Functional uses of oil-immersed transformer

Functional uses of oil-immersed-transformer


oil-immersed-transformer is a transformer that relies on oil as a cooling medium.

Oil-immersed-transformer generally include two parts, the body and the oil tank, and usually adopt three cooling methods: oil-immersed self-cooling, oil-immersed air-cooled and forced oil circulation.Its models include SVC/TND-5000W (vertical), SVC/TND-7500W (vertical), etc.; product size and weight are 32×28×46 (CM), 36×28×51 ( CM), etc.; the weight is 30/35 (kg), 39/44 (kg), etc. oil-immersed-transformers have the characteristics of strong heat dissipation, low manufacturing and maintenance costs, and convenient recycling. They are suitable for outdoors and places with relatively harsh environments, such as places that need waterproofing, poles, and outdoors.

From the appearance, the packaging forms are different. Dry-type transformers can directly see the iron core and coil, while oil-type transformers can only see the outer shell of the transformer; the lead forms are different. Most dry-type transformers use silicone rubber bushings, while oil-type Most of the type transformers use porcelain bushings

The low-voltage windings of oil-immersed-transformer generally adopt a cylindrical structure with copper foil around the shaft, except for small-capacity copper wires; the high-voltage windings adopt a multi-layer cylindrical structure, so that the ampere-turn distribution of the winding is balanced, and the magnetic flux leakage is small. High mechanical strength and strong short-circuit resistance.

The iron core and the winding are respectively fastened. The fastening parts such as the height of the device and the low-voltage lead wire are equipped with self-locking locknuts. The non-suspending core structure is adopted, which can withstand the vibration of transportation.

Coils and cores are vacuum-dried, and transformer oil is vacuum-filtered and oil-filled to minimize moisture inside the transformer.

The oil tank adopts the corrugated sheet, which has a breathing function to compensate the volume change of the oil caused by the temperature change, so this product does not have an oil conservator, which obviously reduces the height of the transformer.

Since the corrugated sheet replaces the oil conservator, the transformer oil is isolated from the outside world, which effectively prevents the entry of oxygen and water, which leads to a decrease in insulation performance.

According to the performance of the above five points, it is guaranteed that the oil-immersed-transformer does not need to change oil during normal operation, which greatly reduces the maintenance cost of the transformer and prolongs the service life of the transformer.