Discussion on: 'Observer Scheme for State and Parameter Estimation in Asynchronous Motors with Application to Speed Control'

摘要

The objective of this discussion is to enlighten the most important features of the paper by A. Ticlea and G. Besancon and to outline some possible future developments and improvements. This paper deals with the simultaneous state and parameter estimation for induction motors. This is an interesting and challenging topic in the field of nonlinear control and estimation theory applied to electric drives, as testified by the detailed bibliography overview reported in the paper and in [1]. It is worth to point out that state and parameter estimation for induction motors is significant for various reasons. At least in their basic version, many high performance controllers, e.g. based on field oriented control, direct torque control, passivity-based control, feedback linearization, are designed under assumption of known and constant induction motor parameters. Moreover, it is known that various controllers are sufficiently robust to parameter mismatching; for example, in [2] it has been shown that the indirect field oriented control is quite robust with respect to rotor time constant mismatching, while in [3] an improved indirect field oriented control strategy shows increased robustness with respect to the standard version.