Stator Flux Oriented control of induction motors using variable-saturation regulators

This paper proposes a stator flux oriented (SFO) control scheme of induction motors using variable-saturation regulators. The traditional SFO control scheme consists in the d-axis current component, torque, stator flux, and speed loops with four PI-type controllers. The proposed control scheme uses two regulators with variable-saturation in such a way that maximum dc-bus voltage utilization is reached and overcurrent problems are prevented. The experiments are carried out using dSpace digital controllers and show that the SFO control scheme, using variable-saturation regulators, guarantees the best dynamic performance in the field-weakening region with maximum dc-bus voltage utilization and without current overshoot.