5.0 Transformer Equivalent Circuit
An Ideal Transformer has: -
- No losses.
- Perfect coupling between windings.
- Infinite open circuit impedance (No load current = 0 ).
- Infinite isolation between windings.
In reality, practical transformers show characteristics that differ from those of an ideal transformer. Many of these characteristics can be represented by a transformer equivalent circuit.
“Real” Transformer Equivalent Circuit
Transformer equivalent circuit
Ls and Rs are used to model the effect of core losses.
R1, R2, R3 are the resistances of the windings.
Ll is the leakage inductance.
C1, C2 and C3 are the inter-winding capacitances