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With the improvement of social productivity and people's quality of life, the demand for electricity is continuously increasing. To ensure the effectiveness of power grid system configuration, it is necessary to reasonably construct distribution networks based on actual conditions. However, during the operation of distribution network systems, 17.5kV ring main units play a very important role, so the impact caused by failures is extremely significant. At this point, it is essential to adopt reas

In the rational application of intelligent technologies, the integrated intelligent ring main unit in 10kV distribution automation construction is more conducive to improving the construction level of 10kV distribution automation and ensuring the stability of 10kV distribution automation construction.1 Research Background Integrated intelligent ring main unit.(1) The integrated intelligent ring main unit adopts more advanced technologies, including but not limited to network technology, communic

Eco-friendly gas-insulated ring main units (RMUs) are important power distribution equipment in electrical systems, featuring green, environmentally friendly, and high-reliability characteristics. During operation, arc formation and interruption characteristics significantly affect the safety of eco-friendly gas-insulated RMUs. Therefore, in-depth research on these aspects is of great significance for ensuring the safe and stable operation of power systems. This article aims to investigate the a

From the perspective of insulation performance, sulfur hexafluoride SF6 exhibits excellent insulating properties. Its dielectric strength is approximately 2.5 times that of air, effectively ensuring the insulation performance of electrical equipment under standard atmospheric pressure and ambient temperature. The new SF6 gas free gases used in SF6 gas-free switchgear—such as certain gas mixtures—can also meet insulation requirements, though their specific values vary depending on the formulation

With continuous economic development and the increasing impact of electricity on people's lives, particularly in urban areas with high load density, the reliability of power supply is especially crucial. Establishing a distribution network primarily based on a ring main structure can effectively improve power supply reliability, ensure supply continuity, and minimize the impact of distribution equipment failures and maintenance outages. As a key device in the ring main operation mode, the Ring M

1. Type Test System and StandardsType testing verifies the design rationality and safety of eco-friendly insulated ring main units (RMUs), based on IEC 62271-200 and GB/T 3906, and includes: Insulation Performance: For 12kV RMUs, power frequency withstand voltage is 42kV (1 min) for main circuits and 48kV for breakers. Lightning impulse withstand is 75kV (12kV system) or 125kV (24kV system), with 15 standard impulses (1.2/50μs) per polarity. Partial discharge must be ≤10pC at 1.2&a

1. Gas System FaultsThe most critical type of fault in environmentally friendly gas-insulated ring main units is related to the gas system, primarily involving gas leakage and pressure anomalies. Gas leakage in nitrogen-insulated ring main units mainly stems from seal material aging and welding process defects. Statistics indicate that approximately 65% of gas leakage faults are related to O-ring aging, while 30% are caused by inadequate welding. Gas leakage not only affects insulation performan

1 Characteristics of Nitrogen-Insulated Ring Main UnitsThe new generation of nitrogen-insulated ring main units has the following main characteristics: Excellent insulation performance. All live components are sealed inside, with external surfaces made of insulating material, effectively blocking current flow and preventing interference from external charged objects. Strong resistance to external environmental conditions. Both the enclosure and internal insulation materials possess high resilien

1. Air-insulated and SF₆ Gas-insulated Ring Main UnitsAir-insulated ring main units primarily integrate load break switches, disconnectors, or a combination of both with grounding capabilities, operated either manually or electrically. These units may also incorporate fuses to control cable input and output lines. Conversely, SF₆ gas-insulated ring main units, commonly referred to as gas-insulated switchgear, utilize SF₆ gas for insulation and arc quenching due to its high dielectric strength, p

This paper takes the primary isolation break of a certain type of 12kV air-insulated ring main unit (RMU) as the research object, analyzing the electric field distribution and uniformity around it, evaluating the insulation performance at this location, and reducing discharge risk while enhancing insulation performance through structural optimization, thereby providing a reference for the insulation design of similar products.1 Structure of the Air-Insulated Ring Main UnitThe three-dimensional s