Rotor-mounted scanning of stators in hydro and turbine-drive generators

Abstract

Comprehensive rotor-mounted scanning of hydrogenerator stators has attained commercial status on the basis of prototype development and extensive beta-site testing on four generators and two pumped-storage units ranging in capacity from 22 to 450 MVA. Thermal, RFI, acoustic, air-gap, magnetic, and rotor vibration sensors are monitored in real-time to provide early warning of impending failures. Resulting data are continuously processed for alarm conditions, analyzed for anomalous technology, and archived for future trend assessment. This technology is now being extended to two and four-pole turbine-driven generators in which the environment is far more severe than in salient-pole hydro machines. The authors provide graphic results obtained using hydrogenerator scanners and describe techniques under development to achieve comparable results with turbogenerator scanners.