The design of the gas-filled cabinet provides two options for the protection of the transformer: load switch-fuse combination and circuit breaker with relay protection. As the preferred ring network unit, the gas-filled cabinet can provide a complete set of integrated remote control and monitoring units. The ring network cabinet adopts standardized components such as load switches, SF6 or vacuum circuit breakers, earthing switches, transformers and secondary components. Through the combination of these standardized components, the ring main unit can be widely used in different occasions.
Indoor AC high-voltage gas-insulated metal-enclosed switchgear (hereinafter referred to as "inflatable cabinet") is a new generation of switchgear. The main switch can use either a permanent magnet mechanism vacuum circuit breaker or a spring mechanism vacuum circuit breaker. The whole cabinet adopts air insulation Combined with the SF6 gas compartment, it is both compact and expandable for distribution automation.
The inflatable cabinet has the characteristics of compact structure, flexible operation and reliable interlocking. It can provide satisfactory technical solutions for various applications (especially in harsh environments) and different user requirements. The adoption of sensing technology and the latest protection relays, coupled with advanced technical performance and lightweight and flexible assembly solutions, can fully meet the different needs of users. Inflatable cabinets are suitable for small secondary substations, opening and closing stations, box-type substations, residential quarters, industrial and mining enterprises, large shopping malls in power systems, especially for airports, subways, railways and other occasions with high requirements for electricity.
With the development of the urban power grid and power distribution field, the high cost performance of the ring main unit makes the inflatable cabinet destined to be widely used. Among various types of ring network cabinets, the domestic air-type ring network cabinet has the lowest price, but its performance index is low, the volume is large, and the reliability is not high; the performance index of the vacuum ring network cabinet is higher, but the reliability of the operating mechanism Not high, the technology is not yet mature, and the volume is relatively large; the biggest feature of the fully enclosed combined SF6 ring main unit is that the components in the cabinet are not affected by external environmental conditions such as condensation, pollution, small animals and chemical substances. The best, the highest reliability, the smallest size. In general, SF6 ring main unit is the general trend of ring main unit product development due to its high performance index.From abroad, the development of inflatable cabinets is quite fast, and there are quite a lot of manufacturers. At present, there are mainly Dericher, ABB, Schneider, Siemens, Areva, Ormazabal and other manufacturers, and they are widely used abroad. At present, there are quite a few manufacturers. Many products have entered the country; while my country's inflatable cabinet industry has developed relatively late, the technology is not yet mature, and domestic products are mostly imitation imported products, so imported and joint venture brand products still have considerable technical advantages.
