Research On Sliding Mode Control Method Of Permanent Magnet Synchronous Motor Servo System

Due to its high precision,fast response,and high efficiency,PMSM can be used more and more widely in civil and military applications.The control system of the PMSM is very complex and needs to solve the problems of multi-variable coupling,parameter drift,external interference,etc.Therefore,the research on the control method of PMSM is important.Theoretically,the sliding mode control does not require high accuracy of the system model,and it can still maintain robust robustness when the system parameters drift or external disturbances exist.Therefore,the sliding mode control can emerge in the industrial field.This paper will mainly discuss the application of sliding mode control in servo system,and design the corresponding actual measurement platform based on the theoretical results.Firstly,the model of PMSM is built,the projection and decoupling of the electrical parameters are achieved through the Clarke transform and the Park transform,after that,the model on the direct and quadrature axis components is obtained.On this basis,combined with the vector control principle,a simulation model was established,a PI controller was designed,and the control algorithm of the classic motor servo system was reproduced.Record the output of the simulation as comparison data in subsequent experiments.Subsequently,the article introduced a new idea by studying the sliding mode control algorithm based on the exponential approach law,and theoretically discussed the stability of this algorithm.Establish a simulation model and compare the simulation results with the PI controller.But in theory,sliding mode control will inevitably introduce high-frequency vibration.In order to effectively attenuate high-frequency dithering,this paper designs a sliding mode control algorithm based on the hybrid approach law from the theoretical perspective.The idea of this is to add the terminal sliding mode computation to the existing algorithm,and improve the movement quality of the system state point near the sliding mode surface,thereby reducing the chattering to some extent.Next,the paper studied the basic theory and properties of the fractional calculus operator,and apply this idea in the sliding mode control algorithm.Observe the performance of the new control algorithm in the simulation system,retain the data,compare and analyze the results of the previous simulation data.After completing the theoretical research and analyzing the requirements of the system,this paper designed the control board from both hardware and software perspectives.In terms of hardware,it covers the minimum system of the core digital chip,power supply module,inverter circuit,current sampling circuit,and serialcommunication circuit.Software,covering the initialization of the main program,and the realization of the algorithm and the solution of the electrical parameters in various interrupt service functions.Finally,this paper verify the correctness of hardware and software by using a designed experimental platform.The various controllers designed in this paper are implemented concretely,and the actual effects of various methods are compared.At the end of this paper,the unique advantages of the sliding mode control method in the servo system are proved.