双凸极永磁电机无位置传感器

东南大学硕士学位论文ABSTRACTThe new DSPM motor drive system is a competitive candidate in variable-speed operation drive withhigh performance,attracting more and more attentions.The rotor position information of DSPM motordrive is essential to determining the switching sequence and the speed of the rotor.In this thesis,the key features of different sensorless control strategies are compared and theapplicability to the DSPM motor drive is analyzed.At last,back-EMF method is selected.The circuit ofrotor position detection and the main hardware and software for the control system are presented.Thecircuit of rotor position detection is comprised of isolated sample of the terminal voltage,the Butterworthsecond-order low pass filter,zero-crossing detection and optical isolated circuitry.According to the exactrotor position signals,the MPU calculates the rotor speed and position,and then the DDS produces thereferenced current wave.By using the developed control system,the DSPM motor operates in two-phaseoperation with sensorless control.Because of the lack of self-starting ability for the DSPM motor controlled by the Back-EMF method,the "Three-step Starting Technique"is analyzed and adopted to the DSPM motor..The rotor pre-setting,accelerating and state-changing step of three-step Starting Technique is discussed in detail.Base on theindependent control of each phase in DSPM motor,a new accelerating method,indirect-one-phaseoperation,is proposed.This method improves the reliability of starting technique greatly.Finally,a prototype drive system is designed and built,and experiments are carried out.The resultsverify the feasibility and correctness of the developed sensorless control system for the DSPM motor.Key words:DSPM motor,sensorless control,EMF zero crossing detecting method,StartingStrategy,indirect-one-phase operation