Determination of reactances of large hydro-generators using finite elements and domain decomposition

For an implementation of the finite element analysis in the design optimization of large synchronous machines, the efficiency of modeling and analysis methods is of crucial importance. The presented analysis method uses a domain decomposition algorithm, whereby only one finite element model for all angular rotor positions is necessary. Moreover, a significant reduction of the calculation time for successive rotor positions is established. These modeling and analysis methods are utilized for the determination and comparison with measurements of the steady-state reactances of a 500 MVA hydro-generator with 14 poles.