Research Of Direct Torque Control For Induction Motor

In recent years, AC motor drive control with extraordinary prosperity has been developed rapidly and been researched widely and deeply for the special excellent characteristics.The paper analyzed the traditional theory of AC motor drive control, through computer simulation for DTC (direct torque control) and vector control, which testified that DTC is another great development after vector control in the field of AC motor drive control. Based on the space voltage vector modulation, a new scheme of polygon voltage vector control has been presented, which with the stator flux orientation developed a novel way of estimating the stator flux. A full digital driving circuit for inverter and a set of experiment system have been developed. It has been testified that the experiment system is rational on the hardware combination and software program via many experiments on a 5.5KW AC motor. A lot of experiments for open loop control and closed loop control have been made according to the polygon voltage vector control. The experiment result shows that the new scheme is feasible. At last, the result of harmonic analysis for current data saved in experiments has been described.