Underground Transformer
Underground transformers are generally installed in manholes and small pits in underground trenches. For its special operating environment, sealing, waterproofing, insulation, corrosion and rust prevention, and temperature rise control are key components of product design. The performance of the designed product is generally required to meet the most advanced level of domestic distribution transformers.
In situations with large load changes, on load capacity and voltage regulating transformers can be used underground, which will be more energy-efficient.
Scope of application:
Lighting systems for central urban areas, streets, highways, bridges, tunnels, parking lots, airports, ports, tourist attractions, etc.
Performance characteristics:
Technical parameters:
Maximum ambient temperature:+ 55℃；
Minimum ambient temperature:- 10℃；
Highest monthly average temperature:+ 45 ℃.
No explosive or corrosive gases, no severe vibration or impact at the installation location, the transformer can operate for a long time in a pit or soil, and the oil tank and exposed parts can be submerged in water.
Product technical indicators: mainly based on national energy-saving product indicators.
Voltage level: High voltage: 6kV, 10kV;
Low voltage: 0.4kV;
Rated frequency: 50Hz;
Rated capacity: 30kVA~1600kVA.
① Good sealing performance to meet the requirements of product operation. Product immersion test is required. The water surface should be at least 200mm above the highest point of the product, and the duration should not be less than 24 hours. After that, insulation resistance measurement should be carried out underwater, and external withstand voltage and induction withstand voltage tests should be conducted in accordance with the provisions of JB/T501.
② The operating environment temperature of underground transformers is generally allowed to be 10 ℃ higher than the normal environment temperature, so the temperature rise limit of each part of underground transformers is generally required to be 10K lower than the corresponding national standard specified value of conventional products, that is, the temperature rise of the top oil layer is controlled at 50K, and the temperature rise of the winding is controlled at 55K.
③ The exterior of the underground transformer oil tank or box and all exposed metal parts should be coated with anti-corrosion materials or made of anti-corrosion materials due to long-term exposure to harsh environments, and the surface should be smooth and even.
④ There should be mechanical strength requirements for underground transformer oil tanks, which should be undamaged and free from unacceptable permanent deformation under a positive pressure of 50kPa; No cracking shall occur under a positive pressure of 100kPa.
⑤ The pit for installing underground transformers can have appropriate space around it according to the rated capacity, drainage facilities, ventilation and manholes on the pit cover for heat dissipation and observation of operation.
Execution standards:
GB 1094 Power Transformers
GB/T 6451 Technical Parameters and Requirements for Oil immersed Power Transformers
GB/T 10228 Technical Parameters and Requirements for Power Transformers
IEC 60076 Power Transformers
IEC 60354 Load Guide for Transformers
Our technological advantages:
Integrating electromagnetic optimization design, parametric drawing, performance analysis and structural optimization, automatic drawing, and other functions of transformers to achieve resource sharing in transformer design, as well as searching, modifying, and version control of various data information.
The current field, temperature field, electric field, leakage magnetic field, wave process, and short-circuit force of transformers. The research and design of each series of products are carried out through simulation analysis of flow and temperature fields to determine the average temperature rise of the coil and the hot spot temperature seat, ensuring product performance.
By collecting key data such as temperature, current, voltage, vibration, and grid harmonics of transformers, online power quality analysis, fault alarms, and installation on mobile phones can be achieved.
Ordering Notice:
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