Conservator tank

 

Conservator tank of Transformer

Details of Conservator tank of Transformer is given below:

1. It is a cylindrical shape Tank which is placed on the top of the transformer.
2. It is connected to main tank of the transformer by short length pipe line.
3. Conservator tank is partly filled with transformer oil.



Fig-1



Fig-2

Now, we describe why the conservator tank fitted to the power transformer?

Conservator is the most vital part of the transformer, because the Conservator tank takes up the expansion & contraction of oil during running operation. When the load of the transformer is increased, the temperature of oil also increases, hence total volume of the oil increases and absorbs the increased volume of oil in upper space of the conservator tank. If the conservator tank is not fitted to the transformer, the transformer will burst out due to high oil pressure at full loading condition of transformer.The outer and inner portion of conservator tank is shown in figure.






Fig-3

Flexible separator or AIR CELL of Conservator Tank

In the large capacity of the power transformer ( above 5 MVA ), a Flexible separator ( Air Cell ) is provided inside the conservator for avoiding direct contact air with the transformer oil.Air Cell provides a permanent, flexible and non-porous barrier between the atmosphere and the transformer oil without affecting the operational function of the system.

The basic construction of the separator is a high resistance fabric coated externally to resist transformer oil and internally to Ozone and weather resistance. The following advantage is given below:-

1. Avoids contact between air and oil.
2. Protection against water vapor and gases.
3. Suppression of any gas bubble formation in oil.
4. Compensation of large volume changes.

Flexible separators are made from coated fabric consisting of :

1. Textile reinforcement i.e highly resistant polyamide fabric.
2. External coating chemically resistance to transformer oils.
3. Inner coating resistance to Ozone and all weather conditions.

Major characteristics of materials are listed below:-
Mass-1400 g/m2
Coating- Poly acrylonitrile butadiene
Textile Reinforcement- Polyamide
Breaking Strength before immersion in oil--> 300 da N/5 cm.