Control of Induction Machine Drives

Abstract

In this chapter, attention is given to the control concepts that can be used to achieve independent torque and flux linkage control of induction machines over a wide speed range. First, classical V/f control concepts with very limited dynamic performance capabilities will be discussed. Next, field-oriented control techniques will be discussed. A key role is assigned to the presentation of a universal field-oriented (UFO) model which is used in conjunction with a current source induction machine model. At a later stage, this model is replaced with a voltage source induction model which is connected to a synchronous current-controlled converter. Finally, attention is given to the operational aspects of the drive which takes into account the maximum supply voltage and current constraints. In this context field weakening techniques are also discussed.