Resolve corona discharges in the generator stator windings

摘要

With the quick development of the power grid in Guangdong Province, pumped storage power stations have been developing in large capacity form of grid energy storage in Guangdong Power Grid, for meeting the industrial load demand. The pumped storage power stations act as peaking plants and provide emergency response to sustain safe and reliable power supply in the network systems. Pumps and generators are core equipment in pumped storage power stations, while stator windings are core components of pumps and generators as they play vital roles in mechanical and electrical energy conversion processes. In October 2014, during second 10-Year overhaul to Pumped Storage Unit 1 of Phase One Guangzhou Pumped Storage Power Station (GPSPS), corona discharges were observed near the outlet of the stator windings slots, on end-regions, and both the top and bottom stator windings. That would be shortening lifespan of the windings' insulation, if it were not treated properly and the discharge might also endanger station operational staff.