Switchyard Improvements and Protection Levels

Consult an appropriately-qualified HV designer locally. It would be most unwise to rely on answers to this topic from anonymous respondents to an international engineering discussion topic forum!

DEFINITELY, YOU NEED A CONSULTANT OF HIGH EXPERIENCE CALIBER. BUT TO HAVE AN IDEA OF THE SCOPE OF ACTIONS TO BE TAKEN,

1. CT s ratio be checked. CT primary rating should match with the max. line current at 1400 MW load. Protection windings CT ratio may be 2* Ir or as suggested by your design consultant.

2. PTs shall not be replaced. As the voltage levels are not changed.

3. As the fault levels at 1400 MW are different, Relay settings of over load / earth fault / differential protection / etc.. shall change.

4. Protection levels in general will be same as that of for 1050 MW. But you may think of Multi function protection relays / microprocessor based relays / PC commumicable relays /On line monitoring instruments etc.. for more reliability & accuracy.

If the plant was running at 1050MW and is now running at 1440MW and you didn't make the necessary changes for the massive load increase (or include them in the original design), then immediately shut the switchyard down before something overheats and blows up (which it will). Get a professional in to check and alter the design accordingly, while firing the appropriate management and/or design/commissioning engineers for gross negligence.

This reminds me of the navy sailor who found a bomb on a ship (details withheld for security reasons) and walked around with it until he could find his superior officer to ask him what to do with it. Where is the common sense?

1ST of all

agree with the experts need consultant ...

however ,

1--- 1050MW ---1400MW -- calculate S , P , Q

2 --- available short ckt at each level

3---- breaker settings

4----relay setting better to use sw for cordination curves

5----prepare good excel sheets for faster calculations

6----BIL insulations level

7----earthing

would be more happy if some one add more

good luck