POLITECHNIKA WARSZAWSKA

6. ANN sensorless Field Oriented Conrol of IM
It is easy to show, that IP controller is equivalent to PI regulator with the first order
filter in the input. The equivalent circuit is shown in Fig. 6.13.
r
T i
K p
T i
PLANT
y
Fig. 6.13. The equivalent of IP controller
Note that:
1. The controller tuned by the symmetry could be build using the IP structure
2. Where we add to the remain groups of PI controllers first order filter in the input
we can obtain lower overshooting. This give us the possibility to use IP regulator
with the same tuning criterions like in PI case.
6.5 Rotor and stator resistance adaptation
6.5.1 Introduction
The speed estimator, which is used in the system presented in Fig. 6.7. was
presented in section 5.3. It is easy to see that the following motor parameters have the
influence on this estimator:
• Rotor resistance r r ,
• Stator resistance r s ,
• Main inductance x M ,
• Leakage inductance σx s .
Two of these parameters x M and σx s do not vary with temperature, and can be
measured precisely. Therefore, the main problem is to make speed identification
robust to stator and rotor resistance variations. The solution of this task is to apply the
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