A squirrel cage rotor position control using control vector and current control.

Abstract

The principle of vector control of AC machine enables the dynamic control of AC motors, and induction motors in particular to a level comparable to that of a DC machine. The vector control of currents and voltages results in control of spatial orientation of the electromagnetic fields in the machine and has led to term field orientation (BLASCHKE, 1971). Field oriented control schemes provide significant improvement to the dynamic performance of ac motors. The usual method of induction motor position and torque control, which is becoming an industrial standard (CASADEI et al, 2002), uses the indirect field orientation principle in which the rotor speed is sensed or estimated by rotor position and slip frequency is added to form the stator impressed frequency. The presence of a current control frame regulator enhance the system performance, but have the drawback of increasing the project costs. This paper proposes a comparative study between indirect vector control using wether a current control frame regulator or not, giving the designer enough information for the best approach that fits in the project needs.