The Direct Torque Control of Brushless DC Motor Based on Position Sensorless Control Method

The direct torque control(DTC) has a lot of advantages such as simple control structure,good dynamic and static performance,rapid torque response.According to the characteristics of brushless DC motor,the flux hysteresis controller could be ignored in the constant torque region.The proper stator voltage space vector was selected based on the output of the torque hysteresis controller and the sector that the current rotor flux located in.The sector signal was detected through the back electromotive force superposition method.Through this method,the research about the application of DTC in BLDCM under the position sensorless control method was realized.Simulation results show that this method can minimize the torque ripple of BLDCM effectively,gain rapid dynamic response with position sensorless.