T-MJB102/23 - T-MJB102/23 Flywheel Windings Condition Report
1955
04 - NFTP
BACKGROUND TO THE REQUIREMENT
The JET Flywheel Generator Converters (FGC) are being considered for repurposing following the cessation of JET operations in December 2023. Construction of the FGCs began in 1979 and have been operating since 1983 and so it is important to understand the current condition after 40 years of operations, recommended actions, and to predict future life expectancy.
It is proposed to continue operating the FGCs for another 10-15 years and this work is vital to understanding the operational risks associated.
JET FLYWHEEL GENERATOR CONVERTORS
The FGCs were designed, built, and installed by GEC Large Machines in 1979 as derived from the vertical pump storage hydro-generators used at the Dinorwig pumped storage station. Each FGC is a vertical-shaft oil-bearing machine and is, in essence, two electromechanical machines combined with independent electrical networks. A pony motor sits atop of the flywheel and used to supply kinetic energy over a period, whilst the flywheel rotor and stator windings are used to supply a much larger pulsed power to JET.
THE REQUIREMENT
The JET Flywheel Generator Converters (FGC) are being considered for repurposing following the cessation of JET operations in December 2023. Construction of the FGCs began in 1979 and have been operating since 1983 and so it is important to understand the current condition, any recommended actions, and to predict future life expectancy.
A comprehensive set of inspection and tests is required of the rotating electrical machine windings, i.e., the generator rotor and stator windings, the pony motor rotor and stator windings, to provide that condition analysis.
The last time such tests were performed was 2010 – 2012. Reports on those results exist that can be made available for trend comparisons after contract award.
The supplier is expected to detail what tests and inspections it expects to undertake as part of the response. Rationale for each item is required along with reference to engineering standards and publications where relevant. These inspection and tests may include but are not limited to the following: