Disclaimer:

Caveat Lector: Although great care has been taken in the compilation of the information contained on this web site, the authors are not liable for the accuracy in terms of error or omission. The information on this web site is subject to change without notice and without obligation on the part of the authors. The authors shall not be liable for technical failures or for failures beyond their control. Some posts may contain authors' personal opinions and views and the authors do not represent any company, corporation or institution.

Thursday, September 23, 2010

Power Transformer Electrical and Mechanical protection

While cleaning some of my old stuff, I found a table about Power Transformer electrical and mechanical protection. This had been used as reference for basic troubleshooting with regards to Power Transformer Protection. This had been my guide when I was still working at Transco. Nevertheless, some of the entries needs to be updated so that it may be applicable to other substations.
Since the table is quite large, I will subdivide it into two parts. So here is the first part of the table:

INDICATORSNATURE OF TROUBLEEFFECTSREMEDIAL MEASURESNOTES
Power Transformer Differental
Operated
Power Transformer Internal Fault
detected
Power Transformer Shutdown/isolation;
actuates lockout relay
Never energize power transformer unless
extensive testing is performed by qualified
peronnel
Lockout Relay cannot be reset unless severe Transformer Fault is not cleared. Breakers are set into lockout operation to prevent energization of Power Transformer
Power Transformer Restricted Earth Fault Potection OperatedExcessive flow of current from high tension windings to groundPower Transformer Shutdown/isolation;
actuates lockout relay
Perform test of Power Transformer as to line-to-ground insulation     -
Power Transformer Overcurrent Protection
i> - Time
i>>- instantaneous
Excessive line overcurrent and/or line to ground faultPower Transformer Shutdown/isolation;
actuates lockout relay
Reset relay and normalize power     -
Power Transformer winding temperature alarmPower Transformer overheating and/or overloadinginsulation deteriorationcheck cooling fan operationVerify corresponding MVA load if within allowable operational limits
Power Transformer winding temperature tripPower Transformer overheating and/or overloadinginsulation deteriorationcheck cooling fan operation. Increase coolingReduce load, implement load curtailment
Power Transformer Oil temperature alarmPower Transformer overheating and/or overloadinginsulation deteriorationcheck cooling fan operation. Verify corresponding MVA load if within allowable operational limits
Power Transformer Oil temperature TripPower Transformer overheating and/or overloadinginsulation deteriorationcheck cooling fan operation. Increase coolingReduce load, implement load curtailment

0 comments:

Post a Comment

Anything in your mind you want to share? Feel free to leave your comments