The equivalent impedance of the circuit as seen from points a and b is
 |
(23) |
For most induction motors (X1+Xc) is much greater than R1. Hence, R1 can be neglected from the denominator of equation 22 and equation 23 . The simplified expression for Veq and Zeq are
 |
(24) |
| (25) |
From the Thevenin's equivalent circuit, the rotor current can be determined as
 |
(26) |
 |
(27) |