Voltage transformer in GIS

[ravindranathan]

How is it possible to have such small size voltage transformer within 220kV GIS?
If we consider the ratio--220kV/110V and the turns that needs to be wound 2000--it is huge--still how do manufacturers manage to put it in such a small enclosure.

 

[Mbrooke]

Most voltage transformers (VTs) above 69kv have a capacitive potential divider which reduces the voltage before its fed into the iron core portion of the VT.

https://circuitglobe.com/capacitive-voltage-transformer-cvt.html

 

[cuky2000]

The main reason is that the GIS is enclosed in SF6 and dielectric clearance is significantly reduced compared with air. The AIS VT must have a large bushing to maintain the clearance between the energized part on top (xx kV) and the base tank at ground potential (V=0).

See the illustration below.