Pump Turbine Limberg 2 - Design Features and Efficiency Tests

Voith Hydro St. Pölten / Austria has been designed, manufactured, assembled and commissioned two pump turbines for the Austrian project Limberg 2, operated by theAustrian energy provider Verbund Hydro Power. Each pump turbine is providing a power of 240MW and is connected to the storagereservoirs Mooserboden and Wasserfallboden which provide a wide head range between 273m and 432m.This paper covers design features of the pump turbines based on the operationrequirements as well as considering constraints according the transport. A long and narrow access road to the cavern has resulted in a huge challenge for design,transport and assembling of the turbine components. This circumstance has led to asplit of many main components, like spiral case, head cover and bottom ring. Three parts of the spiral case have been lifted to the final position and welded together atplace, followed by heat treatment. Draft tube cone, bottom ring and the lower wicket gate bearings have free access from the bottom side, which allows dismantling therunner towards the lower side of the power plant. These requirements demand high engineering level in dimensioning and design of therelevant components as well as the usage of modern tools such as CFD and Finite Element calculations in combination with comprehensive fatigue evaluations. Thenecessary load spectrum for these assessments is an output of the transient simulation.After assembly, the turbine efficiency has been successfully proved by means of thermodynamic method in pump and turbine mode. Experiences from these tests andinstrumentation will be presented as well.

کلیدواژه ها:

Pump Turbine ، Verbund Hydro Power