A. Same as the steady-state magnetizing current.
B. Once the steady-state magnetizing current provided to the core has huge residual flux.
C. Same as the dynamic magnetizing current.
D. Mostly, the steady-state magnetizing current relying upon the initial state of the residual flux in the transformer core.
Answer: D
Explanation:
B. Once the steady-state magnetizing current provided to the core has huge residual flux.
C. Same as the dynamic magnetizing current.
D. Mostly, the steady-state magnetizing current relying upon the initial state of the residual flux in the transformer core.
Answer: D
Explanation:
Transformer on no-load:
- Whenever a transformer is on no-load, the secondary winding has no load connected to it.
- The transformer must actually withdraw zero current from the primary side.
- But practically even on no-load, a small amount of current is drawn from the primary side, to set up the required magnetic flux in the magnetic core.
- At no load, the transformer draws some current (Im) in order to establish the flux in the transformer core which lags the applied voltage by 90° ( since flux is required to create a magnetic pool in order to transfer energy from one port to another) called as magnetizing current.
- It is several times the steady-state magnetizing current, depending upon the initial state of the residual flux in the transformer core.
- This magnetizing current (no-load current) is about 3-5% of the full load current and it accounts for the losses in a transformer.
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