Industrial and mining enterprises as well as civil buildings use oil-immersed transformers to convert network voltages of 10(6)kV or 35kV to busbar voltages of 230/400V. Suitable for AC 50/60Hz, three-phase maximum rated capacity of 2500kVA, can be used indoors, and can be installed on a pole when the capacity is 315kVA and below, and the ambient temperature is not higher than 40°C, not lower than -25°C, the relative humidity is not greater than 90% (ambient temperature is 25°C), and the altitude is not higher than 1000m.
Performance Characteristics Of Oil Infiltration Transformers
- Low-voltage windings of oil-immersed transformers use copper conductors during small magnetizations, and high-voltage windings have multilayer cylindrical structures. The winding ampere-turn distribution is balanced, magnetic leakage is small, mechanical strength is high, and short-circuit resistance is high.
- The fastening parts such as the height of the device and the low-voltage lead wires are equipped with self-locking lock nuts, and the non-suspended structure can withstand transportation shocks.
- The coil and iron core are vacuum dried. Vaccum oil filtration and filling are used in oil-type transformers to minimize moisture accumulation.
- The oil tank uses a corrugated plate, which has a breathing function to compensate for volume changes caused by temperature changes, thereby eliminating the need for an oil conservator, which reduces the transformer’s height.
- With the corrugated plate replacing the oil conservator, the transformer oil is isolated from the outside environment. Consequently, oxygen and water are prevented from entering and insulation performance is reduced.
- Oil-immersed transformers have a heat resistance of Class A, and their long-term operating temperature is 105°C. Low viscosity, good heat transfer performance, and reduced aging of insulating materials make it excellent for extending transformer life.
Advantage of Oil Infiltration Transformers
- It has good insulation properties, good thermal conductivity, and is inexpensive.
- Infiltration transformers provide high voltage insulation while dissipating large amounts of heat.
Disadvantage of Oil Infiltration Transformers
- An oil-immersed transformer’s oil is flammable and may burn and explode if it encounters a flame, which is extremely hazardous.
- It is harmful to the human body to be immersed in oil
- To avoid safety accidents, oil-immersed transformer oil should be regularly checked
- Oil-immersed transformers have poor sealing performance and should be aged, and oil leaks are a serious concern on the operating site, affecting the safe operation of equipment and polluting the environment
- Oil-immersed transformers have low insulation levels, and they only need to be designed and manufactured according to A-class insulation, and their insulation effect is the lowest
