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Accurate clock synchronization for power systems protection devices over packet switched networks

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Computer Science - Research and Development

Abstract

Channel based clock synchronization in packet switched networks (PSNs) is considered for, but not limited to, the time and safety/security critical application of power system protection. The synchronization accuracy requirement of power system protection devices used for line current differential protection is \(10\,\upmu \)s, which could be achieved in time division multiplexing networks that were traditionally used in that domain. In PSN, highly accurate synchronization can be achieved with the standard synchronization method IEEE 1588-2008 Precision Time Protocol (PTP) when devices in the communication network are equipped with so called boundary clocks (BCs) or transparent clocks (TCs). However, when BCs or TCs are not available, the required accuracy can hardly be achieved. In this work, a modification of the PTP is proposed that replaces the clock parameter estimation and the computation of the clock control signal. Thereby, the statistics of measured packet delays are considered to select optimum estimation schemes. It is shown that the here proposed method outperforms the Linux PTP in terms of timing accuracy by a factor of 2 in enterprise local area networks and by a factor of 10 in Carrier Ethernet wide area networks.

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References

  1. Ahmad A, Zennaro D, Serpedin E, Vangelista L (2012) A factor graph approach to clock offset estimation in wireless sensor networks. IEEE Trans Inf Theory 58(7):4244–4260

    Article  MathSciNet  Google Scholar 

  2. Aichhorn A, Mayrhofer R, Krammer H, Kern T (2016) Realization of line current differential protection over IP-based networks using IEEE 1588 for synchronous sampling. 13th IET international conference on developments in power system protection

  3. Bartel D, Etzlinger B, Springer A (2014) Distributed clock synchronization and ranging in time-variant wireless networks. In: Proceedings of ICASSP-14, pp 5744–5748

  4. Brown DR, Klein AG (2013) Precise timestamp-free network synchronization. In: Proceedings of CISS-13. Baltimore, MA

  5. Bullock JB, King TM, Kennedy HL, Berry ED, Zanfino G (1997) Test results and analysis of a low cost core gps receiver for time transfer applications. In: Frequency control symposium, 1997. Proceedings of the 1997 IEEE international, pp 314–322

  6. Choi BK, Moon S, Zhang ZL, Papagiannaki K, Diot C (2004) Analysis of point-to-point packet delay in an operational network. In: Proceedings of IEEE INFOCOM, vol 3, pp 1797–1807

  7. Communication networks and systems in substations—part 1: introduction and overview. IEC/TR 61850-1 (2003)

  8. Communication networks and systems for power utility automation—part 90-1: use of IEC 61850 for the communication between substations. IEC/TR 61850-90-1 (2010)

  9. Dierks A, Worthington I, Olivier P (1997) Gps synchronised end-to-end tests of transmission line teleprotection schemes in the eskom network. In: Sixth international conference on developments in power system protection (Conf. Publ. No. 434), pp 355–360

  10. Etzlinger B, Wymeersch H, Springer A (2014) Cooperative synchronization in wireless networks. IEEE Trans Signal Process 62(11):2837–2849

    Article  MathSciNet  Google Scholar 

  11. Fukushima S, Yamada J, Mori T, Kawano F, Okamura H, Kohiga S, Yamakawa H (2014) Development of line current differential relay over native ethernet. In: 12th IET international conference on developments in power system protection. Toshiba Corp, Kawasaki

  12. Giorgi G, Narduzzi C (2011) Performance analysis of Kalman-filter-based clock synchronization in IEEE 1588 networks. IEEE Trans Instrum Meas 60(8):2902–2909

    Article  Google Scholar 

  13. Holleczek T, Venus V, Naegele-Jackson S (2009) Statistical analysis of IP delay measurements as a basis for network alert systems. In: ICC ’09, 2009 IEEE international conference on communications, pp 1–6

  14. Humphreys TE, Ledvina BM, Psiaki ML, OHanlon BW, Kintner PM Jr (2008) Assessing the spoofing threat: development of a portable gps civilian spoofer. In: Proceedings of the ION GNSS international technical meeting of the satellite division, vol 55, p 56

  15. IEEE (2008) IEEE Standard for a Precision Clock Synchronization Protocol for Networked Measurement and Control Systems. IEEE Std. 1588-2008

  16. Jesus J (2014) MPLS networks for inter substation communication for current differential protection applications in digital substations. PAC World Conference, Zagreb Croatia

  17. Kay SM (1993) Fundamentals of statistical signal processing: estimation theory. Prentice-Hall, Upper Saddle River

    MATH  Google Scholar 

  18. Klepczynski W, Ward P (2000) Frequency stability requirements for narrow band receivers. 32nd Annual precise time and time interval (PTTI) meeting

  19. Leng M, Wu YC (2010) On clock synchronization algorithms for wireless sensor networks under unknown delay. IEEE Trans Veh Technol 59(1):182–190

    Article  Google Scholar 

  20. Leng M, Wu YC (2011) Low-complexity maximum-likelihood estimator for clock synchronization of wireless sensor nodes under exponential delays. IEEE Trans Signal Process 59(10):4860–4870

    Article  MathSciNet  Google Scholar 

  21. Li J, Jeske DR (2009) Maximum likelihood estimators of clock offset and skew under exponential delays. Appl Stoch Model Bus Ind 25(4):445–459

    Article  MathSciNet  MATH  Google Scholar 

  22. Noh KL, Chaudhari QM, Serpedin E, Suter BW (2007) Novel clock phase offset and skew estimation using two-way timing message exchanges for wireless sensor networks. IEEE Trans Commun 55(4):766–777

    Article  Google Scholar 

  23. Papagiannaki K, Moon S, Fraleigh C, Thiran P, Tobagi F, Diot C (2002) Analysis of measured single-hop delay from an operational backbone network. In: Proceedings of IEEE INFOCOM, vol 2, pp 535–544

  24. PTP IEEE 1588 stack for Linux (2016). http://linuxptp.sourceforge.net

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Acknowledgments

This research is performed within the research project SmartProtect, supported by The Austrian Research Promotion Agency (FFG), Project No. 848911. Part of this work was supported by the Linz Center of Mechatronics (LCM) in the framework of the Austrian COMET-K2 programme. The authors gratefully acknowledge the possibility of using the communication network of the utility company Energie AG Oberoesterreich Telekom GmbH to be able to make tests in an active communication environment.

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Correspondence to Andreas Aichhorn.

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Aichhorn, A., Etzlinger, B., Mayrhofer, R. et al. Accurate clock synchronization for power systems protection devices over packet switched networks. Comput Sci Res Dev 32, 147–158 (2017). https://doi.org/10.1007/s00450-016-0302-y

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  • DOI: https://doi.org/10.1007/s00450-016-0302-y

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