Direct Torque Control with Space Vector Modulation (DTC-SVM) of ...
Direct Torque Control with Space Vector Modulation (DTC-SVM) of ...
Direct Torque Control with Space Vector Modulation (DTC-SVM) of ...
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<strong>Direct</strong> <strong>Torque</strong> <strong>Control</strong> <strong>with</strong> <strong>Space</strong> <strong>Vector</strong> <strong>Modulation</strong><br />
q − axis<br />
β<br />
δ Ψ<br />
Ψ s _ ref<br />
∆δ Ψ<br />
θ Ψ<br />
s<br />
Ψ s<br />
Ψ PM<br />
d − axis<br />
θ r<br />
Figure 5.1. <strong>Space</strong> vector diagram illustrating torque control conditions.<br />
α<br />
5.2 Cascade structure <strong>of</strong> <strong>DTC</strong>–<strong>SVM</strong> scheme<br />
The structure <strong>of</strong> proposed control scheme is shown in the Fig. 5.2. [11,33,42,48,51,53,54]<br />
U DC<br />
Ψ s _ ref<br />
U<br />
s α _ ref<br />
S A<br />
S B<br />
M e _ ref<br />
e M<br />
∆δ Ψ<br />
U<br />
s β _ ref<br />
S C<br />
θ Ψs Ψs<br />
I s<br />
M e<br />
I s<br />
γ m<br />
Figure 5.2. Cascade structure <strong>of</strong> <strong>DTC</strong>-<strong>SVM</strong> scheme.<br />
The error between reference and measured torque can be expressed as:<br />
Ψ Ψ sin( δ +∆δ ) Ψ Ψ sinδ<br />
eM = M − M = p<br />
− (5.3)<br />
3 s_<br />
ref PM Ψ Ψ<br />
_<br />
[<br />
s PM Ψ<br />
e ref e b<br />
]<br />
2<br />
Ls<br />
Ls<br />
From equation (5.3) we can see that the relation between torque error and increment <strong>of</strong> load<br />
angel<br />
∆δ Ψ<br />
is nonlinear. Therefore, we used PI controller which generates the load angel<br />
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