Research On Semi-active Fuzzy Control Of Structure With MR Damper

Semi-active control for structural vibration with MR (Magneto-Rheological) dampers has become a hotspot problem of structural vibration control study. Traditional control arithmetic of structural vibration control usually need precise dynamical model. While mathematical model of actual structure is hardly ensured. Semi-active control using MR damper based on fuzzy control technique which is independent of computational model is studied deeply in this dissertation.A Simulink model of the MR damper called SD-1000 which was produced by LORD Company of USA is established for simulation of semi-active vibration control. This Simulink model of MR damper is convenient for transplant and has good practicability. The intelligent method such as improved BP network and ANFIS are used to identify the model and inverse model of the MR damper, which get a good effect.A kind of semi-active control strategy called Sigmoid clipped-optimal is brought forward based on LQR optimal control arithmetic and Instantaneous optimal control arithmetic. The control voltage is adjusted correspondingly according to difference between the control force and the damper force in the strategy, which avoids the"flicker"caused by the on-off control strategy and exert dissipation idiosyncrasy of the MR damper better.According to the principle of making the structure return to the balance position as soon as possible, fuzzy control rules are gained from the interrelation of displacement and velocity based on vibration theory and fuzzy control force is deduced by fuzzy theory. The fuzzy control force can be performed by many kinds of actors, which is very universal for structural vibration control. Fuzzy semi-active control strategy which is clear and can substitute the traditional clipped-optimal semi-active controller is put forward to ascertain the input voltage of the MR damper. This fuzzy strategy can accommodate the control voltage with damper force and the fuzzy control force, making the damper run after the fuzzy control force rapidly and aiming to achieve fuzzy semi-active control. The simulation research indicates that the effect of the fuzzy semi-active control approaches LQR optimal control.Because fixed coefficient of fuzzy control may lead to blind section, variable universe parameter online adjust of adaptive fuzzy control is studied, and the flex-factor of parameter adaptive adjusting is designed. The flex-factor is applied to fuzzy semi-active control of velocity voltage and displacement voltage and good control impact is obtained.