Sliding mode based stator flux and speed observer for induction machines

We extend current research into the sensorless control of induction machines by proposing a sliding mode based observer for flux and speed in induction machines. The usual models of induction machines use rotor fluxes and stator currents and any control algorithm using these states depends on motor parameters, which are usually uncertain. Sliding mode control offers parameter insensitive closed-loop dynamics, and this property can be followed, to the letter, with the development of the stator-flux and speed observer proposed in this paper.