Precautions for design of box type substation

The box-type substation can provide "four remote functions", including remote measurement, remote communication, remote control and remote adjustment. Each unit has a separate operation function, and the relay protection function is complete, you can remotely set the operating parameters and control the humidity and temperature of the box to meet unattended requirements. How to better meet actual needs in the design process? Now, the editor of Xianglong Electric will discuss the issues that need attention in the design process.

1. The minimum fire distance between the main transformer and the cabinet should meet the requirements of the "35~110kV Substation Design Code", and the minimum fire distance between a building with a fire resistance class of II and the transformer (oil-immersed) should meet the requirements It is 10m. When the external wall facing electrical equipment (such as transformers, combustible dielectric capacitors, etc.) (which meets firewall requirements) is not provided with doors, windows and openings on both sides of the equipment height range plus 3m and 3m, between the two The fire distance from walls and equipment is not restricted. If there are no general doors and windows, but fire doors are installed within the above range, the fire distance between the wall and the equipment should be equal to or greater than 5m.

The minimum fire resistance rating of the power distribution equipment should be Class II, and the primary system in the power distribution box should adopt a unit vacuum switch cabinet structure. Each unit shall adopt a door structure decorated with specially manufactured aluminum materials, and a double-layer board shall be installed on the back of each bracket, that is, an external door that can be opened. In the design process, the minimum fire distance between the main transformer and the cabinet is 10m to ensure the safe operation of the substation.

2. The exit of the 10kV cable should pass through the steel pipe. In order to make the appearance beautiful, cement pavement should be designed around the box of the substation 10kV box-type distribution station, and the terminal of the 10kV line should be placed 10m away from the substation fence. It is very inconvenient to repair the cables directly buried and led to the terminal. Therefore, the outlet of the 10kV cable should be laid through steel pipes for maintenance and repair by users. If the terminal of the 10kV cable is far away from the substation, the exit between the terminal box of the 10kV cable and the substation fence must pass through the steel pipe. The terminal pole at the end of the cable outlet should be equipped with a new overvoltage protector to prevent overvoltage.