76. Modern Tolls and Practices for Large Hydro-Generator Design Merkhouf A., Karmaker H., McLaren D., Ferguson J., Bouri B., Benchaita L., Li Y. (Proceedings, Hydro 2003, Vol. I, Croatia, pp. 565–571). Abstract In the design process of large electrical machines, numerous tradeoffs between conflicting requirements are involved. Therefore, modern computer tools and clear design practices are of paramount importance in achieving competitive robust designs. GE Hydro has introduced many modern design tools with embedded optimization techniques that allow engineers to explore a large number of design possibilities in a short time optimize the design for each customers’ needs. Recently, a permeance model has been developed by using combined analytical and magneto-static finite element solutions with one pole pitch model. The method has been applied to large hydrogenerator with fractional slot stator windings. This novel method makes the computational algorithm very fast compared to time-stepping solutions. This new analysis tool has also proven to be very powerful in analyzing the sources of vibration frequencies and mode shapes and in the negative sequence heating studies. The new automated design optimization process introduced by GE Hydro is able to perform trade-off and design sensitivity studies to determine the benefit of modifying design constraints and improving enabling technologies. The use of electromagnetic finite element codes for the design phase of hydroelectric generators has been described. Special emphasis has been laid on time step finite element program and on the new software tool for steady state time-harmonic field solution in salient pole synchronous machines based on a permeance and MMF model. The latter requires considerably less CPU time than the full timestepping finite element simulations. The wave program shows promising results for applications to machines with fractional slot windings requiring prohibitive amounts of computing resources for timestepping finite element solutions. New analysis capabilities for thrust bearings provide accurate predictions of bearing performance and enables determination of the influence of individual parameters such as segment thickness. This has resulted in improvement in both the performance and in load capabilities of our thrust bearings. The use of CFD modeling for the purpose of an improved generator cooling is an appropriate method to get the required information such as temperature; pressure differences and heat transfer coefficients. The predictions of these parameters using CFD method are specifically more important in fluid regions that contain a complex geometry and difficult airflow conditions. Top Keywords Design process, Tradeoffs, Conflicting requirements, Robust designs, Optimization techniques, Permeance model, Magneto-static. Top |