بهبود عملکرد حفاظت مقايسه فاز در خطاهای با جريان اتصالی کوچک با استفاده از تخمين مؤلفه جريان بار
محورهای موضوعی : مهندسی برق و کامپیوترمجید صنایع پسند 1 , میثم جعفری نوکندی 2
1 - دانشگاه تهران
2 - دانشگاه تهران
کلید واژه: بازسازی مؤلفه اتصال کوتاهجريان اتصالیجريان بارحفاظت مقايسه فاز,
چکیده مقاله :
در خطاهاي با جريان اتصالي کوچک، جريان بار تأثير زيادي بر اختلاف فاز ميان جريان‌هاي دو سر خط دارد و حفاظت مقايسه فاز معمولاً قادر به تشخيص اين‌گونه خطاها نيست. در اين مقاله يک روش براي بهبود عملکرد مقايسه فاز در اتصالي‌هاي با جريان اتصالي کوچک پيشنهاد شده است. در روش پيشنهادي با تقريب‌زدن فازور جريان بار و کسر آن از جريان خطا، مؤلفه‌هاي واقعي جريان اتصال کوتاه به‌طور تقريبي بازسازي مي‌شوند و در نتيجه، روش پيشنهادي اختلاف فاز ناشي از جريان بار را تا حد زيادي حذف مي‌کند. از جريان قبل از خطاي خط به‌عنوان تخمين جريان بار در زمان اتصال کوتاه استفاده شده است. نشان داده شده است که اين فرض تقريبي در اتصالي‌هاي با جريان خطاي کوچک، عملکرد حفاظت مقايسه فاز را بهبود مي‌بخشد. ضمن آنکه روش پيشنهادي با افزايش حساسيت واحدهاي تشخيص وقوع خطا در رله‌ها، تعيين نوع خطا را نيز با دقت بيشتري امکان‌پذير مي‌سازد. روش پيشنهادي در يک سيستم نمونه شبيه‌سازي شده است. نتايج به‌دست آمده نشان‌دهنده بهبود قابل توجه عملکرد حفاظت مقايسه فاز با استفاده از روش پيشنهادي مي‌باشد.
Phase angle between the currents measured at the two ends of a protected transmission line could be highly affected by load current component for high resistance internal faults. As a result, the phase comparison protection (PCP) scheme might fail to recognize these kinds of faults. In this paper a new approach is proposed to enhance the accuracy of PCP scheme to detect such kind of faults. The fault component of current signal is reconstructed using the estimation of load component of the current signal under fault condition. Therefore, the proposed method eliminates the phase angle difference due to the load component. The pre-fault current of the line is used as the estimation of the load current component during the fault condition. It is shown that this approximation enhances the performance of PCP scheme for high resistance faults. It also increases the accuracy of classifying fault type due to increase of the sensitivity of fault detection units. The proposed method is simulated for a test system and is examined for various fault conditions. Obtained results show major improvement in the performance of PCP scheme.
[1]J. W. Dzieduszko, "Modern trends in line and network protection systems," in Proc.IEE Conf. Developments in Power System Protection , no. 479, pp. 177-180, Apr. 2001.
[2]J. A. Jiang, C. W. Liu, and C. S. Chen, "A novel adaptive PMU-based transmission line relay: design and EMTP simulation results,"IEEE Trans. Power Del., vol. 17, no. 4, pp. 930-937, Oct. 2002.
[3]D. Novosel, A. Phadke, M. M. Saha, and S. Lindahl, "Problems and solutions for microprocessor protection of series compensated lines,"in Proc.IEE Conf. Developments in Power System Protection,no. 434, pp. 18-23, Mar. 1997.
[4]A. A. Burzese, et al, "Pilot relaying performance analysis,"IEEETrans. Power Del., vol. 5, no. 1, pp. 85-102, Jan. 1990.
[5]Y. Ge, A. Wang, and H. Tao, "Phase-comparison pilot relays using fault superimposed components," in Proc. IEE Int. Conf. Adv. Power Syst. Contr. Oper. Manage., vol. 2, pp. 833-838, Nov. 1991.
