Direct Torque Control with Space Vector Modulation (DTC-SVM) of ...

Control methods of PM Synchronous motor
and those of the torque controller as
where
d = 1(increase torque) for M > M
_
+ H
(4.5a)
M e
e e ref m
d = 0 (decrease torque) for M < M
_
− H
(4.5b)
M e
e e ref m
H
m
and H Ψ
are hysteresis bands for torque and flux, respectively.
The digitized variables d Ψ
, d and the stator flux position sector γ M
s( N )
information
s
e
create a digital word, which select appropriate voltage vector from the switching table.
Next, from the selection table the proper voltage vectors are selected and the gate pulses
SA, SB,
S
C
to control the power switches in the inverter are generated.
The circular stator flux vector trajectory can be divided into six symmetrical sectors
(according to the non zero voltage vectors), which are defined as (see Fig. 4.11):
sector 1 − 30°≤ γ s
< 30°
V 3 (010)
V 2 (110)
sector 2 30°< γ s
≤ 90°
sector 3 90°< γ s
≤ 150°
sector 4 150°< γ s
≤ 210°
sector 5 210°< γ s
≤ 270°
sector 6 270°< γ s