How does frequency affect KVA rating of a transformer?
If a 500 kva, 400 v, 60 hz t/f is to be operated on 50 hz
frequency then how will its KVA rating change?
a-increase
b-decrease
c-remains same
Also explain why do u think like that.
Answer Posted / jinboll
The transformer EMF equation shows that the EMF induced in the secondary or the primary side of a transformer is directly proportional to the product of the flux (Φm) through the transformer core and the frequency. This leads to the flux is proportional to E/f.
For example, the kVA rating of the 500v to 250v 60 Hz transformer will be smaller when used in Europe with a frequency of 50Hz. 500/60 = E/50, E is smaller than 500v on primary side. 250/60 = E/50, E is smaller than 250v on secondary side.
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