Abstract:

The traditional direct torque control of induction motor has a disadvantage. The ripple of flux and torque get increased when the system run at a low speed. After analyzing the reasons, a novel direct torque control of induction motor using sliding mode control and SVPWM(Space Voltage Pwlse-Width Modulation) is
presented. The sliding mode controller contributes to the robustness of system by reducing the influence of disturbances and uncertainties. The space voltage PWM(Pwlse-Width Modulation) modulation is used to produce the desired space voltage vector and decrease the ripple of flux. We use speed sensorless technology to improve in dustrial applicability of the system. In Matlab/ Simulink circumstance, the results of simulation prove that the novel direct torque control system reduces the ripple of flux and torque effectively and gets accurate speed.

Key words: induction motor, direct torque control, sliding mode controller, space voltage Pwlse-Width modulation(SVPWM), speed sensorless