Research On S-curve Acceleration And Deceleration Control Of Permanent Magnet Synchronous Motors For CNC Machine Tools

With the continuous improvement of China's economic level and people's living needs,domestic production and manufacturing have been developed rapidly.Especially in the field of numerical control machine tools,automobiles,ships and so on,motor control technology is developing faster and faster,which is also the core of modern manufacturing industry.However,in the manufacturing process,the application of motor control technology in CNC machine tools still has some problems,such as complex machining path,machine tool shaking,which seriously affect the quality of workpiece and machining accuracy of machine tools.Therefore,this subject takes the control system of permanent magnet synchronous motor for CNC machine tools as the research object,in order to improve the machining efficiency and accuracy of the processed parts,and ensure the smooth operation of CNC machine tools.Through the establishment of relevant mathematical models,the research on acceleration and deceleration control strategies,an S-curve acceleration and deceleration control method of permanent magnet synchronous motor is proposed.This method can promote the development of CNC machine tool motion control and has important engineering practical value.The main research contents of this project are as follows:First of all,aiming at the movement trend of CNC,this paper studies the system's motion smoothing processing strategy,analyzes three acceleration and deceleration strategies,including straight-line acceleration and deceleration,exponential acceleration and deceleration,and S-curve acceleration and deceleration strategies,describes the function process of curve's speed,acceleration and acceleration respectively with mathematical formula,and establishes the motion track of acceleration and deceleration strategy.The results show that the S-curve acceleration and deceleration control can guarantee the smooth movement of CNC better than the linear acceleration and deceleration control and the exponential acceleration and deceleration control.Secondly,the motor test system is studied.Firstly,the fuzzy PID control is introduced,and then the effect comparison between the fuzzy PID control and the traditional PID control is established.The result shows that the fuzzy PID control is closer to the ideal value than the traditional PID control.Finally,Matlab is used to simulate the experiment,analyze the control characteristics of S-curve acceleration and deceleration to the motor,and discuss the control effect of the motor.Finally,on the basis of S-curve acceleration and deceleration control,a new control algorithm is proposed.The algorithm can find sensitive points according to the analysis of curvature rise and fall area,and improve the control efficiency.In addition,in order to solve the complexity of S-curve acceleration and deceleration calculation,in the area of frequent acceleration and deceleration,this paper uses the trigonometric function method with low complexity to unify the planning of acceleration and deceleration,effectively reducing the frequent change of speed and the calculation amount of the system,and ensuring the real-time processing.The conclusion shows that the S-curve acceleration and deceleration control can effectively control the operation of CNC machine tools,and speed planning of S-curve acceleration and deceleration can get more flexible speed curve.On the basis of satisfying the performance,improve the processing quality and efficiency.