Modeling and Dynamic Simulations of Doubly Fed Adjustable-Speed Pumped Storage Units

Coordinated Control of Distributed and Bulk Energy Storage for Alleviation of Post-Contingency Overloads

“…Originally, these units were used for daily energy management [31,32], while the newer adjustable speed system design allows PHS with a flexible ability to adjust their input and output power in the pumping mode as well, PHS can thus provide ancillary services (frequency regulation, contingency reserves, etc.) or support the integration of renewable energy sources, which greatly increases overall plant efficiency [18,29,33,34]. We only consider the PHS units with adjustable speed system for enhancing system corrective security.…”

Optimization of the start-up time of a variable speed pump-turbine unit in pumping mode

“…Among the papers dedicated to the study of the dynamic behavior of variable speed pump-turbine units [6]- [10], some ones [6]- [8] are focused particularly on the modeling of the hydraulic system and others [3], [9], [10] present detailed models of the electrical system including the control systems, but with simplified models of the hydraulic one. These different studies consider simplified models for the electrical system and do not take into account the converters.…”

Variable Speed Pumped Storage Hydropower Plants for Integration of Wind Power in Isolated Power Systems

“…Even more important is the possibility for power control in pumping mode, since traditional pump-turbines with synchronous machines connected directly to the grid will operate at constant speed and by that constant power in pumping mode. Variable speed operation has therefore been strongly motivated by the possibility to obtain similar power controllability in pumping mode as when operated as a generator (Lung et al, 2007;Schafer & Simond, 1998;Taguchi et al, 1991, Kuwabara et al, 1996. Another benefit by variable speed operation is that the allowable operation range in generator mode can be extended, and that problems with water hammering and other secondary effects in the turbine can be more easily controlled (Kuwabara et al, 1996;Gjengedal, 2001).…”

“…This topology was considered at an early stage of the investigations on variable speed pumped storage systems and has later been preferred in most large scale implementations to limit the converter ratings. With this concept, the industry has been able to build units with total ratings in the range of several hundreds of MVA (Gish et al, 1981;Hayashi et al, 1988;Lanese et al, 1995;Lung et al, 2007;Sugimoto et al, 1989;Taguschi et al, 1991). In addition to the reduced converter rating compared to the full scale current source converter, this configuration has as another advantage that the reactive power exchange with the grid can be controlled.…”