SF6 ring main unit shall be processed according to the drawings

1 SF6Overview of ring main unit

It is the model XGN15-12Because it adopts a ring network distribution system, it becomes a high-voltage ring network cabinet. The ring network distribution system refers to a high-voltage switchgear that adopts a dual inlet mode, with one inlet cabinet installed at each end, forming a closed power supply system to ensure the stability of power supply. SF6 high voltage ring main unit is a high voltage ring main unit with SF6 load switch as the main switch.

SF6 ring main unit is a medium voltage electrical combination equipment with load switch as the core component, which can be freely combined into multiple circuits with switching, connection, and protection functions for the power system. Its main circuit core components are composed of SF6 load switches or additional circuit breakers and other primary auxiliary electrical appliances.

2、 Ring main unit structure

SF6 ring main unit is divided into three main parts: control room, busbar room, and cable room.

1. The control room is mainly equipped with operating mechanisms and secondary line circuit control switches. It is the control center of SF6 load switchgear. Through the control room, the switch opening and closing, grounding knife opening and closing, and secondary circuit on and off can be controlled.

2. The busbar room is relatively simple, with SF6 load switches installed. The busbar is connected to various high-voltage switchgear through the busbar room.

3. The cable room is the largest compartment in terms of space, mainly used for connecting external cables, and also has sufficient space to install grounding switches, lightning arresters, heating plates, lighting fixtures, current transformers, etc.

3、 Principle of High Voltage Ring Main Unit

The circular power supply of the entire high-voltage power supply system is implemented using dual incoming lines. When one circuit fails, there is another circuit that can provide power.

The performance of SF6 high-voltage ring main unit is mainly determined by SF6 load switch. SF6 gas has good insulation and arc extinguishing performance. Installing the switch in fully enclosed SF6 gas can effectively improve the stability and service life of the switch. Therefore, the service life of SF6 high-voltage ring main unit is up to 20 years.

SF6 ring main unit shall be processed according to the drawings

In recent years, SF6 ring main unit has developed rapidly, and its manufacturing process and product reliability are on par with international electrical appliances. However, there is still a certain gap compared to foreign manufacturers in voltage levels between 24kV and 40.5. At present, domestic manufacturers produce SF6 power distribution grade for 40.5kV level. The rest are C-GIS systems based on high current and large capacity primary power systems.