Research and Development
A wide variety of very advanced hydraulic designs has been developed in connection with recent contracts. In the field of Francis turbines, the new generation of runner designs was the key to successful upgrade projects ranging from high head runners in Norway to large 770 MW runners in Venezuela.
In the field of low head units, new axial runners for existing units with special casing designs have been developed. The optimization of runner casing interaction has also been the key success factor in the upgrading of Pelton units.
Continuous research in numerical design has also enabled further progress in the field of single-stage and multi-stage pump turbines.
Very attractive synergy potentials have been identified and already exploited between the hydraulic designs of large tailor-made pumps for water transport and the designs for pump-turbines and pumps for storage power plants.
A further interactive R&D initiative has been launched with respect to the field assessment of existing hydro plants, both from the mechanical and the electrical point of view.
New developments for high-voltage insulation and a cost-effective design were successfully introduced for hydro generators, as well as for turbo generators. Further research activities on large rotating electrical machines with high rated voltage were focused on the optimization of the stator end winding design regarding corona phenomena.
For the cooling of high-performance (maximum-capacity) bulb-type generators, an innovative ventilation system was developed, which provides several advantages for the mechanical and electrical design. The ventilation design is based upon numerical fluid dynamics (CFD) and measurements.
Detailed CFD simulations were carried out in order to investigate the oil flow and mixing behavior in the cavities between adjacent thrust bearing pads.
Another focus of R&D was placed on technologies in the field of automation. The new SAT 250 product line represents a state-of the art system for control centers and operator stations. For excitation and protection systems, the development of new platforms has been launched. The application of the very successful technology for governors and plant controls has been extended to all kinds of turbine types and sizes.
The large pumps program was extended by Francis pumps. The development program further includes extensions for and improvement of semi-axial and axial pumps, the latter as bulb pumps. Other main points in the development program include materials and coating for components sensitive to wear, shaft bearing assembly, and rotor dynamics for main coolant pumps.