Analysis of magnetic forces and vibration in a converter-fed synchronous hydrogenerator

Abstract

This paper investigates the influence of converter-fed operation on magnetic forces and radial vibration in a hydrogenerator. Flux density distribution is computed using time-stepping finite element (FE) analysis and used to calculate force density distribution based on Maxwell stress tensor. Both temporal and spatial characteristics of selected flux density and force density waves are studied. Important spatial harmonics of radial forces are investigated and compared for converter-fed and converter-less operations. Vibration analysis is also presented based on the magnetic field data computed by FE analysis.