Flux and speed numerical control of a voltage-fed asynchronous induction machine

The authors present the study and the realisation of a stator flux´s numerical regulation for a voltage-fed asynchionous machine. The stator flux is estimated by an observer that reconstitutes it from electrical variables measured on an experimental apparatus. The asynchronous machine works with its stator flux maintained constant during all the transient operating conditions; the electromagnetic torque is then proportional to the rotor-current angular frequency (¿¿), i.e. the system input. It follows that the entire process is a first-order system and that the speed regulation study is easy. The flux measurement and the flux and speed regulations are realised with numerical techniques.