Gas turbines inherently depict unique frequency response characteristics compared with other conventional synchronous generation technologies as their active power output is not entirely determined by the governor response during frequency deviations of the power network. Thus, gas turbine dynamics significantly influence on system stability during frequency events in power networks. Power system and power plant operators require improved understanding of the gas turbine characteristics during various frequency events in order to mitigate adverse impact on power system. Therefore a comparative analysis has been performed between combined-cycle gas turbines (CCGTs) and open-cycle gas turbines (OCGTs) in order to characterise the dynamic behaviour considering different types of frequency events in power networks. Study has shown that CCGTs result in significant frequency variations in power networks in comparison with OCGTs because of the temperature control action performed by the fast acting inlet guide vanes at the combustor. In particular, they are susceptible to lean blowout during large frequency increase events such as short-circuit faults in power networks. Furthermore, a case study was developed based on the New England-39 bus system in order to illustrate the impact of gas turbine dynamics on network frequency during short-circuit events in power networks.

References

1. 1)
  - 16. FRCC: ‘FRCC system disturbance and underfrequency load shedding event report’. 2008.
2. 2)
  - 7. Soon, K.Y., Milanovic, J.V., Hughes, F.M.: ‘Overview and comparative analysis of gas turbine models for system stability studies’, IEEE Trans. Power Syst., 2008, 23, (1), pp. 108–118 (doi: 10.1109/TPWRS.2007.907384).
3. 3)
  - 9. Tavakoli, M.R.B., Vahidi, B., Gawlik, W.: ‘An educational guide to extract the parameters of heavy duty gas turbines model in dynamic studies based on operational data’, IEEE Trans. Power Syst., 2009, 24, (3), pp. 1366–1374 (doi: 10.1109/TPWRS.2009.2021231).
4. 4)
  - 8. Hannett, L.N., Khan, A.H.: ‘Combustion turbine dynamic model validation from tests’, IEEE Trans. Power Syst., 1993, 8, (1), pp. 152–158 (doi: 10.1109/59.221261).
5. 5)
  - 18. System Operator Northern Ireland: ‘Minimum function specification for centrally dispatched OCGT units’. 2008.
6. 6)
  - 13. Doyle, J.: ‘Grid requirements on CCGT plants’ (CIGRE, 2012, Ireland).
7. 7)
  - 3. IEEE Working Group on Prime Mover and Energy Supply Models for System Dynamic Performance Studies: ‘Dynamic models for combined cycle plants in power system studies’, IEEE Trans. Power Syst., 1994, 9, (3), pp. 1698–1708 (doi: 10.1109/59.336085).
8. 8)
  - 4. Kunitomi, K., Kurita, A., Okamoto, H., et al: ‘Modeling frequency dependency of gas turbine output’. Proc. IEEE Power Engineering Society Winter Meeting, Columbus, USA, 2001.
9. 9)
  - 14. Meegahapola, L., Flynn, D.: ‘Frequency dynamics during high CCGT and wind penetrations’. Twenty-First Australasian Universities Power Engineering Conf. (AUPEC), Brisbane, Australia, 2011.
10. 10)
  - 2. Bagnasco, A., Delfino, B., Denegri, G.B., Massucco, S.: ‘Management and dynamic performance of combined cycle power plants during parallel and islanding operation’, IEEE Trans. Energy Convers., 1998, 13, (2), pp. 194–201 (doi: 10.1109/60.678985).
11. 11)
  - 2. Rowen, W.I.: ‘Simplified mathematical representations of heavy-duty gas turbines’, J. Eng. Power, 1983, 105, (1), pp. 865–869 (doi: 10.1115/1.3227494).
12. 12)
  - 10. Lalor, G., Ritchie, J., Flynn, D., O'Malley, M.J.: ‘The impact of combined-cycle gas turbine short-term dynamics on frequency control’, IEEE Trans. Power Syst., 2005, 20, (3), pp. 1456–1464 (doi: 10.1109/TPWRS.2005.852058).
13. 13)
  - 5. Kunitomi, K., Kurita, A., Tada, Y., et al: ‘Modeling combined-cycle power plant for simulation of frequency excursions’, IEEE Trans. Power Syst., 2003, 18, (2), pp. 724–729 (doi: 10.1109/TPWRS.2002.807112).
14. 14)
  - 1. Fox, B., Flynn, D., Bryans, L., et al: ‘Wind power integration: connection and system operation aspects’ (IET, London, UK, 2007).
15. 15)
  - 15. NERC Industry Advisory: ‘Turbine combustor lean blowout’. June 2008.
16. 16)
  - 20. PAL Turbine Services: ‘Turbine tips: root causes of high exhaust temperature spreads’, http://www.pondlucier.com/Company/tip.htm, accessed May 2013.
17. 17)
  - 17. IEEE Committee Report: ‘Computer representation of excitation systems’, IEEE Trans. Power Appar. Syst., 1968, 87, (3), pp. 1460–1464.
18. 18)
  - 19. System Operator Northern Ireland: ‘Minimum function specification for centrally dispatched CCGT units’. 2010.
19. 19)
  - 12. Kakimoto, N., Baba, K.: ‘Performance of gas turbine-based plants during frequency drops’, IEEE Trans. Power Syst., 2003, 18, (3), pp. 1110–1115 (doi: 10.1109/TPWRS.2003.814884).
20. 20)
  - 6. CIGRE Task Force: ‘Modeling of gas turbines and steam turbines in combined cycle power plants’, 2003.
21. 21)
  - 21. IEEE Standard 421.5-2005: ‘IEEE recommended practice for excitation system models for power system stability studies’. 2006.

Characterisation of gas turbine dynamics during frequency excursions in power networks

References

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