Development of a capacitance measuring robot for the water-cooled stator winding of turbine generators

When water permeates the stator winding insulation in a large-scale turbine-generator, its dielectric strength drops steeply due to wet heat deterioration. A robot, which enables the measurement of water-cooled winding capacitance without removing the rotor, has been developed, confirming good results in the field and contributing to assuring generators with high reliability.