1.DBW1A family buried substation is the latest research and development, to fill the gaps for the construction of a new city power grids box-type substation.
2.DBW1A series Buried (box) 6 ~ 10kV substation as a communication network, rated frequency 50Hz, rated capacity of 50 ~ 630KVA transformer substation devices independent sets for urban high-rise buildings, residential quarters, factories, mines, hotels, parks, railway and temporary facilities, indoor and outside spaces; can save a lot of urban land, especially the small size of the low height of the ground segment, do not block the view and affect the landscape, ideal for placing on the sidewalk or street.
Rated voltage: HV: 6/10kV, LV: 0.4kV Capacity range: 30, 50, 63, 80, 100, 125, 160, 200, 250, 315, 400, 500, 630, 800, 1000, 1250, 1600, 2000kVA Frequency: 50Hz Phase: single-phase and 3-phase Vector group: Dyn11, Yyn0 Impedance voltage: according to national standards Operation environment: in the basement or the cellar Loss: reaching national standard S11 series parameters Enclosure protection level: IP68 Noise level:≤ 55dB
Waterproof consideration for basic design and fabrication
Top: ventilation holes have effective rain-proof and water-proof capabilities;Side: carry out surface treatment for sides by waterproof concrete materials so that water can not penetrate from sides;Bottom: install waterproof concrete bearing base for buried transformer that is 300mm higher than the pit bottom. At usual time, water flowing from the ground into the pit will enter the ring channel under the base so that it will not immerse the buried transformer. Lay sandy cobble at the bottom of the base so that water can penetrate into the ground more quickly. Buried type transformer can also operate when immersing in water for more than 0.5m for a certain period of time. It can withstand floods and can effectively improve the reliability of the power supply system. However, in order to ensure the safe and reliable operation of the transformer, it is suggested to check the water accumulation situation in the pit after floods and long time heavy rainfall and the rainy season. If there is too much water, pumping and cleaning should be carried out.
Buried type transformer - temperature rise control measures
The buried type transformer temperature rise control measures can be ensured by the following four ways:Transformer low temperature rise design, control the oil temperature at around 45K, far lower than the international regulated 60K;
|3||Rated current of load switch||A||630|
|4||Main circuit thermal current||kA||20|
|5||Main circuit dynamic current||kA||50|
|6||Rated making current of main circuit||kA||50|
|7||Rated active load breaking current|| ||630|
|8||Rated ring closed breaking current||A||630|
|9||5% of rated active load breaking current||A||31.5|
|10||Rated breaking current of cable charging||A||10|
|11||Rated no-load breaking current of transformer||A||1600KVAq|
|12||Rated breaking current of fuse||kA||31.5|
|13||Rated transfer current||A||1500|
|15||1min power frequency withstand voltage to earth/between phases/disconnecting fracture||kV||42/48|
|16||Lightning impulse withstand voltage to earth/between phases/disconnecting fracture||kV||75/85|
|17||Rated pressure of SF6 (20ºCsurface pressure)||Mpa||0.045|
|18||Annual leakage rate of SF6|| ||≤0.2%|