Large Turbine Generator Dynamic Performance Simulation And End Eddy Current Field, The Electric Power Numerical Calculation

The end-winding of a large turbo-generator is consisted of a group of huge current carrying conductors. Due to the strong electromagnetic fields in the end region, these huge current carrying conductors are acted by extremely large electromagnetic forces. Moreover, the electromagnetic forces of the end-winding are synchronously increasing with the increasement in the unit capacity and electromagnetic fields of a large generator. In the normal operating condition, these electromagnetic forces will have a catastrophic effect on the safety operation of the machines since these forces often result in winding vibration and insulator friction, even insulator failure, winding distortion, and fixation break in the extreme condition. Therefore, it is important to study the electromagnetic forces acting on the end winding in order to provide reasonable design guides for engineering applications.This dissertation focuses on the performance simulation, the electromagnetic forces acting on the end windings of a400MW large turbo-generator. The details about the dynamic performance in different operating conditions, the transient eddy current field in the end region and the electromagnetic forces acting on the ending windings of the turbo-generator are reported and some conclusions are given, which may be valuable for engineering applications.1) In order to provide the exciting currents of the eddy current fields and forces acting on the end windings of a large turbo-generator, a circuit model and method based on full variable method for transient performance simulations are devloped.2) The full three dimensional finite element model and method for transient eddy current fields and electromagnetic forces acting on the end windings of large turbo-generators are proposed based on the general electromagnetic theory.3) According to the proposed model and method, a simulation program is developed. Using the finite element analysis software ANSYS and the self-developed computer simulation program, the details about transient performances, the transient eddy current fields in the end region and the electromagnetic forces acting on the ending windings of the400MW large turbo-generator are studied and some valuable conclusions are given.