- Ideal Transformer Definition: An ideal transformer is defined as a theoretical transformer with 100% efficiency and no losses.
- Core and Copper Losses: In an ideal transformer, there are no core losses or copper losses, ensuring perfect efficiency.
- Purely Inductive Windings: The windings are considered purely inductive, meaning they have no resistance, which is key to the ideal model.
- Magnetizing Current: The primary winding draws a magnetizing current that creates an alternating flux in phase with the current.
- Mutual Induction: The flux in the primary winding induces an EMF in the secondary winding through the core, showing the principle of mutual induction.
Definition of Ideal Transformer
An ideal transformer is a theoretical machine with no losses: no core loss, no copper loss and no other dissipation. Its efficiency is 100%.
Ideal Transformer Model
The ideal transformer model treats the windings as purely inductive and the core of the transformer as loss-free. It also has zero leakage reactance of transformer (reactance is opposition to the flow of current from a circuit element because of its inductance and capacitance).
So all of the flux stays in the core and links both windings. Real windings have resistance and cause voltage drops. In an ideal transformer the windings are taken as fully inductive with zero resistance.
Apply an alternating source voltage V1 to the primary. A counter self EMF E1 appears in the primary, 180o out of phase with V1.
To set up that counter EMF (E1), the primary draws current from the source to make the magnetizing flux. Because the winding is purely inductive, this magnetizing current (Iμ) lags the supply by 90 degrees.
The alternating magnetizing current Iμ produces an alternating flux Φ. Flux is in phase with the current that produces it. The same flux links the secondary through the core, so an EMF E2 appears across the secondary. That is the mutually induced EMF in the next figure.
