12-15-2010, 05:28 PM
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عضو فعال
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تاريخ التسجيل: Aug 2010
الدولة: Egypt
المشاركات: 68
معدل تقييم المستوى: 14
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Over Frquency happened at a windy winter night
at 3:00 am , A sudden frequency fluctuati** happened , that cause the MW output fluctuate with the grid frequency , Unit 7 was at Coordinated Mode ( Boiler Master – Auto , Turbine Set – Auto ) , The load fluctuated accordingly to the frequency from 105 MW to 90 MW, and increased to 105 MW.
After a little time, frequency reached 50.1 HZ – therefore the MW output reached 20 MW,
Also, Boiler Master resp**ds by reducing Air Flow and Fuel Gas Flow for the boiler. The load still decreased until it reached 2 MW, and to (-2 MW), without coming the signal of Reverse Power.
At this instant we trip the turbine manually.
We wanted to c**serve the boiler to be in service, but HP-TBV opens widely ****** 30 sec., and sucking all drum level to +267 mm, resulting MFT Protecti** to the boiler.
The first out indicati** of MFT at BMS was (Drum level HH). “
There were a lot of discussi** and arguments about what is the cause of this accidents , and what should operators do ?
I attached A chart Table shows the different parameters changed at each same time !! , If any **e has an opini** about what happened , plz tell me !!
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