Monitoring the generator with a fiber-based thermal/strain monitoring system
Derek Hooper walked attendees through the operating principles of a fiberoptic monitoring system for providing online analysis of core temperature and coil motion in electric generators.
The system, which provides a way to assess coil tightness, is a work in progress with early results described by the speaker showing promise.
Sensors, installed before wedging, provide wavelength amplitude measurements which are used to determine the temperature and motion of components. Measurements were taken in several slots during starts and full-load operation at both the turbine and exciter ends of the unit. One of the graphs presented indicated that coil displacement at the end of the core was, perhaps, as much as four times that about 30 in. from the end of the core.