To enhance power supply stability further, customers can2Power supplies are typically interconnected through a power network, known as ring network power supply. This type of power supply method is commonly used in industrial and mining enterprises, residential communities, seaports, multi-story buildings, and other communication and交流 facilities.10KVIn distribution systems, due to their small load volume, the high-voltage power circuits are typically controlled by load power switches or vacuum contactors, and are equipped with high-voltage fuses for maintenance. The system software is usually powered by a ring main, commonly referred to as a ring main cabinet.
Ring network refers to a circular distribution network, where the power transmission lines form a closed loop. The power supply switches and power sources supply electricity to the circular transmission lines, and then high-voltage circuit breakers distribute power outward from the main lines to the distribution equipment. The characteristic is that each distribution equipment loop can not only obtain power from the switch power source on its left main line but also from the switch power source on its right main line. When an anomaly occurs on the left main line, it will be powered again from the right main line, and when an anomaly occurs on the right main line, it will be powered again from the left main line. Thus, although the total switch power source is supplied unidirectionally, each distribution equipment loop appears to have dual power supply, thereby enhancing the stability of power supply.
The so-called ring main cabinet refers to the fact that each distribution equipment loop is equipped with a switch cabinet.(Team Advances to the Next Round with Out-of-Service Switchgear)The busbar channel of this switchgear is also a part of the ring main. In other words, the ring main is formed by connecting the busbars of each outgoing cabinet. Each outgoing cabinet is called a ring main cabinet. In fact, it's not possible to see the significance of the ring main by extracting a single ring main cabinet independently.
The rated voltage of this ring main cabinet is not high, so the high-voltage circuit breakers in the ring main cabinet generally do not use complex disconnect switches, but instead opt for simple fuse high-voltage load switches. In other words, the high-voltage circuit breakers in the ring main cabinet are typically load switches. The load switches in the ring main cabinet handle normal electrical currents, while the circuit breakers disconnect short-circuit capacities; together, they replace the disconnect switches. Naturally, this is limited to a certain volume.
These switch cabinets can also be used in distribution systems not constructed with ring network configurations. Therefore, with the widespread application of these switch cabinets, the ring main cabinet has emerged outside the scope of ring main distribution equipment, generally referring to high-voltage switch cabinets with load switches as the main power switches.
The ring main cabinet incident occurred over a brief period, but has gained widespread application in recent years, primarily due to the newly developed and designed industrial production facilities and institutional buildings. From the perspective of the power supply and distribution system, the majority of small and medium-sized transformers have a capacity that generally does not exceed...1250KVAOur power supply has been stable and long-lasting, with infrequent operations of high-voltage circuit breakers. For such clients, although the ring main unit is not perfect, it is more than sufficient. With the development of large and medium-sized urban planning and construction, many multi-story buildings have emerged, and substation stations are usually located underground. According to fire safety regulations, the equipment in substation stations must be oil-free. To optimize the use of working area, the equipment should be miniaturized, thus ring main units, high-voltage circuit breakers, oil-immersed transformers, and dry-type voltage transformers are brought into the buildings. The ring main unit has a simple structure, reliable operation, and low maintenance, resulting in low operation costs. Compared to switchgear with isolating switches, it offers distinct advantages. The ring main unit requires higher load switch characteristics and a smaller volume, leading to the emergence of new load switches.
