Cooling Features Of Dry-Type Transformers

Dry-type transformers are one of the important power equipments in distribution lines. They have the advantages of high dielectric strength, strong short-circuit resistance, environmental protection, fire protection, explosion-proof, maintenance-free and other advantages, which are increasingly favored by users. Therefore, for the installation technicians, it is necessary to use professional and scientific technology to make various preparations, solve and summarize the problems in the installation process in time, and ensure the safe operation of the equipment.

Cooling method for cooling dry-type transformers. The cooling methods of dry-type transformers are divided into natural air cooling and forced air cooling. When the natural wind is very cold, the rated capacity of the transformer can run continuously for a long time. Forced air cooling increases the output capacity of the transformer by 50%. Suitable for intermittent overload operation or emergency overload operation. During overload, load losses and impedance voltages increase significantly, and non-economical operation occurs. Continuous operation for a long time is not desirable.

Dry-type transformers have strong moisture-proof properties, but due to the openness of their structure, especially dry-type transformers produced in China have low insulation levels (low insulation levels), they are susceptible to moisture. Therefore, dry-type transformers can work at 70% relative humidity and can achieve high reliability. Dry-type transformers should also be avoided for extended periods of time and to avoid severe exposure to moisture. When the insulation resistance is lower than 1000/V, it indicates that there is serious moisture in the transformer, and the trial operation stops.