Analysis And Research On AC Stepper Control Efficiency With PMSM

As the major power equipment in the fields of economic social,motor plays a key role in thedrive systems since its emergence. According to realtive statistics,more than half of the totalelectrical energy in the developed countries was converted into mechanical energy by motor.While in our country consumption by various types of motors accounts for about65%.Minimizing the power consumption of the motor is of great significance for energy conservation.And Our country also has listed motor system energy-saving as one of Top10energy savingprojects, Simultaneously,our country has developed energy efficiency indicators for themotors,so that energy efficiency of the major energy-consuming equipments can reach orapproach international level,some can reach the international advanced level.The key idea of the vector control theory is simulating the control of the DC motor torquewith the three-phase AC powered motor by the coordinate transformation.That is on the fieldoriented coordinate, the current is decomposed into two parts, one part is used for generating amagnetic field with the magnetic flux of the motor, the other part generating the torque. Andmake sure the two components are perpendicular to each other and independent of each other, sothat we can easily control the torque, and obtain high-performance dynamic characteristics whichis similar to the DC motor, it is a breakthrough for the speed control theory of AC motor.AC stepper control technology based on the vector control theory,combined powerelectronics technology,computer control technology as well as stepper drive technologyorganically,make the continuous rotating air-gap magnetic field of the synchronous motor into adiscrete step magnetic field. So we can control the discrete step magnetomotive force,then get agood speed control,and further obtain accurate position control.This paper firstly conduct the theoretical analysis and research on relationship about themagnetic field of permanent magnet synchronous motor,efficiency and torque,Obtaining themathematical models of permanent magnet synchronous motor in common coordinate systemand the d-q coordinate system. Meanwhile,we build a finite element simulation model for themotor with Ansoft Maxwell,and also we conduct the simulation in VC mode and AC steppercontrol, comparing the pros and cons of two control modes, giving the different current under thedifferent load demand to meet the efficiency and energy-saving purpose by analyzing themagnetic field of the motor simulation.