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Equations

Module 4

Δ-Y Conversion:

Delta-Y Conversion
$$ Z_A = \frac{Z_1Z_2+Z_1Z_3+Z_2Z_3}{Z_1} $$ $$ Z_B = \frac{Z_1Z_2+Z_1Z_3+Z_2Z_3}{Z_2} $$ $$ Z_C = \frac{Z_1Z_2+Z_1Z_3+Z_2Z_3}{Z_3} $$
$$ Z_1 = \frac{Z_BZ_C}{Z_A+Z_B+Z_C} $$ $$ Z_2 = \frac{Z_AZ_C}{Z_A+Z_B+Z_C} $$ $$ Z_3 = \frac{Z_AZ_B}{Z_A+Z_B+Z_C} $$

For balanced loads: $$ Z_\Delta = 3Z_Y $$

Source Conversion:

Source Conversion
$$ E = IZ_p $$ $$ Z_s = Z_p $$
$$ I = \frac{E}{Z_s} $$ $$ Z_p = Z_s $$

Determinants: $$ D = \begin{vmatrix} a_{11} & a_{12} \\ a_{21} & a_{22} \end{vmatrix} = a_{11}a_{22} - a_{12}a_{21} $$