S18-66kV dual winding on load tap changer power transformer |
额定容量
Rated capacity
(kva) |
电压组合及分接范围
Voltage ratio(kv) |
联结组
Connection symbol |
空载损耗
No-load loss
(kw) |
空载电流
No-load current
(%) |
负载损耗
Full-load loss
(kw) |
短路抗阻
Impedance(%) |
高压
HV |
高压分接范围
MV Tapping Range |
低压
LV |
6300 |
63
66
69 |
±8×1.25% |
6.3
6.6 10.5
11 |
YNd11 |
10 |
0.60 |
36 |
9 |
8000 |
12 |
0.60 |
42.7 |
10000 |
14.2 |
0.55 |
50.4 |
12500 |
16.8 |
0.55 |
59.8 |
16000 |
20.2 |
0.50 |
73.5 |
20000 |
24.0 |
0.50 |
89.1 |
25000 |
28.4 |
0.45 |
105.3 |
31500 |
33.7 |
0.45 |
126.9 |
40000 |
40.3 |
0.40 |
148.9 |
50000 |
47.6 |
0.4 |
184.5 |
63000 |
56.2 |
0.35 |
222.3 |
66kv Power Transformer Shipment

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66kv Power Transformer FAQ
Q1:What are the typical application scenarios of 66kV transformers?
Suitable for urban power grid main substations, industrial park distribution systems, new energy power stations (such as wind/photovoltaic booster stations), high-voltage power supply in mines, and rail transit, meeting the demand for medium to high voltage energy conversion.
Q2:What is the no-load loss range of a 66kV oil immersed transformer?
According to different capacities, the no-load loss range is usually from 0.36kW (small capacity) to 41.6kW (63MVA large capacity), and the use of high permeability silicon steel sheets can further reduce losses by 5% -15%.
Q3:Can 66kV power transformers operate in extreme low temperature environments (such as -40 ℃)?
Yes, most 66kV transformers are designed with a temperature range of -45 ℃ to+40 ℃, and the oil tank uses low-temperature oil (such as BIOTEMP ester oil) and antifreeze structure to ensure stable operation in cold regions.
Q4:How to choose the short-circuit impedance value for 66kV power transformers?
The standard short-circuit impedance is 8%~12%, which needs to be customized according to the short-circuit capacity and load characteristics of the power grid. For example, high impedance transformers (12%) are suitable for industrial areas with high short-circuit currents.
Q5:What voltage regulation methods are supported by 66kV power transformers?
*Off Circuit Tap Changer: ± 5% voltage adjustment, power outage operation required.
*On load voltage regulation (OLTC): ± 8 × 1.25% dynamic adjustment, suitable for scenarios with frequent voltage fluctuations.
Q6:How to prevent transformer damage during the transportation of 66kV power transformers?
*Fixed with steel wire rope, the fuel tank is filled with nitrogen gas protection (pressure 0.01~0.03MPa).
*The speed limit for land transportation is ≤ 50km/h, and sea transportation should avoid salt spray corrosion areas.
Q7:Does the 66kV power transformer require regular replacement of insulation oil?
The fully sealed transformer adopts a 30-year maintenance free design and does not require oil change; It is recommended to test the oil quality of conventional transformers every 5 years (breakdown voltage ≥ 50kV, water content ≤ 15ppm).
Q8:Is the 66kV transformer compatible with renewable energy grid connection?
Supporting the integration of fluctuating power sources such as wind power and photovoltaics requires on load voltage regulation and intelligent temperature control systems to cope with sudden load changes (such as the case of a certain offshore wind farm in China).
Q9:What are the requirements for the foundation when installing a 66kV power transformer?
*The basic load-bearing capacity should be ≥ 1.2 times the weight of the equipment, and the horizontal deviation should be ≤ 2mm/m.
*Outdoor installation requires reserved firewalls (distance ≥ 1.5m) and oil discharge tanks (capacity ≥ 100% oil volume).
Q10:How can 66kV power transformers cope with high-altitude environments (such as above 3000 meters)?
Customized capacity reduction design is required (with a 6% capacity reduction for every 1000 meters of elevation) and strengthened insulation (such as increasing the creepage distance of the casing to 3150mm).
Q11:Does the noise level of 66kV power transformers meet environmental standards?
No load noise ≤ 65dB (A) (taking 63MVA as an example), in compliance with
IEC 60076-10 standard. An additional soundproof cover can be installed to further reduce the noise level to below 55dB.
Q12:What are the contents of after-sales service for 66kV power transformers?
*Warranty period: usually 18 months after leaving the factory or 12 months after being put into operation (whichever comes first).
*Technical support: remote monitoring, fault diagnosis, and on-site maintenance (response time ≤ 72 hours).