Overload Analysis of Power Transformer

Overload normal load and accident over load two cases. Normal overload is in the normal power supply, the user caused by increased power consumption. It will cause the oil immersed distribution transformer temperature rise, causes the transformer insulation to accelerate the aging, the service life reduces, therefore, under normal circumstances does not allow the overload operation. Special circumstances Transformer can be overloaded in a short time, but in winter shall not exceed the rated load of 30% in summer shall not exceed 15% of rated load. In addition, the transformer should be based on the temperature rise and the provisions of the manufacturer to determine the overload capacity of the transformer. When the power system or the user substation accident, in order to ensure the continuous supply of important equipment, it allows the transformer short-term overload operation, that is, accident overload, accident overload will cause the coil temperature exceeds the allowable value, so the insulation in terms of Faster than normal aging conditions. But less chance of accident overload, under normal circumstances the Amorphous Core Transformer is under-load operation, so short-term overload caused by damage to the transformer insulation. The time and the multiples of the accident overload shall be carried out in accordance with the provisions of the manufacturer.