Explain the equivalent circuit of an induction motor.

The per-phase equivalent circuit models the induction motor for analysis. Primary side includes stator resistance R1 and leakage reactance X1. The magnetizing branch (shunt) has magnetizing reactance Xm and core loss resistance Rc. Secondary (rotor) side, referred to stator, has rotor resistance R2/s and leakage reactance X2. The term R2/s represents both rotor copper loss (R2) and mechanical power developed (R2(1-s)/s). At s=1 (starting), circuit impedance is lowest; at s near 0 (no-load), R2/s approaches infinity.