Industrial sensorless control of induction motors

Abstract

In recent years, there has been an increased need in industry for high performance adjustable speed drives using an induction motor fed by a pulse width modulated voltage source. An important issue is the so-called “sensorless” control of the motor, i.e., the control without any mechanical (position or speed) measurements, relying only on the stator currents. This is a difficult control problem, both from a theoritical and practical point of view. We present experimental result achieved by the new Adjustable Frequency Controller ATV58-F of Schneider Electric SA. Its algorithm relies on “advanced” nonlinear control theory.