The power transformer is the main equipment in power plants and substations. The role of the transformer is multi-faceted. It can not only increase the voltage to send electric energy to the area where electricity is used but also reduce the voltage to the voltage used at various levels to meet the electricity needs. In short, both step-up and step-down must be done by transformers.
In transmitting electric energy in the power system, there will inevitably be losses in voltage and power. When transmitting the same power, the voltage loss is inversely proportional to the voltage, and the power loss is inversely proportional to the voltage square. Transformers are used to increase voltage and reduce power transmission losses.
A transformer is composed of two or more coil windings wound on the same iron core. The windings are connected through an alternating magnetic field and work according to the principle of electromagnetic induction. The installation location of the transformer should be convenient for operation, maintenance, and transportation, and a safe and reliable place should be selected.
When using a transformer, the rated capacity of the transformer must be selected reasonably. When the transformer is running without load, it needs a large amount of reactive power, which the power supply system must supply.
Suppose the capacity of the transformer is too large. In that case, it will not only increase the initial investment, but also make the transformer run at no-load or light load for a long time, which will increase the proportion of no-load loss, reduce the power factor, and increase the network loss. Such an operation is neither economical nor unsafe. Reasonable.
If the transformer capacity is too small, the transformer will be overloaded for a long time and the equipment will be easily damaged. Therefore, the rated capacity of the transformer should be selected according to the needs of the electrical load and should not be too large or too small.