Determine Transformer KVA output and Power Factor

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The discussion focuses on calculating the KVA output and power factor of two transformers, T1 and T2, operating in parallel under a lagging power factor of 0.8. The impedances of the transformers are given as Za=0.04+j0.09 and Zb=0.01+j0.07, both rated at 3000 KVA. The user attempts to determine the KVA output for each transformer but encounters an error in their calculations, resulting in a total output of 3899 KVA, which is incorrect. Clarification is sought on the formula Za/(Za+Zb), which represents the impedance ratio of transformer T1 to the total impedance of both transformers. Understanding this ratio is crucial for accurate load distribution and KVA output calculations.
maluzha
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1. Two transformers T1 and T2 in parallel supply a common load at a lagging pf of 0.8, their per unit impedance are 0.04+j0.09 and 0.01+j0.07 at the same kva ratings of 3000KVA each and load power = 5500KVA

Determine the kva output of each transfromer and power factor

This is how i worked it:
Za=0.04+j0.09
Zb= 0.01+j0.07
Zt=0.05+j0.16

Za/(Za+Zb)= 0.048<66.04/0.168<72.65
=0.286<-6.61
Zb/(za+Zb)=0.071<81.86/0.168<72.65
=0.423<9.21
Sa=5500<-36.86*0.423<9.21 = 2326<-27.65
Sb= 5500<-36.86*0.286<-6.61 = 1573<-43.47

Sa+Sb gives a total of 3899kva which is wrong!
 
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Za should be .098<66.04

Why is it Za/(Za+Zb) don' understand this part.

Thanks
 
Za/Za+Zb is the ratio of Za to the total load
 

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