How to boost the transformer in power plant

In modern power system, the efficient transmission of electric energy is an important foundation to ensure the normal operation of social production and people's lives. As the source of power system, the power generated by power plant often needs long-distance transmission to reach the user. In order to reduce the loss of electric energy in the transmission process and improve the transmission efficiency, power plants usually use transformers to raise the voltage, that is, "boost". This paper will briefly introduce how the transformer in power plant is boosted.

First, why do you need to boost the pressure?

The voltage generated by generators in power plants is generally 6kV, 10kV or 35kV, while long-distance transmission requires higher voltage, such as 110kV, 220kV or even more than 500kV. According to the electrical formula $ P = UI $ (power = voltage× current), under the condition of constant transmission power, increasing voltage can significantly reduce current. The reduction of current can effectively reduce the resistance loss on the transmission line ($ P_{ loss} = I^2 R $), thus improving the transmission efficiency and reducing energy consumption.

Second, the basic principle of transformer

Transformer is a device that works by electromagnetic induction principle. It consists of iron core and windings, which are divided into primary winding (primary winding) and secondary winding (secondary winding). When alternating current passes through the primary winding, it will generate an alternating magnetic field in the iron core, and then induce voltage in the secondary winding. By changing the turns ratio of the primary winding to the secondary winding, the voltage can be increased or decreased.

The step-up transformer is characterized in that the number of turns of the secondary winding is more than that of the primary winding. For example, if the primary winding is 100 turns, the secondary winding is 1000 turns, and the turn ratio is 1:10, then the output can reach 100kV by inputting 10kV voltage.

Third, the application of step-up transformer in power plant

In a power plant, the step-up transformer is usually the key equipment to connect the generator with the transmission network. Its workflow is as follows:

1. Generator output: The power generated by the generator is usually about 10kV.
2. Step-up transformer works: the electric energy enters the primary side of the step-up transformer, and the transformer raises the voltage to 110kV or higher to meet the demand of long-distance transmission.
3. Access to the power transmission system: the boosted high-voltage electricity is sent to the substation through the power transmission line, and then distributed to users after the step-down treatment.

In addition, large power plants may use a variety of transformer combinations such as "main transformer" and "tie transformer" to realize flexible conversion between different voltage levels and power dispatching.

Fourth, summary

Step-up transformer is an indispensable and important equipment in power plant, which realizes the voltage increase through electromagnetic induction principle and effectively solves the energy loss problem in long-distance transmission. With the development of smart grid and new energy generation, the future step-up transformer will be upgraded in the direction of high efficiency, energy saving and intelligence, which will provide strong support for building a green, safe and efficient power system.