應用混合差分進化法於電壓穩定及諧波失真改善

本論文為應用混合差分進化法於電力系統電壓穩定度及諧波失真最佳化改善之研究，論文分為兩大部分，第一部分以最佳化虛功率補償裝置設定提升電壓穩定度；另一部分以最佳化被動濾波器設計減少電力系統諧波失真。本論文首先發展一個改良型電壓穩定度指標，接著以此指標求取最佳虛功率補償裝置的設計，能有效提高系統電壓穩定度及減少線路損失，同時使用混合差分進化法(HDE)來解決最佳化問題，包括決定最佳的變壓器有載接頭切換器設定、發電機或同步調相機的激磁設定及靜態虛功率補償器的安裝位置與容量設定，進而調整虛功率潮流並提供最佳電壓穩定度。接著本文以IEEE 30-Bus及118-Bus兩電力潮流測試系統來驗證本論文所提出之方法的效能。結果證明本文所提出的改良型電壓穩定度指標及採用之最佳化方法能夠有效改善系統的電壓穩定度及減少線路損失。電力諧波問題的改善，考慮系統阻抗、諧波電流源及濾波器諧振點皆為可變動的值，使用混合差分進化法求解最佳化被動濾波器設計。其目的為求解最小諧波電流及電壓失真，於固定成本下選擇濾波器型式、決定最佳濾波器參數及諧振點。在電力系統中諧波電流及電壓被表示為機率模式，並使用統計模擬法求解，再用蒙地卡羅模擬來驗證機率模式的準確性。這個方法應用於求解實際化工廠諧波問題，結果驗證本論文所提出的被動濾波器的設計，可適用於實際化工廠及工業配電系統。

關鍵字

被動濾波器；改良型電壓穩定度指標；虛功率補償器；電壓穩定度；混合差分進化法；諧波失真；諧振點

並列摘要

This dissertation applies the hybrid differential evolution to the improvement of voltage stabitity and harmonic distortion for power systems. Two parts are included in this research, one is optimal setting of reactive compensation devices with an improved voltage stability index for voltage stability enhancement. The other one is optimal planning of passive harmonic filters for harmonic mitigation. Firstly, this research proposes an improved voltage stability index ( ) for voltage stability enhancement of both radial and network power systems, and then applies this improved voltage stability index to reactive compensation devices settings. To solve the optimization problem, this work introduces the hybrid differential evolution (HDE) to determine optimal tap settings of on-load tap changing (OLTC) transformers, excitation settings of generators or synchronous condensers (SCs), and locations with sizes of static var compensators (SVCs). The performance of the proposed method is verified using the IEEE 30-Bus and 118-Bus power flow test systems. The results show that the proposed method using the improved voltage stability index and the optimization method is able to effectively enhance voltage stability of a system and reduce line losses. Secondly, this research presents an optimal planning of passive harmonic filters using the hybrid differential evolution (HDE) method considering variation of system impedance, harmonic current sources and filter tuning points. The proposed method minimizes an objective function composed of the total harmonic distortion of current and voltage, selects different filters topologies, and determines their optimal parameters and tuned points under a constant cost. The harmonic currents and voltages in a power system are expressed as probabilistic models which are obtained using the statistical simulation method. Monte Carlo simulation is employed to verify the accuracy of the obtained probabilistic models. The method proposed is applied to solve the harmonic problems in a practical chemical plant, and the results show that the proposed method is effective for passive filter planning in industrial distribution systems.

並列關鍵字

passive harmonic filter ； improved voltage stability index ； reactive power compensation ； voltage stability ； hybrid differential evolution (HDE) ； harmonic distortion ； tuned points

參考文獻

[1] C. C. Liu and K. T. Vu, “Analysis of tap-changer dynamics and construction of voltage stability regions,” IEEE Transactions on Circuits and Systems, Vol. 36, pp. 575- 590, Apr. 1989.

[2] D. Popovic, I. A. Hiskens, and D. J. Hill, “Investigations of load tap changer interaction,” Electrical Power Energy Systems, Vol. 18, pp. 81-97, 1996.

[3] T. X. Zhu, S. K. Tso, and K. L. Lo, “An investigation into the OLTC effects on voltage collapse,” IEEE Transactions on Power Systems, Vol. 15, pp. 515 – 521, May 2000.

[4] C. Vournas and M. Karystianos, “Load tap changers in emergency and preventive voltage stability control,” IEEE Transactions on Power Systems, Vol. 19, pp. 492-498, Feb. 2004.

[5] A. M. Chebbo, M. R. Irving, and M. J. H Sterling, “Voltage collapse proximity indicator: behaviour and implications,” IEE Proceedings of Generation, Transmission and Distribution, Vol. 139, pp. 241-252, May 1992.

國際替代計量

應用混合差分進化法於電壓穩定及諧波失真改善

未授權

主題瀏覽