Research On 3D Measurement Method Based On Automatic Focusing Technology

Permanent Magnet Synchronous Motor(PMSM)is widely used in industrial production due to its advantages of high power density,high positioning accuracy and fast response speed.In the permanent magnet synchronous motor vector control system,it is more accurate The position information and speed information are the bridges for in-depth study of the motor system and play a vital role.Nowadays,many engineering applications add sensors to detect the position and speed of the rotor,but it will increase the efficiency of the transmission system and reduce the performance of the system.The sensor without position can estimate the position and speed information of the rotor online.Therefore,the sensorless control of surface-mounted PMSM permanent magnet synchronous motors has very important rationale and practical application value.First of all,after fully understanding the coordinate transformation,PMSM mathematical model and its vector control system principle,the principle of sliding mode variable structure used for PMSM rotor position observation is studied and analyzed.For the traditional sliding mode observer,the symbolic function will appear as the control function.Rotating speed observations have large jitters,and the use of low-pass filters and angle compensation links will increase the complexity of the system.They propose the use of a piecewise exponential function as the control function to suppress waveform jitter,and two filtering anti-jitter filtering to remove high-frequency signals.Interference is combined with the phase-locked loop algorithm to extract rotor position information to improve the traditional sliding mode observer.Secondly,in order to enhance the dynamic quality performance of the sliding mode observer,the approaching motion stage before reaching the sliding mode surface is studied,and a new approach law is proposed,which can reduce the chattering while increasing the approach speed and construct a sliding mode controller based on a new approach law is presented.Finally,after simulation comparison in Matlab / Simulink proves the superiority of improved sliding mode observer and sliding mode controller based on new approach law.The ST company’s STM32F103ZET6 control chip and intelligent power chip(IPM)are used to form a hardware control platform,and combined withthe software platform ST Motor Control Workbench for experimental verification,analysis and verification of the feasibility and effectiveness of the improved sliding mode observer in observing the speed performance.