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What is an oil-immersed transformer?


The low-voltage winding of oil-immersed transformer generally adopts the cylinder structure of copper foil winding, besides the copper conductor with small capacity; the high-voltage winding adopts the multi-layer cylinder structure, which makes the distribution of winding turns balanced, has small magnetic leakage, high mechanical strength and strong short-circuit resistance.


The iron core and winding are tightened separately. The tightening parts of the body height and low voltage lead are all equipped with self-locking anti-loosening nuts. The non-suspension structure is adopted to withstand the shock of transportation.

The coils and cores are dried in vacuum, and the transformer oil is filtered and injected in vacuum to minimize the moisture inside the transformer.

The oil tank adopts corrugated plate, which has breathing function to compensate for the volume change of oil caused by temperature change. Therefore, the product has no oil storage tank, which obviously reduces the height of transformer.

Because the corrugated plate replaces the oil storage tank, the transformer oil is isolated from the outside world, which effectively prevents the entry of oxygen and water and leads to the decline of insulation performance.

According to the above five performances, the oil-immersed transformer does not need to change oil in normal operation, which greatly reduces the maintenance cost of transformer and prolongs the service life of transformer.



Load property

When there are a large number of primary or secondary loads, it is appropriate to install two or more transformers. When one transformer is disconnected, the capacity of the remaining transformers can meet the power consumption of primary and secondary loads. First, the secondary loads should be concentrated as far as possible and should not be too dispersed.

When seasonal load capacity is large, special transformer should be installed. For example, in large civil buildings, the load of air conditioning refrigerators, heating electricity and heat, etc.

When the concentrated load is large, special transformer should be installed. Such as large heating equipment, large X-ray machine, electric arc furnace, etc.

When the lighting load is large or the power and lighting use common transformer seriously affects the lighting quality and lamp life, special lighting transformer can be set up. In general, power and lighting share transformers.


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