How to arrange subway transformers

With the continuous acceleration of urbanization, urban rail transit system has increasingly become an important means to alleviate urban traffic pressure. As an important part of subway system, power supply system directly affects the safety and stability of subway operation. Among them, as the core equipment of electric energy conversion and distribution, the layout design of subway transformer is particularly important. Reasonable transformer arrangement can not only improve the operation efficiency of power supply system, but also effectively reduce maintenance costs and security risks.

First, the basic function of subway transformer

Metro transformer is mainly responsible for reducing the high-voltage power (such as 110kV or 35kV) transmitted by urban power grid to a voltage level (usually 10kV or lower) suitable for subway traction power supply system, and providing stable power supply for all kinds of equipment in subway stations. According to different functions, subway transformers can be divided into traction transformers and power transformers. Traction transformer is mainly used for traction power supply of trains, while power transformer is used for power supply of auxiliary equipment such as station lighting, ventilation and communication.

Second, the basic principles of transformer layout

In subway engineering design, the layout of transformers should follow the following basic principles:

1. Safety first: Keep away from crowded areas and inflammable and explosive places to ensure the minimum impact on personnel and equipment in case of failure.

2. Easy to maintain: the layout should leave enough maintenance space, and be equipped with necessary passages and fire prevention facilities.

3. Save space: Due to the limited space in the subway station, the transformer layout should be as compact as possible to make full use of underground space.

4. Electromagnetic compatibility: electromagnetic interference with other equipment should be avoided to ensure the normal operation of the communication and control system.

5. Heat dissipation and ventilation: Good ventilation and heat dissipation design is helpful to prolong the service life of equipment and prevent equipment from being overloaded or damaged due to high temperature.

Third, the common layout

According to the specific conditions of subway lines and station layout, the installation methods of transformers mainly include the following:

1. Layout of ground substation: it is suitable for ground station or elevated station, and an independent substation is set near the station, with independent structure and easy management.

2. Layout of underground main substation: it is mostly used in underground rail transit system, usually located in the underground space near the station and connected with traction substation through cables.

3. In-station layout: The transformer is arranged inside the station, which is suitable for stations with tight space, but requires higher fire prevention and safety standards.

4. Layout of mobile transformer: it is used for temporary power supply or emergency power supply for construction, with high flexibility and convenient installation.
　　ourth, the future development trend

With the development of smart grid and digital technology, subway transformers are developing in the direction of intelligence, modularization and energy saving. In the future, subway transformers not only need to have higher energy efficiency ratio, but also need to integrate remote monitoring, automatic alarm and intelligent diagnosis to improve the automation level and operation and maintenance efficiency of subway power supply system.
　　To sum up, the layout design of subway transformer is a key link in the construction of subway power supply system. Only when safety, space, maintenance, ventilation and other factors are fully considered, can an efficient, stable and sustainable subway power supply system be realized and a solid power guarantee be provided for urban traffic.