Saturation effects in field-oriented induction machines

The important effects of saturation are outlined, and a simple first-order piecewise-linear representation of the saturation characteristic that explains these effects in an easy to understand manner is presented. Machine properties explored include saturation effects on available torque per stator ampere, practical limits on available torque and torque linearity, and a general analysis of the influence of parameter variations (detuning) in adjustable-flux systems. An experimental technique for evaluating the d-axis current level associated with peak torque per stator ampere in a saturated machine is also presented