Turbogenerator end-region magnetic fields

A simple qualitative method of estimating the radial and axial magnetic-field components in the end region of turbogenerators is described. The method, which utilises conducting paper, has been applied to two machines having outputs of 2.5 MW and 500 MW, and has given reasonable agreement with measured results obtained by means of search coils. Although the method is generally used for estimating the axial and radial components of the end-region magnetic field only, sufficient information can be obtained to enable the effect of general design changes to be predicted.