Cooling method of dry-type transformer

Dry-type transformer cooling is divided into two types, one is natural air cooling (AN), the other is forced air cooling (AF).

When air cooled naturally, the transformer can run continuously for a long time under the rated capacity. When forced air cooling, the transformer output capacity can be increased by 50%. Suitable for intermittent overload operation, or emergency overload operation; Due to the large increase in load loss and impedance voltage during overload, it is in a non-economic operation state, so it should not be kept in continuous overload operation for a long time.

Dry-type transformers are widely used in local lighting, high-rise buildings, airports, terminals, CNC machinery and equipment and other places, simply said dry transformers refers to the iron core and winding is not impregnated in insulation oil transformer.

Main forms:

1, open type: is a commonly used form, its body is in direct contact with the atmosphere, suitable for relatively dry and clean indoor, (the ambient temperature of 20 degrees, the relative humidity should not exceed 85%), there are generally air self-cooling and air cooling two kinds of cooling.

2, closed: the device is in a closed shell, and is not in direct contact with the atmosphere (due to poor sealing and heat dissipation conditions, mainly used for mining, explosion-proof type).

3, pouring type: with epoxy resin or other resin pouring as the main insulation, it is simple in structure, small in size, suitable for small capacity transformer.

Features:

1, safe, fireproof, pollution-free, can be directly operated in the load center;

2, the use of domestic advanced technology, high mechanical strength, strong short-circuit resistance, small partial discharge, good thermal stability, high reliability, long service life;

3, low loss, low noise, energy-saving effect is obvious, maintenance-free;

4, good heat dissipation performance, strong load capacity, forced air cooling can improve the capacity of operation;

5, good moisture-proof performance, adapt to high humidity and other harsh environment operation;

6, dry transformer can be equipped with perfect temperature detection and protection system. The intelligent signal temperature control system can automatically detect and display the working temperature of the three-phase winding, automatically start and stop the fan, and have alarm, trip and other functions.

7, small size, light weight, less space, low installation costs.