Effect of the errors in the rotor position estimation on the stability of a Double Fed Induction Motor where the mechanical quantities are estimated by a MRAS

This paper deals with the stability of a sensorless drive based on a MRAS observer and on a double fed induction machine. An enhanced model of the whole system observer-control-machine is proposed. The model takes into account the difference between the real and the estimated rotor position and is exploited to perform a complete analysis of the stability under mismatch of the parameters. The theoretical results are validated by some experimental tests performed on a 3.7 kW machine.