Power transformer action

   Power transformer is one of the main equipments in power plant and substation. Transformer's function is various not only can raise the voltage to send the electric energy to the electric power area, but also can reduce the voltage to each level using the electric voltage, meets the electric power demand. In short, the step-up and step-down must be carried out by the transformer. In the process of power transmission, voltage and power must be lost. The voltage loss is inversely proportional to the voltage and the power loss is inversely proportional to the square of voltage. The use of transformers to increase the voltage and reduce the power transmission losses. The transformer is composed of two or more windings wound on the same iron core. The windings are connected by alternating magnetic field and work according to the principle of electromagnetic induction. Transformer installation location should be considered for easy operation, maintenance and transportation, and should choose a safe and reliable place. The rated capacity of transformer must be selected reasonably when using transformer. Large reactive power is needed in no-load operation of transformer. The reactive power is supplied by the power supply system. If the capacity of the transformer is too large, not only the initial investment is increased, but also the transformer is operated in no-load or light-load for a long time, which makes the proportion of no-load loss increase, the power factor decrease and the network loss increase, it's not economical or rational to operate like this. The transformer capacity choice is too small, will cause the transformer long-term overload, easy to damage the equipment. Therefore, the rated capacity of transformers should be based on the need for power load selection, should not be too large or too small.