Research On Sensorless Vector Control Of Synchronous Reluctance Motor

Vector control technology solves the control coupling problem of AC motor,simplifies the corresponding control schemes and breaks the monopoly of the DC motor in the speed control applications.The AC motor speed system has been widely applied in industry.As a new type of motor,synchronous reluctance motor(SynRM)has attracted much attention in recent years because of its simple manufacturing,low cost and high efficiency.It has broad application prospects in the field of high efficiency drive,electric vehicle and so on.At the same time,sensorless control,which can reduce the cost of the system and the volume of system,is a hot topic.In this paper,the sensorless vector control of synchronous reluctance motor is studied,and the controller design and the flux observer technology are discussed in detail.Small signal modeling is carried out for different observers,and the stability of the observers are analyzed.A simulation model based on MATLAB-Simulink is designed,and the control scheme is simulated.Firstly,through the analysis of synchronous reluctance motor,a motor model based on rotor position orientation was established in this paper.On this basis,the corresponding control loop was set up,the parameter design was completed,and the corresponding vector control scheme of the synchronous reluctance motor was obtained.A module simulation model based on MATLAB-Simulink toolbox and a hardware in the loop simulation system platform based on dSPACE were established,which laid the foundation for realizing the speed tracking and power output of motor system.The control scheme was verified through the simulation and experimental platforms.Secondly,the application of three kinds of mainstream observers(voltage current model observer,full order observer and voltage type observer)in the system were studied.The specific parameters of the observer were designed by mathematical deduction.The rationality of the design ass verified by simulation,and it worked well in the normal operation range of the motor.Based on the linear theory,the corresponding three small signal models were established,and their stabilities were analyzed.It is found that the voltage current flux observer exists unstable region in the low speed power generation area.The full order observer is stable,but requires a lot of mathematical operations.By analyzing,the voltage type observer for synchronous reluctance motor is improved,which enhances the sensitivity of the parameters.Finally,based on the voltage-current model observer,a sensorless vector control system on the rotor position orientation was established.The identification of inductance parameters used in voltage current model observer was analyzed concretely,and the ripple of estimated speed caused by DC bias in the experimental platform is optimized.The results of mathematical analysis were verified by simulation and experimental platform,and flux linkage observation and speed estimation are evaluated.At last,sensorless vector control of synchronous reluctance motor is realized and the performance of the system is optimized by the inductance fitting and the de DC bias module.