What is Three Phase power transformer winding proceger ?

Dear Upinder  Kumar Kushwaha Munna,

If we are to design or manufacture an EHV or HV application power transformer then we have to take into consideration the application for which it will be used like power producer or the consumer or needed for on-grid solution  etc. especially the Capacity in KVA and the vector group selection is considered as very important.

It depends upon the application that the transformer uses Primary as Delta or Star and Secondary as Star or Delta or Zigzag etc.

The winding for HV / EHV is specially treated with a very high dielectric strength Insulation epoxies and kept pressurized with the use of SF6 gas for keeping the interior of EHV transformers insulated as possible and the SF6 Gas pressure is consciously being Monitored through transformer protection relays along with numerous other protections so as to keep the winding work safe as possible.

For more in-depth analyses I recommend the link for you https://electricalnotes.wordpress.com/2012/05/23/vector-group-of-transformer/

Thanks

    this my Q: