Time Delay Compensation Strategy Of Magnetorheological Damper

Magnetorheological dampers are often used as intelligent components for intelligent vibration control due to their simple structure,adjustable damping force and low energy consumption.The magnetorheological damper intelligent control structure system has a good effect on resisting the damage of buildings caused by earthquake.However,due to the time lag of structural control,the damping effect of the structural control system cannot meet the ideal requirements.So reducing the influence of time lag plays an important in improving the damping effect.This paper is based on solving the time-delay problem of magnetorheological damper.The main research contents and results are as follows:(1)The performance test of magnetorheological damper is carried out.The mechanical properties of the damper are tested by sine wave and triangular wave displacement loading.The test shows that the output of the magnetorheological damper has a certain adjustable range and good energy consumption.There is a hysteresis nonlinear relationship between damping force and velocity.The hysteretic behavior of the damper recovery force model needs to be considered.(2)Based on the experimental results of different speed triangular wave excitation and magnetorheological damper under different currents,it is proposed to use the threesegment linear inverse model as the current value required for the feedforward estimation of the expected force,which is simple and convenient,and the estimation deviation is small;The experimental hysteresis curve and least squares principle are used to identify the improved Bouc-Wen model parameters with elastic and viscous behavior.The results show that the improved Bouc-Wen model with viscous behavior is better.(3)The feedforward-feedback joint control method is combined with the reverse current drive technology to reduce the influence of time lag,improve the dynamic response performance of the magnetorheological damper and the tracking effect on the expected force.The influence of feedforward-feedback combined control strategy and negative feedback control strategy on the dynamic response speed of the damper is analyzed by simulink simulation.The results show that the feedforward-feedback joint control improves the response speed by about 40%,and the reverse current drive technology can also be significantly reduced.The response time of the falling segment accelerates the demagnetization process.