I want to know that can I change the existing arc furnace transformer which use vector group Ddo to Dy11?

sedthawutp [at] tatasteelthailand.com

 

Sedthawut... yes, assuming all phase-ends are accessible and reconnection is physically possible! However, it would result in a different voltage-ratio and different ultimate-capacity!

That is, the ratio for the Dd0 is HV/LV, while the ratio of the reconnected Dy11, becomes (HV)/(LV/Sqrt[3]), where HV and LV are the current primary and secondary line-voltages, respectively.

Regards, Phil Corso

 

Sedthawut... correction to my earlier reply:

For the Dy11 configuration the voltage-ratio is (HV)/(sqrt[3]xLV), where HV and LV are the original primary and secondary line-voltages assigned the Dd configuration.

For example, if the primary and secondary line-voltage ratio for the Dd xfmr was 33kV/600V or 55:1, then, the primary and secondary line-voltage ratio for the Dy11 configuration would be 33kV/~1kV or ~32:1.

Regards, Phil Corso