Dynamic Deformation and Strength of Stator end Windings During Sudden Short Circuits

A strain measurement technique was developed in order to reduce the disturbance caused by the electromagnetic field. Using this technique, a series of short circuit tests were carried out on a 21000 kVA two-pole turbine generator. The strain and displacement induced on the stator end windings were measured under various short circuit voltages. The mechanical strength of stator windings against a sudden short circuit is discussed in relation to the variations in tan6 and breakdown voltage characteristics, and is also discussed in comparison with the measured strains induced on the stator end windings and the ultimate strains obtained by the tensile and bending tests on test bars.