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Anonymous Poster #1

# Transformer

09/23/2017 6:16 AM

How the transformer reactive losses (in kVAr) is been calculated?

Thanks !!

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#1

### Re: Transformer

09/23/2017 11:25 AM

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#2

### Re: Transformer

09/23/2017 6:33 PM

Here is an example that might help.

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#3

### Re: Transformer

09/24/2017 10:13 AM

If I remember right it's KVA*sin(φ) where φ = acos(PF).

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#4

### Re: Transformer

09/27/2017 12:44 PM

If we neglect the resistance and consider Z=X then

Q=usc*S^2/Sn*(Vrat/V)^2 where

Q[MVAR] usc=usc%/100 =transformer short-circuit voltage

S actual apparent power [MVA] Sn=rated power[MVA] Vrat =primary rated voltage[kV] V=actual supply voltage [kV]

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Julius
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#5

### Re: Transformer

11/02/2017 4:27 AM

I usually do not think about it and just use automatic caculator from website to get the result of KVA and KW.

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