Coupled Electromagnetic-Fluid-Thermal Analysis for End Zone With Electric Screen in Large Water-Hydrogen-Hydrogen Cooled Turbine Generator Under Different End Winding Extensions

Extension lengths of the stator and rotor end windings will obviously affect the electromagnetic field, fluid flow, and temperature of end components in the end zone of large water-hydrogen-hydrogen cooled turbine generator. In this paper, a 330 MW water-hydrogen-hydrogen cooled turbine generator is analyzed. Flow network of this turbine generator is established. The fluid velocity and the pressure (boundary conditions) are obtained at the different positions of this turbine generator after solving the equations of flow network. Three-dimensional transient electromagnetic field is calculated in the turbine generator end zone. The leakage magnetic field and the losses (heat source) of end components are determined in the turbine generator end zone under the different lengths of stator and rotor end winding extension. Based on these results, three-dimensional fluid-thermal coupled model is given in the end zone. The distribution of complex fluid velocity in the turbine generator end zone is determined. The temperature distribution of the stator end winding, clamp plate, electric screen, and finger plate is studied under the different lengths of stator and rotor end winding extension. The calculated temperature results agree well with the measured values.