Research On Rotating Phase Control Of Eccentric Rotors In Vibrating Machinery

Vibration machinery is a kind of machinery to complete various industrial tasks according to the principle of vibration,which is widely used in the corresponding fields of steel,metallurgy,coal,mining,construction and so on.Vibrating machinery is inevitable in industrial production.At present,with the continuous development of modern industry and agriculture,vibration machinery to intelligent,high precision,high efficiency and other directions of development,so the application of vibration synchronization technology and electromechanical coupling principle,research and analysis of vibration synchronization system dynamics characteristics,to meet the actual needs of engineering,is the current research focus in this field.Self-synchronizing vibration machinery based on vibration synchronization theory has been widely used in engineering field.However,due to the limitation of its inherent characteristics,the process effect is not good,can not achieve the ideal trajectory and desired amplitude and other problems,so the control synchronization technology to replace vibration synchronization technology to solve the problem of its limitations.At present,most scholars study the vibration synchronization of two-machine or multi-machine drive vibration system under ultra-far resonance,and there is little research on near resonance.Considering the advantages of near resonance system,it is necessary to study it.However,Sommerfeld effect may occur when working in the near resonance region,because almost all engineering prime movers are non-ideal prime movers during the study of vibration system.Under the above background,in order to solve the existing engineering problems of self-synchronous vibration machinery as the starting point,"Research on the rotation phase control of eccentric rotor in vibration machinery" as the topic,three typical dynamic models as the research object.Based on the theory of vibration synchronization,the control synchronization theory is proposed,and the zero phase difference synchronization of the system is realized by using the control synchronization technology,so as to satisfy the motion trajectory and amplitude required by the engineering.The dynamic characteristics of the vibration system and Sommerfeld effect in the near resonance region are studied by means of electromechanical coupling theory.The main research contents of this thesis are as follows:(1)The introduction part summarizes the development and research methods of vibration synchronization theory in this field,introduces the research methods of control synchronization theory in view of the limitations of vibration synchronization,and briefly introduces the control strategy and control algorithm in vibrating machinery.(2)The control synchronization technology is introduced into the far resonance vibration system,the electromechanical coupling model of the two-machine vibration system is established,the synchronization condition and the synchronization stability condition are derived by using the small parameter average method,and the fuzzy PID controller and the master-slave control structure are innovatively designed.Finally,Matlab/Simulink simulation is used to verify the effectiveness and robustness of the designed controller,so as to solve the problem of poor process effect of vibrating screen.(3)For the near resonance vibration system with two eccentric rotors,the system dynamics differential equation is obtained according to Lagrange equation,and then the concept of "capture moment" is given based on the dynamics theory.Then the frequency capture equation of vibration system is created to obtain the nonlinear equation of phase difference and frequency capture of the eccentric rotor.Finally,the accuracy of the theoretical derivation is proved by computer numerical simulation.(4)The non-ideal vibration system driven by induction motor is studied.Firstly,the dynamics model of the system is established,and then the stability of the solution and solution in steady state is obtained according to the analytical method and the perturbation method.Then,the influence of system parameters on Sommerfeld effect is analyzed.Finally,the correctness of the theoretical method is verified by simulation.