IM Direct Torque Control with no flux distortion and no static torque error
Abdesslam Lokriti1, Issam Salhi2, Said Doubabi2
1Laboratory of Informatics, Systems, Electrical, Networks and Telecommunications, Univ Hassan 1, LISERT-ENSA, Boulevard Béni Amir, BP 77, 25000, Khouribga, Morocco.
ISA Transactions
|September 23, 2015
Summary
This study enhances direct torque control (DTC) for induction motors by using two hysteresis controllers for stator flux components. This novel approach reduces harmonics and eliminates static torque error, improving motor performance.
Area of Science:
- Electrical Engineering
- Control Systems
Background:
- Direct Torque Control (DTC) is a popular method for controlling induction motors.
- Classical DTC strategies can suffer from flux and current harmonics and static torque errors.
Purpose of the Study:
- To improve the performance of DTC control strategies for induction motors.
- To address harmonic distortions and static torque errors inherent in traditional DTC.
Main Methods:
- Implementing two hysteresis controllers for both real and imaginary stator flux components.
- Developing a novel, compact switching table independent of sector determination and avoiding zero voltage vectors.
- Introducing a PI-type controller to eliminate static torque error.
Main Results:
- Significant reduction in flux and current harmonics caused by sector exchanges.
- Theoretical validation of static torque error in classical DTC.
- Successful cancellation of static torque error using the proposed PI controller.
- Validation through simulations and practical implementation on a DSPace 1104 board for a 1.5 kW induction motor.
Conclusions:
- The proposed DTC strategy offers improved performance with reduced harmonics and eliminated static torque error.
- The novel switching table is more efficient and simpler than existing methods.
- The strategy is robust and validated for practical induction motor control applications.
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