P
Greetings,
I am doing an investigation to an incident within my workplace and unfortunately, some of the questions being raised fall outside my area of expertise.
We have a 132kV feed from the grid which is transformed to 11kv as soon as it comes on site. We have a normal load in the vicinity of 30MW of which approx 20MW is supplied by an onsite Steam Turbine Generator in parallel with the grid.
We recently had a situation where the Steam Turbine did an emergency shut down on a 110% overspeed trip.
The on site DCS, indicates that the main 11kV incomer tripped approx 2 seconds after the overspeed condition occured. This goes against my (somewhat limited) understanding of the principles of parallel operation in that I thought that if the governor failed on the Turbine Generator and tried to overspeed, that it would just take more real load, rather than actually overspeed.
Is it possible that our TG could overspeed whilst still in parallel with the grid, if all indications from the grid show that there was no over frequency condition on the grid.
Any help would be greatly appreciated.
Regards,
Pete.
PS. I hope I've posted this in the correct section.
I am doing an investigation to an incident within my workplace and unfortunately, some of the questions being raised fall outside my area of expertise.
We have a 132kV feed from the grid which is transformed to 11kv as soon as it comes on site. We have a normal load in the vicinity of 30MW of which approx 20MW is supplied by an onsite Steam Turbine Generator in parallel with the grid.
We recently had a situation where the Steam Turbine did an emergency shut down on a 110% overspeed trip.
The on site DCS, indicates that the main 11kV incomer tripped approx 2 seconds after the overspeed condition occured. This goes against my (somewhat limited) understanding of the principles of parallel operation in that I thought that if the governor failed on the Turbine Generator and tried to overspeed, that it would just take more real load, rather than actually overspeed.
Is it possible that our TG could overspeed whilst still in parallel with the grid, if all indications from the grid show that there was no over frequency condition on the grid.
Any help would be greatly appreciated.
Regards,
Pete.
PS. I hope I've posted this in the correct section.