2. Reconstitution of rotor flux

Up to now, we have assumed that the rotor flux of the asynchronous cage machine is a measurable quantity. In some applications, Hall-effect sensors are used to directly measure the flux in the air gap, but in the majority of cases, these sensors are outlawed and estimation and observation techniques must be used.

• Open-loop estimation

One solution for estimating rotor flux, illustrated by the diagram in figure 7 , is to reconstruct or simulate the electromechanical behavior of the drive by means of a mathematical model represented in the form of equations of state (see