Research On Sensorless Control Strategy Of Electric Vehicle Permanent Magnet Synchronous Motor Based On Model Design

Permanent Magnet Synchronous Motor(PMSM)has been widely used in the field of electric vehicle because of its special advantages of efficiency.The working environment of electric vehicle motor is relatively harsh,and the rotary transformer or encoder which is installed in the motor spindle for detecting the rotor position belongs to the damageable parts,and the failure will cause serious safety accident.This paper will study the application of speed sensorless control strategy based on this issue.Aiming at the disadvantage of low development efficiency,long cycle and poor code reliability of the traditional motor control algorithm,this article will base on the model design to develop the control algorithm of the motor,realized the dynamic integration of the simulation and the hardware processor,and improved the reliability of the motor algorithm greatly.Firstly,this paper analyzes the structure and operating principle of permanent magnet synchronous motor,and derives the mathematical model of PMSM in different coordinate system according to the principle of coordinate transformation.Based on this,the working principle of the space voltage vector control algorithm of three-phase cascaded voltage source inverter is introduced,and built the model of PMSM vector control system.In order to realize speed sensorless control,the rotor speed and position are estimated by model reference adaptive algorithm,and based on the Popov hyper stability principle to design the self-adaptive regulation.Because the traditional model reference adaptive algorithm realizes the parameter identification through the stability convergence of the system,and the convergence speed is slow,therefore,in this paper,a full-step adaptive status observer is designed as an adjustable model,and added the corrective feedback loop in the state estimating equations,which greatly improves the convergence rate of speed identification and realizes the effective estimation of the position and speed of the motor.Then,the development process of model based design and combined with the vector control algorithm of permanent magnet synchronous motor,takes the Embedded Coder toolkit of MATLAB/Simulink as development tool to build the simulation model and code model of motor vector control,and set up the code model of speed sensorless algorithm.The method of model based design to realize the automatic code generation,Simulink graphical programming and the-loop simulation of processor,which can effectively to avoid code errors and modify them in time.Finally,this article introduces the design of the hardware experimental platform of PMSM control system,designs the main control system with TMS320f28377s as the core,which provides an experimental platform for the application of the algorithm proposed in this paper.On this platform,the paper tests the speed sensorless algorithm development by model based design and verifies the correctness of the algorithm and the validity of the model generating code.