What is the equiv Z of 3 single phase XFMR connected in 3 phase
What is the equiv Z of 3 single phase XFMR connected in 3 phase
(OP)
When connecting single phase XFMR to make a 3 phase system, the impedance of single phase XFMR should be the same to prevent imbalance. However in this scenario I have
XFMR1=5.6%Z
XFMR2=5.76%Z
XFMR1=5.8%Z
What would the equivalent be?
Do you average them out?
Also one other question that I have been wondering for a while: suppose you have two 3 phase XFMRs. Can you connect them in parallel to increase the power capacity. Ie if you have two 1000kVA D-Y 3phase XFMR at 5.5%Z. Can you connect them in parallel to make it an equivalent 2000kVA D-Y XFMR?
XFMR1=5.6%Z
XFMR2=5.76%Z
XFMR1=5.8%Z
What would the equivalent be?
Do you average them out?
Also one other question that I have been wondering for a while: suppose you have two 3 phase XFMRs. Can you connect them in parallel to increase the power capacity. Ie if you have two 1000kVA D-Y 3phase XFMR at 5.5%Z. Can you connect them in parallel to make it an equivalent 2000kVA D-Y XFMR?






RE: What is the equiv Z of 3 single phase XFMR connected in 3 phase
RE: What is the equiv Z of 3 single phase XFMR connected in 3 phase
Short answer to both of your questions is yes.
For all practical purposes (neglecting imbalance), you can use average Z% of the 1ph units for a 3 phase bank. The %Z of a 3 phase machine is a single phase value as all 3 phase analysis is essentially done on per phase basis.
You can parallel the two trasnformers of equal or unequal impedances and/or sizes, just have to be careful of circulatiing currents and not overloading one of the units.
Although it is very helpful if the % impedances are closely matched to minimize the nuisance of circulating currents and proper load sharing.
RE: What is the equiv Z of 3 single phase XFMR connected in 3 phase