ABSTRACT:
This paper proposes a method of applying the Space Vector
Modulation technique for Direct Torque Control (DTC) of a permanent magnet
synchronous motor (PMSM) drive. By this method it is preserved the principle of
the conventional DTC regarding the decoupled torque and flux control, while
providing more flexibility for the inverter voltage utilization, in order to
compensate the torque and flux errors in a smoother way than conventional DTC.
For this purpose, a reference voltage space vector is calculated every sample
time, using a simple algorithm, based on the torque error and the stator flux
angle. Numerical simulations have been made to test the proposed method and
results are presented.
KEYWORDS:
1. Direct Torque Control
2. permanent magnet
synchronous motor
3. Space Vector Modulation
SOFTWARE: MATLAB/SIMULINK
BLOCK DIAGRAM:
Fig. 1 Block diagram of the conventional DTC
EXPECTED SIMULATION RESULTS:
Fig. 2 Classic DTC, at 100 rpm
Fig. 3 Classic DTC, at 1000
rpm
Fig. 4 DTC with voltage control using the proposed method, at 100
rpm
Fig. 5 DTC with voltage control using the proposed method, at 1000
rpm
CONCLUSION:
In this paper it was presented a method of utilisation of Space
Vector Modulation for the Direct Torque Control of a PMSM. For this purpose, at
every control sample time a reference voltage vector is calculated and applied
to the inverter using SVM. To determine the reference voltage, a simple
algorithm was proposed, based on the torque error and the flux phase angle.
The results
show that a smooth steady state operation was obtained when using the proposed
method. Moreover, a constant inverter switching frequency is ensured by using
SVM.
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[1]
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C., Boldea I., and Blaabjerg F., Variable-Structure Direct Torque
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