The generator has been detached and the turbine cannot spin at 3000 rpm for a long time.
Generator decoupling means that the main steam valve is closed, the excitation switch is tripped, and the output circuit breaker is tripped. There is neither original power nor power from the electrical network, so it is impossible to maintain it. 3,000 rpm.
Looking at the problem of 3000 rpm steam turbine alone: when the main steam valve is closed by mistake or the furnace protection action closes the main steam valve but If the generator output switch does not trip, the generator switches to the engine running state. At this time, the generator absorbs active and reactive power from the system, this operating condition has no impact on the generator. However, due to loss of wind, the rear turbine blades may overheatr. , damaging the tail blades and causing turbine accidents. Therefore, large units are not allowed to operate for a long time under these working conditions and are only allowed to operate for a few minutes at most. At this time, the reverse power protection of the generator-transformer group will operate at a complete stop.