The efficiency of a power transformer is influenced by a variety of factors, including its design, size, and operating conditions. In general, power transformers are highly efficient, with typical efficiencies exceeding 95%, and often reaching 98% or higher. However, actual efficiency can vary depending on load levels, voltage ratings, and specific design characteristics.Transformer efficiency (η) is defined as the ratio of output power to input power, expressed as a percentage:η = (Outp

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× rat

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 resilience

The switchgear comprises a fixed cabinet and removable components (i.e., the draw-out unit or "handcart"). The cabinet enclosure and partition plates of each functional unit are constructed from aluminum-zinc-coated steel sheets, precision-formed using CNC machinery and assembled with bolts. This ensures dimensional consistency, high mechanical strength, and excellent resistance to corrosion and oxidation. The overall protection level of the switchgear enclosure is IP4X; when the circuit breaker

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