Research On Sensorless Vector Control Of Permanent Magnet Synchronous Motor For Vehicles

Electric Vehicle provides an effective way to cope with the energy crisis and environmental pollution problem,Permanent Magnet Synchronous Motor(PMSM)has been widely used in many fields,bescause of its small size,light weight,high power density,low torque ripple.In order to achieve high-precision control effect,generally need to obtain rotor position and speed information from the mechanical sensor on the rotary shaft to realize closed-loop control.To get rid of the disadvantages of mechanical sensors and improve system reliability,sensorless vector control of permanent magnet synchronous motor technology has become a hot research.In this paper,high frequecy rotating voltage injection is used for zero and low speed,flux observer based on DSOGI-FLL and variable-structure model reference adaptive system(MRAS)observers are used for high speed,to realise sensorless vector contorl in the whole speed region.Mathematical model of PMSM is derived.Additionally,the parameters of closed current loop and closed speed loop are designed based on theoretical derivation.Simulation results show the correctness of parameters for vector control.Describes several methods for sensorless vector control of PMSM,and flux observer based on DSOGI-FLL and a variable-structure model reference adaptive system observers are used for high speed sensorless vector contorl.In order to weaken the shaking phenomenon of sliding surface,a sigmoid function is used to replace the original sign function.To obtain the rotor position and speed information at zero and low speed,basic principles of the high frequency voltage injection are analyzed.By using Luenberger observer to estimate the rotor position and speed to achieve sensorless control,simulation results show this sensorless control method is effictive.By analyzing the particularity of the stationary state,a simple method is proposed,only a low pass filter and rotating coordinate transformation is used,simulation results show the method has high accuracy.Designed the hardware circuit for the control system,such as three-phase bridge inverter,drivers circuit for IGBT,the sampling circuit of current,encoder conditioning circuit,and the conditioning circuit for process the singal for DSP TMS320F28335.Finally,experiments were carried out through the experimental platform of a 10 kW permanent magnet synchronous motor drive system,include the VVVF,sensor vector control,the sensorless vector control based on DSOGI-FLL,then verified the correctness of the theory.