Research On Control Technology Of Permanent Magnet Synchronous Motor Without Speed Sensor

Permanent magnet synchronous motor has been applied to industry,agriculture and our daily life widely for the past few years,it has many advantages such as simple control structure,high power density,easy control and high accuracy.However,because the main part of the permanent magnet synchronous motor is composed of permanent magnets,it is highly necessary to gain the rotor position and the the motor speed information of the pmsm directly,we usually install a sensor or rotor position motion sensor inside these devices can be used to directly detect and obtain the rotor position and motor speed of the synchronous motor,to facilitate However,in many scenarios and locations it is not convenient to install a sensor to detect the position.Therefore,it is necessary to investigate the control of permanent magnet synchronous motors with different position sensors in the field of full speed.This investigation is also of great significance.This paper is constructed underline an introduction of the basic technology,to analyze the technical basis,design structure as well as the mathematical model of the permanent magnet synchronous motor.Deep comparisons of strength and weakness on various permanent magnet synchronous motors are to facilitate the selection of motors for subsequent simulations and experiments.In the end,the validation/verification of optimized PI parameters is in full accordance with the consequences of simulation.The study of PM synchronous motor without position sensor can be divided into two major categories: one for zero speed and low speed,and one for medium and high speed.Generally speaking,the sensorless control in medium and high speed uses the counter-electromotive force method to determine the rotor position in the PM motor,while in the zero speed domain and low speed domain,due to the relatively small counter-electromotive force,This essay is to ascertain the information of the rotor position using the high frequency injection method,therefore,the control in the zero speed and the low speed domain is able to be achieved.We analyze two high frequency injection methods and compare them,and finally choose the high frequency pulsation square wave injection method for simulation.After the successful verification of the zero and low speed and simulation experiments,the rotor position detection by the inverse electric potential method is carried out in the medium and high speed domain.After that,simulation is performed.In order to realize the full speed domain without position sensor control technology research,it is also necessary to carry out smooth switching from zero speed and low speed to medium and high speed domain.In other words,it is necessary to compound and control the two control methods,and to realize the smooth transition between them.In this paper,the weighting algorithm is briefly introduced,and the simulation is verified.Finally,a vector control experimental platform of permanent magnet AC synchronous motor based on rapid control prototype controller is established.Matlab simulation program is directly downloaded to the rapid control prototype controller by using matlab code generation function.Through the host computer controlling and driving the real main circuit and permanent magnet motor,the full speed sensorless vector control experiment is carried out.