Blackout

First rain sometime makes 500kV transmission isolator goes to conductor due to water contact with dust which lay on. So before rain comes, every isolator should be cleaned from dust, but it is difficult to do cause schedule unit outage is limited for every power station.

Blackout means power station got trip with no electric power supply from outside transmission. So the power station which have hydrogen generator cooled and every rotating equipment must be in concern.


Essential equipment must be running by emergency diesel generator for supply to generator seal oil system, turbine main oil pump and turbine turning device, etc. If emergency diesel generator get fail to start, emergency oil pump for generator seal oil and turbine main oil pump should cut in by DC power and turbine turning should be rotating manually.

As long we were wait for investigation and power supply from outside transmission, operator should be walk down for check every equipment. Submerged scrapper chain conveyor should not fully of slag fell. Keep maintain drum level for get small differential temperature upper and lower not more than 106C. Feed water tank and hot well level also maintain level too. Turbine rupture disk should be not broken by open condenser vacuum break valve and limestone line and tank should be not blocked.

Air heaters should be rotating to avoid deflection due to no uniform of temperature, but they didn’t have power from electric or service air due to compressor got trip too. Leakage control system must be retracted manually due to air heater rotor which got bow from high temperature, so when blackout the temperature was slowly decrease and the rotor bow was slowly back to normal shape. The leakage control systems position before was close to rotor bow, they should be retracted to normal position to prevent the rotor touch with leakage control system plates.

Equipment which supplied from Emergency Diesel Generator
Turbine Area
1. Main Seal Oil Pump 11.0 kW
2. Recirculation Oil Pump 3.7 kW
3. Seal Oil Vacuum Pump 2.2 kW

4. Turning Gear Oil Pump 65.0 kW
5. Turning Devise 45.0 kW
6. Main Oil Tank Extractor 3.7 kW

7. Boiler Feed Water Aux Pump A 11.0 kW
8. Boiler Feed Water Aux Pump A 11.0 kW
9. Boiler Feed Water Aux Pump A 11.0 kW

10. Vacuum Breaker Valve 2.2 kW

12. HP Heater 7 Extraction Valve 2.2 kW
13. HP Heater 6 Extraction Valve 2.2 kW
14. HP Heater 5 Extraction Valve 2.2 kW
15. De-aerator Extraction Valve 2.2 kW
16. LP Heater 3 Extraction Valve 2.2 kW

17. Spare 45.0 kW
18. Spare 11.0 kW
19. Spare 5.0 kW
20. Spare 2.2 kW
Total 195.0 kW

Boiler Area
1. Boiler Elevator 53.3 kW
2. Spare (LCS) 2.2 kW
3. Spare 2.2 kW
4. Spare 2.2 kW
Total 59.9 kW


Normalized
1. Start close cooling pump
2. Start compressor
3. Start circulating water pump
4. start sea water buster pump
5. start air heater
6. start condensate extraction pump