Pro and Con of Direct Torque Control (DTC) of Frequency Converters (VVVF drives)
As we know, Direct Torque Control (DTC) is more advanced than the other two control techniques of vector control (indirect torque control) and scalar control (V/F control)for frequency inverters (frequency changers, variable frequency drives).
The advantage of Direct Torque Control (DTC) of Frequency Converters (VVVF drives) is the fastest response time, elimination of feedback devices, reduced mechanical failure, performance nearly the same as the direct current (DC) machine without feedback, etc, compare to vector control and scalar control (v/f control).
The disadvantage of Direct Torque Control (DTC) is due to the inherent hysteresis of the comparator, higher torque and flux ripple exist. Since switching is not done at a very high frequency, the low-order harmonics increases. It is believed that the Direct Torque Control (DTC) can be implemented using an Artificial Intelligence model instead of the model based on mathematical equations. This will help in better tuning of the model and less dependence on the motor parameters.
