Research On Speed And Position Detection Algorithm Based PMSM Sensorless Control

Permanent magnet synchronous motor(PMSM) is widely used in various fields, and has a broad development prospects because of its superior performance. Accurately obtaining the motor speed and position of the permanent magnet synchronous motor is of vital importance. The mechanical sensor is widely used in traditional control system to detect the rotor information, such as tachometer generator, photoelectric encoder and so on, this increases the cost of motor, reduces the reliability, and also limits the use of the motor. Therefore, using the algorithm of observation to estimate the current voltage for the motor rotor information instead of the traditional sensor has become a hot research topic. This paper uses the sine wave driven surface PMSM as the research object, studying the three methods to obtain its speed and position, respectively according to different speed range for speed and position observation.This paper in detail introduces the PMSM speed and position observation algorithm researching status, and gives the vector equation of permanent magnet synchronous motor and the mathematical model of the coordinates, as well as the method of PMSM vector control and realization of SVPWM.Secondly, for the high speed period, method based on sliding mode observer is discussed in detail and the traditional sliding mode observer is improved. At the same time, this paper also studies the algorithm based on model reference adaptive using in speed and position observation in detail, and respectively set up simulation model in MATLAB/simulink, and the simulation results are analyzed in detail. Due to the low speed under the counter electromotive force is too small, other methods need to be used. So in view of the low speed, Fluctuating high-frequency signal injection method is discussed, and the feasibility of the algorithm is verified by simulation, and the simulation results are analyzed.Finally, the paper uses the digital signal processor(DSP) TMS320F28069 as the core of hardware control platform to develop the core software for realizing the rotor information observer, discretization method and the early stage of the discretization method of improved SMO are proposed,and analyze the given experimental waveforms.