High-voltage ring main units (HV RMUs) are designed to improve power supply reliability, allowing users to obtain power from two directions. They usually connect the power supply network into a ring structure, a power supply mode referred to as "ring network power supply" for short.

In AC 10kV power distribution systems such as industrial and mining enterprises, residential districts, ports, and high-rise buildings, due to the small load capacity, their high-voltage circuits are typically controlled by load switches or vacuum contactors, and equipped with high-voltage fuses for protection.

This system commonly adopts ring network power supply, and the high-voltage switchgear used is customarily called a "ring main unit". In addition to supplying power to the local substation, the high-voltage bus of the HV RMU also needs to carry the through current of the ring power supply network (i.e., the current that supplies power to adjacent substations through the bus of the local substation). Therefore, the cross-sectional area of the high-voltage bus of the HV RMU should be selected based on the sum of the load current of the local substation and the through current of the ring network to ensure that the high-voltage bus does not operate overloaded during operation.

Source: DAYA Electric Group Co., Ltd. Please indicate the source when reprinting: https://www.hygraphics.com/