Gas generator stator rewinds
GE Vernova offers a portfolio of stator rewind solutions engineered to help extend asset life, improve availability, and manage outage duration across a wide range of legacy GE Vernova generators.
Benefits
Extend generator stator life and boost output
Gas turbine generators face intense thermal demands and frequent cycling that can degrade insulation, create hot spots, and accelerate component wear, increasing the likelihood of unplanned outages. Stator rewinding is a proven solution to counter these effects. GE Vernova’s stator rewinds and upgrades incorporate advanced insulation systems, improved end‑winding support, and validated manufacturing processes to extend stator life, enhance reliability, and increase output while preserving long‑term asset value.
Benefits of GE Vernova's stator solutions:
Core offering
Conventional stator rewind
Our approach starts with a core, conventional stator rewind offering as the base scope for most legacy GE Vernova generators. It is a configurable, field-proven solution that restores the stator winding system and associated components to support long-term reliability.
While the exact scope is tailored to each unit, a typical conventional rewind service includes:
NEW STATOR BARS AND INSULATION
- Removal of existing top and bottom bars.
- Configuration, manufacture, and installation of new bars using GE Vernova insulation systems.
- Re-establishment of end-winding geometry and electrical clearances.
SLOT AND END-WINDING SUPPORT SYSTEM
- Renewal or adjustment of slot wedging to restore mechanical support and contact.
- Inspection and reuse or upgrade of end-winding supports/binding bands, as appropriate.
- New end-winding lacing and ties to help stabilize the end regions.
CORE AND INSTRUMENTATION
- Inspection of the magnetic core to identify hotspots, looseness, or damage.
- Core repairs or restack where required or selected.
- Review and potential upgrade of thermal instrumentation to support modern monitoring strategies.
CONNECTIONS AND TERMINALS
- Rework of series and phase connections to meet electrical and mechanical engineering criteria.
- Inspection and cleaning of phase rings and bushings.
- New connection rings frequently quoted as an option and added where condition, risk profile, or customer strategy warrants.
ONSITE SERVICES AND TESTING
- Controlled disassembly and access to the stator.
- Onsite stator unwinding and rewind activities.
- Cleaning, coating, and standard electrical tests (e.g., high-voltage tests) before returning the unit to service.
Flex Pack
Optional enhancement: GE Vernova's Flex Pack
As an optional enhancement to a conventional stator rewind, GE Vernova’s Flex Pack is configured to support today’s increasingly cyclic operating profiles by reducing thermal and mechanical stresses in the stator end‑winding system. It helps lower the risk of forced outages and premature rewinds by supporting critical components to accommodate axial movement during operation.
Flexibility and durability
The Flex Pack enhances flexibility and durability through:
- Two-piece sliding axial supports that replace fixed supports, helping to enable uniform thermal growth of the endwinding support system.
- Flexible lead connections between the connection rings and highvoltage bushings, supporting axial movement without transferring stress to the bushings (standard on steam turbinedriven H33 and H53 generators).
By supporting controlled movement rather than constraint, the Flex Package improves stator resilience and reliability under cyclic duty.
Benefits
A longer stator lifetime that works well for modern operating conditions.
Up to 5,000 start-stop cycles with legacy copper.
Up to 10,000 cycles with advanced copper.
Additional offerings
Generator stator alternative use cases
GE Vernova offers additional solutions for scenarios where traditional rewinds may not be appropriate. Whether you opt for fast stator rewinds or replacement stator, these flexible pathways maintain our advantage of standardization, quality, and reliability while supporting operators to match solutions to their specific needs.
- Fast stator rewind
- Replacement generator stator
Fast stator rewind (FSR) is GE Vernova’s standardized stator rewind solution for indirectly cooled generators up to 300 Megavolt-ampere (MVA). It replaces one-off rewinds with a repeatable “one technology, one process” approach, cutting typical on-site rewind activities from as long as 120 days down to about 35 days on average.
Benefits include:
- Extended asset life with modern insulation (such as MICAREX) and renewed slot/end-winding support.
- Improved availability and reliability by correcting known defects and aligning to current operating modes.
- Controlled outage durations, from planned conventional rewinds to fast stator rewinds in as few as 16–59 days.
- Better assured quality and EHS performance via standardized processes, tooling, ITPs, cold‑cure resin, and induction brazing.
- Applied tech primary rewind package for units like 23z-109, 18L, 21Z (the technology is also used with legacy GEV units like the model 324, 7A6).
When outage windows are too tight for a conventional rewind, or a rewind is not recommended due to the particularities of a unit's engineering, another effective solution is to replace the entire stator assembly. With GE Vernova, replacement stators can be manufactured in parallel with ongoing plant operations, which supports undisrupted generation and reduced downtime.
Benefits include:
- Proven stator configurations engineered for more dependable performance, using GE Vernova’s established technologies and processes to help support long‑term reliability.
- Replacement stators that modify obsolete systems with modern technology, providing a practical way to upgrade aging large stators built through older methods.
- Emergency response and strategic spare options engineered to improve unit availability, such as complete spare stators that support outage planning and help restore service rapidly in unplanned situations.
