2
$\begingroup$

If the secondary is an open circuit or the current taken from it is small, then to a good approximation $ ε_s = v_s$ where $ ε_s$ and $ v_s$ are secondary voltage(induced) and secondary terminal voltage.

Why does it said that terminal voltage will decrease at secondary of a transformer if we draw current?

Improve this question
$\endgroup$

1 Answer 1

Reset to default
1
$\begingroup$

The windings (wire) of a transformer have some electrical resistance; your secondary voltage will drop from the induced voltage (EMF) by the current times the secondary winding resistance as well as the (turns ratio corrected) primary winding resistance plus any source resistance.

Improve this answer
$\endgroup$
2
  • $\begingroup$ So can we see electrical resistance of secondary as internal resistance of a battery? $\endgroup$
    – user117954
    Commented Aug 20, 2016 at 13:59
  • $\begingroup$ Yes, the effect is similar to the internal resistance of other sources (like a battery). There are complications, due to the possibly nonlinear nature of the transformer core, in that the core magnetization losses may change the as-measured resistance (and the coupling between primary and secondary), especially if the AC has a broad frequency range. $\endgroup$
    – Whit3rd
    Commented Aug 20, 2016 at 15:43

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.