Influence of the ratio of hybridization on the performances of synchronous generator with Hybrid Excitation

The Capability and Stability Domain curve of large Synchronous Generator provided with Hybrid Excitation system is analyzed in this paper. The machine consists of a conventional salient pole synchronous generator with additional surface mounted permanent magnets. For obvious reasons to limit time calculation Magnetic Equivalent Circuit (MEC) based on the use of RNM (Reluctances Network Model) method is used for modeling the generator. The performances of the generator, as function of hybridization rate, are investigated. An increase of hybridization ratio improves reactive power capability, reduces the machine volume. However an increase of magnetic material is a source of over cost that should be considered as an input data during the optimization process. The evolution of the active parts mass depending on number of turns per phase was investigated. The mass decreases when the number of turns increases but in expense of an increase in Joule losses.