Research on a New Algorithm for Direct Torque Control of Induction Motor

A new algorithm is put forward for direct torque control (DTC) of induction motors.By calculating the increment of stator flux linkage vector,the algorithm tries to diminish both the difference between the reference and the actual torque output,and the difference between the reference and the actual flux linkage magnitude.In order to implement the algorithm,a linearization method is applied in an extremely short sampling cycle to calculate the increments of torque and flux magnitude,to derive the linear equation between the desired stator flux linkage vector increment angle and the increments of torque and flux magnitude,to derive the stator voltage vector reference and to determine the next position of the stator flux linkage vector.Neither trigonometric functions nor coordinate transformations is involved in this algorithm,and it is easy to realize the algorithm.A Matlab/Simulink-based simulation verifies the effectiveness of the algorithm.