Why cooling is necessary in a transformer?
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Why cooling is necessary in a transformer?
Cooling of a transformer is the process of dissipation of heat developed in the transformer to the surroundings. The losses occurring in the transformer are converted into heat which increases the temperature of the windings and the core. In order to dissipate the heat generated cooling should be done.
Where are oil cooled transformers used?
outdoor installations
Oil cooled transformers are used in outdoor installations due to the possibility of oil leakage and spills which pose a fire risk, but these units are more environmentally friendly.
Which type of cooling is employed for distribution transformer of 200 KVA?
200kVA 3-Phase Oil Cooled Distribution Transformer
| Power Rating | 200kVA |
|---|---|
| Voltage Ratio | 11kV/433V |
| Cooling Type | Oil Cooled |
| Winding Material | Copper |
| Brand | MEI |
What are the standard sizes of transformers?
Especially for commercial buildings, the most common sizes for transformers are the following:
- 3 kVA.
- 6 kVA.
- 9 kVA.
- 15 kVA.
- 30 kVA.
- 37.5 kVA.
- 45 kVA.
- 75 kVA.
How do you determine the power rating of a transformer?
Use the formula: P(KVA) = (V^2/R)/1000 where R is resistance in ohms. For example, if V is 120 volts and R is 50 ohms, P(KVA) = V^2/R/1000 = (14400/50)/1000 = 288/1000 = 0.288 KVA. Calculate power rating in KVA when you know power in watts and the power factor.
How is a power transformer cooled?
By Air Natural method the generated heat in the transformer is cooled by the circulation of natural air. When the temperature of the transformer becomes higher as compared to the temperature of the surrounding air, thus by the process of natural convection, heated air is replaced by the cool air.
What is oil cooled transformer?
2. Oil cooling (Oil immersed transformers) In this method, heat is transferred to the oil surrounding the core and windings and it is conducted to the walls of the transformer tank. Finally, the heat is transferred to the surrounding air by radiation and convection.
Which is the common method of cooling a power transformer?
Oil cooling
The losses occurring in the transformer are converted into heat which increases the temperature of the windings and the core. In order to dissipate the heat generated cooling should be done. Oil cooling is the commonly used method for cooling purpose.
How are transformers generally cooled for installations rated at less than 5 KVA?
Oil acts as a best coolant material, for transformer cooling. Due to its high efficiency as a coolant it is most widely used in transformers. Not only same but Oil with suitable properties can be used for various power transformers according to their ratings.
What does 1500 kVA rating on a transformer mean?
The unit kVA means kilovolts-amperes which represents the apparent power of the transformer. Thus, the rating 1500 kVA implies that this transformer can hold any apparent power below 1500 kVA. However, thresholds to consider in the electrical industry may affect the transformer’s power holding capacity.
How many volts does a 75 kVA transformer produce?
If your transformer has a kVA rating of 75 and your amperage is 312.5, you’ll plug those numbers into the equation — 75 * 1,000 / 312.5 = 240 volts. The primary and secondary circuits coil around the magnetic part of the transformer.
What are the different types of liquid transformer cooling?
Below, we look at some examples of modern liquid transformer cooling classes along with their designations prior to ANSI/IEEE C57.12.00-2000: Oil-immersed, self-cooled. Transformer windings and core are immersed in some type of oil and are self-cooled by natural circulation of air around the outside enclosure.
What is the cooling rating of transformer coil?
Transformer coil and core are immersed in oil. This transformer has two ratings. Cooling for one rating (OW) is obtained as previously described. The self cooled rating (A) is obtained by Natural Circulation of air over the tank and cooling surfaces.