Application Of Sliding Mode Control In Induction Motor Speed Control System

With the development of society,induction motor still play an important role in industrial and agricultural production and daily life,but their speed control systems are increasingly unable to meet people’s requirements.Traditional control methods have caused many problems due to many system variables,strong coupling ability,and nonlinearity.Based on the vector control of induction motor and sliding mode control method,the sliding mode speed controller and the sliding mode speed observer are designed to further improve the performance of the motor speed control system.The specific research contents are as follows:Firstly,taking the induction motor as the research object,the mathematical model of the motor in the three-phase stationary coordinate system is established.The mathematical model under the two-phase static and two-phase rotating coordinate system is obtained by coordinate transformation,and the vector control principle is introduced,Provide a foreshadowing for the next research work.Secondly,in order to further improve the performance of the induction motor speed control system,ensure global fast convergence,introduce the global sliding state factor into the non-singular fast terminal sliding mode surface,and introduce the adaptive law,design a global adaptive non-singular fast terminal sliding mode controller,thereby ensures the stability and global fast convergence of the system,the convergence time of the error variable is further shortened,the robustness of the system is improved,and the chattering phenomenon is suppressed.Then,for speed sensorless control technology for induction motor,a new non-singular fast terminal sliding mode observer with a similar approach law is designed.The sliding mode chattering problem is alleviated,the system convergence speed is accelerated,and the accuracy of the observer observation speed is improved.The simulation verifies the feasibility and superiority of the sliding mode observer.Finally,in order to further prove the effectiveness of the proposed method,an experimental platform of induction motor vector control system based on DSP(TMS320F28335)board is built,and the relevant program software is written and designed in the CCS3.3 development environment,therefore,the no-load and loading experiments of the motor are carried out.The experimental results verify the accuracy and superiority of the research method.