dissipated by the stator and rotor resistances) is important because the energy saving achieves economic
account, imposes the motor to operate at lower temperatures resulting in a longer life span and meets the environmental
pollution prevention standards. In many industrial drive applications the motor does not operate at the nominal point
since the load may change. Motor efficiency is maximal only when the drive operates at its nominal operating point.
Below this point (light load conditions), the excessively stored energy in the coil inductances unnecessary decreases
the motor efficiency due to the unbalanced copper and iron motor losses. The drive efficiency during light load
operation can be improved by the optimum air-gap flux level adjustment in accordance with the torque and speed demand