[6]M. S. Sachdev, et al, "Advancements in microprocessor based protection and communication," IEEE Power Engineering Society,Tutorial Text, no. 97TP120-0, 1997.
[7]L. J. Ernst, W. L. Hinman, D. H. Quam, and J. S. Thorp, "Charge comparison protection of transmission lines: relaying concepts,"IEEE Trans. Power Del., vol. 7, no. 4, pp. 1834-1852, Oct. 1992.
[8]C. Cagnon and P. Gravel, "Extensive evaluation of high performance protection relays for the hydro-québec series comprnsated network," IEEE Trans. Power Del., vol. 9, no. 4, pp. 1799-1811, Oct. 1994.
[9]W. A. Elmore, "Current differential and phase comparison relaying compared with pilot distance schemes," inProc.25th AnnualWestern Protective Relay Conf., pp. 10-16, Oct. 1998.
[10]P. Ye, K. K. Li, D. S. Chen, and A. K. David, "Intelligent phase comparison carrier protection," in Proc.IEE Conf. Developments in Power System Protection, no. 434, pp. 295-298, Mar. 1997.
[11]S. Ward, "Phase comparison protection operating over power line carrier," in Proc.55th Texas A & M Conf. Protective Relaying Engineers , pp. 1-5, Apr. 2002.
[12]A. G. Phadke and J. S. Thorp,Computer Relaying for Power System,New York: John Wiley, 1988.
[13]M. S. Sachdev, T. S. Sidhu, I. Uttamachandani, and W. O. Kennedy,"Design of phase and amplitude comparators for transmission line protection," in Proc.IEEE Conf. on Communications, Power and Computing , pp. 179-184, May 1997.
[14]S. H. Horowitz and A. G. Phadke,Power System Relaying, 2nd ed.,London, U. K., Research Studies, 1995.
[15]A. T. Johns and S. K. Salman,Digital Protection for Power System ,U. K.: Peter Peregrinus, 1995.
[16]A. K. S. Chaudhary, K. S. Tam, and A. G. Phadke, "Protection system representation in the electromagnetic transient program," IEEE Trans. Power Del., vol. 9, no. 2, pp. 700-711, Apr. 1994.
[17]Y. Liao and S. Elangovan, "Digital distance relaying algorithm for first -zone protection for parallel transmission lines," in Proc.Inds. Elect. Eng. Gener. Transm. Distri. , vol. 145, pp. 531-536,Sept. 1998.
[18]R. K. Aggarwal and A. T. Johns, "A differential line protection scheme for power system based on composite voltage and current measurement,"IEEE Trans. Power Del., vol. 4, no. 3, pp. 1595-1601, Jul. 1989.
[19]L. Jie, S. Elangovan, and J. B. X. Devotta, "Adaptive travelling wave protection algorithm using two correlation functions,"IEEE Trans.Power Del., vol. 14, no. 1, pp. 126-131, Jan. 1999.
[20]M. Akke and J. S. Thorp, "Some improvements in the three –phase differential equation algorithm for fast transmission line protection,"IEEE Trans. Power Del., vol. 13, no. 1, pp. 66-72, Jan. 1998.
[21]C. K. Wong, C. W. Lam, K. C. Lei, C. S. Lei, and Y. Han, "Novel wavelet approach to current differential pilot relay protection,"IEEETrans. Power Del., vol. 18, no. 1, pp. 20-25, Jan. 2003.
[22]IEEE Power System Relaying Committee Working Group, "Single phase tripping and auto reclosing of transmission lines,"IEEE Committee Report, IEEE Trans. Power Del., vol. 7, no. 1, pp. 182-192, Jan. 1992.
[23]M. M. Saha, B. Kasztenny, E. Rosolowski, and J. Izykowski, "First zone algorithm for protection of series compensated lines,"IEEETran. Power Del., vol. 16, no. 2, pp. 200-207, Apr. 2001.
[24]T. S. Sidhu and M. Khederzadeh, "Series compensated line protection enhancement by modified pilot relaying schemes,"IEEE Trans. Power Del., vol. 21, no. 3, pp. 1194-1198, Jul. 2006.