactions on Instrumentation and Measurement, vol. 49, no. 2,2000
[36] G. S. Kumar, D. V. S. Sarma and C. Venkatesh, “Wavelet transform based Harmonic analysis and real power measurement” Proceeding of the India International Conference on Power Electronics, New Delhi, pp. 1-6, January, 2011
[37] Marple, S. L., “Computing the discrete-time analytic signal via FFT, ” IEEE Transactions on Signal Processing, vol. 47, No.9, pp. 2600-2603, September, 1999.
[38] 黃新維，「應用包絡檢測法於電壓閃爍量測之研究」，國立清華大學，2006
[39] W. Zhou, L. Lin, X. Ye and W. Gu, “Wavelet transform based new methods for voltage flicker signal and harmonic detection,” Proceeding of the IEEE International Conference on Power Electronics and Drive System, Singapore, vol. 1, pp. 805-810, November, 2003