Electromagnetic (EM) analysis of hydropower generators iscommon practice but there is little emphasis on studying the effect of rotorwhirling in the analysis. This paper explores the effect on electromagneticanalysis as the rotor is allowed to whirl both in forward and inbackward directions under no-load conditions. As a hydropower generatorrotor shaft can experience whirling when under eccentric operation,the objective is to examine how whirling can affect the unbalancedmagnetic pull (UMP), flux densities, damper currents, and ohmic lossesin a synchronous hydropower generator. These results are obtained ina commercial FEM-based EM field modelling software package thatallows various degrees of freedom in motion types and multiple motioncomponents to be set. It is seen that backward whirling tends to inducehigher eddy currents than forward whirling does.
Godkänd; 2016; 20150702 (andbra)