The power transformer is the power plant and substation is one of the main equipments. The role of the transformer is in many ways not only can increase the voltage of electric energy to electricity, but also reduce the voltage to the voltage levels in use, in order to meet the demand for electricity. In short, boost and buck must be completed by the transformer. In the process of the transfer of power in the power system, will produce voltage and power loss in the two part, conveying the same power when the voltage loss is inversely proportional to voltage, power loss and voltage is proportional to the square of the. Use transformer to improve the voltage, reduce the loss.
The transformer is composed of a wound on the same core of two or more than two of the coil winding, winding through the contact between the alternating magnetic field and according to the working principle of electromagnetic induction. Transformer installation position should be considered for operation, maintenance and transportation, and should choose a safe place. The rated capacity in the use of transformer transformer should be chosen reasonably. The transformer no-load reactive power, need large. The reactive power to the power supply system of supply. Transformer capacity if selection is too large, not only an increase of the initial investment, but also the transformer for a long time in no-load or light load operation, so as to increase the proportion of no-load loss, lower power factor, increase the network loss, this operation is not the economy and unreasonable. The choice of transformer capacity is too small, can make the transformer overload long, easy to damage the equipment. Therefore, the rated capacity of the transformer should be selected according to the needs of the electrical load, should not be too large or too small.