MODULE 4 — 3-Phase Transformer
4.1 Winding Connections & Vector Groups
Star-Star (Yy0 - 0° Shift)
$$ V_{line} = \sqrt{3} V_{phase} $$
$$ I_{line} = I_{phase} $$
HV Phasor
LV Phasor
4.2 Parallel Operation
Load Sharing
$$ I_A = \frac{Z_B}{Z_A + Z_B} \times I_{total} $$
$$ I_B = \frac{Z_A}{Z_A + Z_B} \times I_{total} $$
4.3 Scott Connection
$$ N_{main} = N, \quad V_{main} = V $$
$$ N_{teaser} = \frac{\sqrt{3}}{2}N = 0.866N $$
$$ V_{teaser} = 0.866 V_{main} $$
Converts 3-phase to 2-phase with 90° phase difference.