On the Implementation of Variable Speed in Pump-Turbine Units Providing Primary and Secondary Load-Frequency Control in Generating Mode

This paper analyses different control strategies for the speed control loop of a variable-speed pump-turbine unit equipped with a doubly fed induction generator, operating in generating mode in an isolated power system with high penetration of intermittent renewable energy. The control strategies are evaluated and compared to each other in terms of the amount of water discharged through the pump-turbine and of the wicket gates fatigue while providing primary and secondary load-frequency control. The influence of the penstock length and the initial operating point on the performance of each control strategy is studied in detail. For these purposes, several simulations have been performed with a suitable dynamic model of the pumped-storage hydropower plant and the power system. The results of the paper indicate that a proper control strategy would consist in updating the reference speed according to the power generation schedule and keeping it constant within each scheduling period (typically 1 h).

[1]  Kjetil Uhlen,et al.  Variable speed pumped storage hydropower for integration of wind energy in isolated grids : case description and control strategies , 2008 .

[2]  Armando Carravetta,et al.  PAT Efficiency Variation with Design Parameters , 2014 .

[3]  Ying Lu,et al.  Modeling and Dynamic Simulations of Doubly Fed Adjustable-Speed Pumped Storage Units , 2007, IEEE Transactions on Energy Conversion.

[4]  Allen J. Wood,et al.  Power Generation, Operation, and Control , 1984 .

[5]  P. Kundur,et al.  Power system stability and control , 1994 .

[6]  Janusz Bialek,et al.  Power System Dynamics: Stability and Control , 2008 .

[7]  Julio Usaola,et al.  Incidence on Power System Dynamics of High Penetration of Fixed Speed and Doubly Fed Wind Energy Systems: Study of the Spanish Case , 2002, IEEE Power Engineering Review.

[8]  Houria Siguerdidjane,et al.  Nonlinear control with wind estimation of a DFIG variable speed wind turbine for power capture optimization , 2009 .

[9]  G. Sheblé,et al.  Power generation operation and control — 2nd edition , 1996 .

[10]  Hongxing Yang,et al.  Technical feasibility study on a standalone hybrid solar-wind system with pumped hydro storage for a remote island in Hong Kong , 2014 .

[11]  K. R. Padiyar,et al.  Power system dynamics : stability and control , 1996 .

[12]  Juan I. Pérez-Díaz,et al.  Contribution of a hydraulic short-circuit pumped-storage power plant to the load–frequency regulation of an isolated power system , 2014 .

[13]  Luis Rouco,et al.  Modeling of thermal generating units for automatic generation control purposes , 2004, IEEE Transactions on Control Systems Technology.

[14]  J.A. Suul,et al.  Wind power integration in isolated grids enabled by variable speed pumped storage hydropower plant , 2008, 2008 IEEE International Conference on Sustainable Energy Technologies.

[15]  Hanif M. Chaudhry,et al.  Applied Hydraulic Transients , 1979 .

[16]  N. D. Hatziargyriou,et al.  Frequency Control in Autonomous Power Systems With High Wind Power Penetration , 2012, IEEE Transactions on Sustainable Energy.

[17]  Juan I. Pérez-Díaz,et al.  Dynamic response of hydro power plants to load variations for providing secondary regulation reserves considering elastic water column effects , 2012 .

[18]  David A. Bradley,et al.  Reproducing oscillatory behaviour of a hydroelectric power station by computer simulation , 2000 .

[19]  D. Lefebvre,et al.  COMBINED DETAILED AND QUASI STEADY-STATE TIME SIMULATIONS FOR LARGE-DISTURBANCE ANALYSIS , 2006 .

[20]  Istvan Erlich,et al.  DYNAMIC BEHAVIOR OF VARIABLE SPEED PUMP STORAGE UNITS IN THE GERMAN ELECTRIC POWER SYSTEM , 2002 .

[21]  T. Van Cutsem,et al.  Quasi steady-state models for long-term voltage and frequency dynamics simulation , 2005, 2005 IEEE Russia Power Tech.

[22]  Christophe Nicolet,et al.  Investigation of Control Strategies for Variable-Speed Pump-Turbine Units by Using a Simplified Model of the Converters , 2010, IEEE Transactions on Industrial Electronics.

[23]  Guillermo Martínez-Lucas,et al.  Stability Analysis of a Run-of-River Diversion Hydropower Plant with Surge Tank and Spillway in the Head Pond , 2014, TheScientificWorldJournal.

[24]  John K. Kaldellis,et al.  Optimal wind-hydro solution for Aegean Sea islands' electricity-demand fulfilment , 2001 .

[25]  John S. Anagnostopoulos,et al.  Simulation and size optimization of a pumped–storage power plant for the recovery of wind-farms rejected energy , 2008 .

[26]  Guillermo Martínez-Lucas,et al.  Power-frequency control of hydropower plants with long penstocks in isolated systems with wind generation , 2015 .

[27]  J. Kaldellis,et al.  Evaluation of the wind–hydro energy solution for remote islands , 2001 .

[28]  Jan Pierik,et al.  Inertial response of variable speed wind turbines , 2006 .

[29]  Akihiko Yokoyama,et al.  Load frequency control using distributed batteries on the demand side with communication characteristics , 2012, 2012 3rd IEEE PES Innovative Smart Grid Technologies Europe (ISGT Europe).

[30]  K R Padiyar,et al.  Power System Dynamics , 2002 .

[31]  Christophe Nicolet,et al.  Benefits of Variable Speed Pumped storage Units in Mixed Islanded Power Network during Transient Operation , 2009 .

[32]  Vijay Vittal,et al.  The impact of increased penetration of converter control-based generators on power system modes of oscillation , 2015, 2015 IEEE Power & Energy Society General Meeting.