POLITECHNIKA WARSZAWSKA

5. Speed estimation of induction motor
u s
Reference
Model
x
i s
i s
Learning
ε
ANN
∧
x
ω^m
Algorithm
Fig.5.8. Block scheme of an on-line ANN based speed estimator
As Adaptive Model the one layer linear ANN is used. More detailed description of
this approach is shown in the next section.
In the off-line approach a three-layer feedforward ANN is used, and the
mechanical speed is the output of the neural network. The input vector to the ANN
could be as follows:
xin
= [ u
sα
(
i
k)
sα
(
k)
u
sβ
(
i
k)
sβ
(
k)
u
sα
(
i
sα
(
k −1)
k −1)
u
i
sβ
(
sβ
(
k −1)
k −
T
1)]
(5.15)
The block diagram of this approach is presented in Fig. 5.9.
Because of the its simplicity, and the advantages of an ANN in the further part
of this thesis only approaches based on ANN are detailed described and used in real
system.
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