Refurbishing and Rewinding Motors/Generators – Critical Steps that Ensure Long-Term Reliability
Refurbishment of hydro motors/generators includes replacement of stator windings and laminations and re-insulation of field pole windings. Typically hydro refurbishment occurs about every 35 years (stator windings) and every 70 years (stator windings, stator laminations and field pole windings). This session will highlight and detail the critical steps to the rewind process (teardown attributes and what to look for, the step-by-step critical rewind installation process, inspection criteria during manufacturing of new stator windings, new stator laminations, and re-insulation of rotor field pole windings), testing requirements during and at the completion of the rewind, and performance test criteria after the rewind during initial start-up. Collectively, the teardown phase, installation phase, manufacturing phase, testing phases, and final performance testing ensure long-term reliability from an asset management perspective. Warranty inspections at 1, 3 and 5 years will also be discussed.