Position Sensorless Control Of Permanent Magnet Synchronous Motor Based On Adaptive System

Permanent magnet synchronous motor is the kind of motor which owns superiorperformance and are widely applied in many prospects. In the high performancecontrol system of permanent magnet synchronous motor, the rotor’s position andspeed information need to be detected accurately. The process of using mechanicalsensors to detect rotor’ position and speed information often takes a lot of problemssuch as the increasing cubage, weight and cost, the decreasing reliability, decreasingability to adapt to environmental deterioration and so on. The fast development ofsensorless control technique provides a good approach to solve these problems; and ithas the advantages of no changing motor structure, no using expensive positionsensor.Firstly, the development and control strategy of permanent magnet synchronousmotor and its sensorless technology were analyzed and introduced; then, thecoordinate conversion theory was introduced. A mathematical model of interiorpermanent magnet synchronous motor was set up under different coordinate systems,and the principles of space voltage vector PWM was described.Based on a depth analysis about the math mode of permanent mangnetsynchronous motor，a model reference adaptive sensorless control algorithm forinterior permanent magnet synchronous motor was proposed, to achieve thesensorless speed control of IPMSM. In this identification algorithm, the IPMSMactual current model was used as a reference model and the estimated current modelas an adjustable model, and the designed adaptive law for identification of speedreplaced the speed sensor. The two loop control of speed loop and current loop wasused in motion control system of interior permanent magnet synchronous motor.Based on the rotor field oriented vector control, the same dynamic performance as aDC motor can be obtained. The sensorless control system block diagram of interiorpermanent magnet synchronous motor was build.According to the above design of sensorless control system of permanent magnetsynchronous motor, the simulation model is constructed by using MATLAB/Simulinksimulation tool. From the aspects of high speed and low speed, the performance of thewhole system is analyzed in this paper; the results of the simulation system show thatthe regulating system based on model reference adaptive control can have gooddynamic and static performance in high speed.Finally, with using the TMS320F2812DSP control chip, the hardware systemand software sensorless control system of the interior permanent magnet synchronousmotor were designed.