Improving the dynamic response of FOC induction machines operated with reduced rotor flux

This paper proposes a method to improve the efficiency of field oriented controlled induction machines. It is possible to increase the efficiency of machines which operate with light load levels for extended periods of time by reducing the flux level. The dynamic response of the FOC will depend in this case on the capability of the control to magnetize rotor when the torque must be increased. Such capability can be seriously compromised due to the inverter current limits, as well as due to voltage limits which can affect to the current regulator transient response. A method to improve the transient response of the drive under current constraints is proposed in this paper.