Design Of Starting Control Device For Sensorless Burshless DC Motor

Brushless DC motor(BLDC)has become an important movement in the modern industrial equipment parts,no commutation spark,brushless DC motor has a long service life,reliable operation,convenient maintenance,thus in the automotive,aerospace,household appliances and other industries has made a wide range of applications and development.The traditional brushless DC motor is often used for external position sensor for testing.The existence of the rotor position sensor greatly limits the application range of the brushless DC motor.To promote the further development of brushless DC motor,in almost every field of national economic development,it is necessary to overcome the above shortcomings.This article is mainly for designing the sensorless brushless DC motor control device.Firstly,analyze of the composition of the brushless DC motor structure,working principle and operation characteristics,to establish the mathematical model of brushless DC motor.Based on the back EMF method,this design mainly analyzes the three-step as starting control method of the design.Based on theoretical analysis,TMS320F28335 is designed for sensorless brushless DC motor control system hardware and software to control processes.Hardware is mainly composed of position detection module,modules,power modules,and power modules,software control flow includes the main program,subroutine,counter electromotive force zero-crossing detection procedures and systems to protect programs.Based on double closed loop control system,setting up in MATLAB/Simulink without position sensor model of brushless DC motor control system,and in the light,abrupt change of load and loading processes during the load starting of the three different cases simulation experiment,at the same time observe proceeds of the motor rotation speed,torque and starting current waveform.From the simulation results,the sensorless brushless DC motor starting device can achieve the desired effect.Finally in the building of experimental platform of brushless DC motor without position sensor starting control experiment,and analyze the results.The results show that based on DSP sensorless brushless DC motor staring control device has high control precision,strong reliability and feasibility,for the further development of brushless DC motor,has laid a solid foundation,has the high application value.