Design And Performance Of Electromagnetic Active Vibration Absorber

With the development of the power device towards miniaturization,lightweight and high speed,its vibration and noise problems become more and more prominent.The existence of vibration and noise not only affects the efficiency of the power device but also affects its working life.The traditional passive damping method can not control the vibration in the whole frequency because it can not cope with the change of the external excitation frequency,In order to solve the shortcomings of the passive damping method,the active control method has become the hotspot of the current damping research.Active vibration absorber is the implementation of active control method,its performance and control methods have a direct impact on the vibration.This paper mainly focuses on the structural design,active control algorithm and characteristic test of electromagnetic actuator in electromagnetic active vibration absorber.Firstly,according to the working principle of the active absorber,the vibration system of electromagnetic active absorber is simplified as a single degree of freedom system with damping and forced vibration,and the corresponding dynamic model is established.It is concluded from MATLAB simulation that when the frequency ratio is much larger than 1,the force required by the vibration system is equal to the electromagnetic force generated by the electromagnetic actuator.The material of each component of the electromagnetic actuator is determined.The influence of permanent magnet thickness and air gap size on the output of electromagnetic force was analyzed by electromagnetic field simulation analysis.The overall structure of electromagnetic actuator was determined,and the strength of moving part was analyzed by finite element method.Secondly,the principle of parameter tuning of PID control algorithm is studied,and the influence of acceleration error and error rate on parameter setting is analyzed.Through the analysis of the system dynamics model,the transfer function of the system is obtained.Taking the acceleration level of the controlled system as the control target,a two-input three-output fuzzy controller is designed and the fuzzy-PID control is designed in combination with PID control.And the fuzzy-PID control is simulated by MATLAB/Simulink.The results show that under the control of fuzzy-PID,the overshoot of the system is 0.3mm,the adjustment time is 80 ms,the rise time is 20 ms.Finally,the electromagnetic actuator study were tested,the results show that the stiffness of the spring is 54N/mm,meeting the original design requirements.The dynamic force test of the electromagnetic actuator was completed,and the relationship between the force and the current frequency and voltage frequency was verified.To complete the assembly of the test bench,combined with the control algorithm.The results show that the electromagnetic vibration absorber can reduce the vibration level by 21.1d B on the fuzzy-PID control strategy.