Research On Control Strategy Of Open-winding Permanent Magnet Synchronous Motor

In recent years,with the continuous improvement of the driving power of electric vehicles,traditional motors have gradually failed to meet people’s needs.Open-winding permanent magnet motors have gradually attracted people’s attention with their excellent characteristics.The open-winding permanent magnet synchronous motor is based on the traditional permanent magnet synchronous motor.The neutral point of the motor is opened,and an inverter is connected at both ends.Compared with traditional permanent magnet synchronous motors,open-winding permanent magnet synchronous motors can output higher power,Among them,the independent DC bus type drive system requires two power supplies,which increases the volume and cost of the system,but the common DC bus type drive The system has a common-mode voltage problem,so this article adopts an SVPWM method that eliminates the common-mode voltage,taking advantage of the unique advantages of vector control,thereby eliminating the common-mode voltage generated by the common DC bus drive system.First,analyze the advantages and disadvantages of the two topologies commonly used in open-winding permanent magnet synchronous motors.After careful comparison and analysis,the common DC bus-type drive system is selected as the key research content.After introducing the traditional vector control principle,Make improvements to apply to the dual inverter topology.Secondly,When the common DC bus-type drive system is adopted,its special structure provides conditions for the generation of zero-sequence loops.The commonmode voltage acting on the zero-sequence loop will gradually increase the zerosequence current,thereby affecting the performance of the motor and reducing Its life.Therefore,after analyzing the SVPWM control method,this article adopts a vector control method that can eliminate the common-mode voltage and conducts experimental simulation on it.The simulation results show that this method can effectively eliminate the common mode voltage generated by the system,thereby suppressing the generation of zero sequence current.This method can still ensure the smooth operation of the motor and has good performance.Then,this paper studies the motor single-phase open-circuit fault of fault-tolerant control for double inverter control system,when the system fails,the traditional research mostly from the perspective of increasing hardware based on voltage vector control method,in this paper,by adjusting the rest of the two phase bridge to the opencircuit fault analysis of a phase bridge arm arm switch state inverter can output round rotating magnetic field,thus motor under fault condition to realize fault tolerant operation,to avoid the increase and saves the cost of hardware parts On the basis of theoretical analysis,the simulation model of unwound PMSM is established by Simulink,and the control strategy proposed in this paper is verified.Finally,we set up a hardware system.The processor of this system is of the STM32 series.This is a series of single-chip microcomputers.Our hardware circuit has many parts.I have introduced them in the article.After the experiment,we got a lot of Waveforms,these waveforms are very important and play a role in theoretical support.