Oil Preservation System for Transformers

[Engineer1916]

Eng Tips Family,
Can you guys please give me any physical implications of choosing nitrogen blanket vs oil conservator for power transformers? I have a 50MVA transformer and I normally leave upto manufacturer to suggest the oil preservation system. But I am trying to understand the effects of 1 vs the other for example does the main tank size get bigger or smaller for oil conservator or nitrogen blanket etc. I hope I have explained it good enough.

 

[bacon4life]

The overall height including that conservator may taller with a conservator, while the main tank itself may be taller with a nitrogen blanket.

 

[prc]

You have several options- 1) Nitrogen Blanket with automatic gas feeding 2) Conservator with free breathing through silica gel breather (conventional or automatic gel drying type) 3) Conservator with a flexible rubber balloon ( Atmoseal) and silica gel breather connected to pipe from inside of balloon 4) Conservator with a rubber diaphragm floating on the oil with breather over the diaphragm 5) Hermitically sealed unit with flexible tank/radiators to take the oil expansion.6) Conservator with refrigerant type breather. Disadvantage with (1) esp for EHV units is bubble generation during load changes. Today most popular option is (2) &(3)

 

[Bill West]

If your HV is about 138kv or higher the height on the outline drawing is going to be set by the bushings, not the conservator space. Likewise at 50MVA I think the width/length is going to be set by the radiator space and the conservator will just sit above them.

Bill