Analysis of synchronous machines with bypassed coils using FEM-based modeling software

Abstract

This thesis examines the viability of analyzing large synchronous machine performance with bypassed stator coils using modeling software. Defined operating points of an existing hydro-electric generator with bypassed coils are simulated using Finite Element Method (FEM)-based electromagnetic modeling software using a 2-D model of the generator consisting of the rotor and stator core, rotor poles, field winding, damper bars, and stator coils. Separate electrical circuits for the field winding, the damper winding, and the stator circuits are also defined to simplify the model. The resulting model is then used to simulate a machine at rated operating conditions without bypassed coils and then at various operating conditions with bypassed coils. The results for the model are further analyzed and compared to corresponding measured field data to assess the accuracy of the model.