Numerical Simulation Of Vibration Reduction Of MR Damper Based On Semi-active Fuzzy Control

The seismic design of the building structure in the earthquake should not only be limited to the study of materials to improve the seismic performance,but also should be more active means of seismic design.However,the exact value of seismic excitation and the exact model of building structure cannot be obtained under the current scientific and technological means.Therefore,it is necessary to establish a control method which does not depend on the precise model to weaken the seismic response of the structure.Fuzzy control is an effective way to solve this problem,it can simulate the human brain thinking.It uses the basis of expert experience which is based on the input and output variables to control.Thus,fuzzy control does not require an accurate model of the controlled structure.The structure needs to combine the appropriate actuator,which can play a better control effect.In the earthquake,the damper as an actuator output control force to change the original structure of the stiffness and damping.It is an effective and relatively low cost of active seismic method.Magnetorheological fluid(MRF)has been developed for decades.It has been widely used by the Magneto-rheological fluid(MR)damper.MR damper has a fast response to low power consumption and continuously adjustable damping,which can be used in the field of vibration damping.However,the dynamic model of MR damper has a strong nonlinearity and it is a key technology to establish a suitable constitutive model of MR damper or an effective control strategy.The Semi-active control method adopted in this paper has the advantages of strong active control,low cost and simple setting.The combination of MR damper and fuzzy control can significantly reduce the seismic response of building structure.Overall,the main contents of this paper are as follows:1.The advantages and disadvantages of the Semi-active control and other control methods are analyzed.The principles of the constitutive relation selection of the MR damper.The key principles of the design of the fuzzy controller,the modeling and simulation of the example are described.2.In the MATLAB software Simulink platform,the design and preparation of the Bouc-Wen-based ordinary shear valve MR damper program are used in the fifth chapter of the paper.3.The fuzzy controller with trapezoidal membership function and Gaussian membership function is designed in the original interface(m file)and Simulink platform in MATLAB software respectively.The fuzzy damping rule based on semi-active control is compiled and used in the fifth chapter in this paper.From the controlled results,we can see that when the inner product is close and the different membership functions have little effects on the control effect of fuzzy control.4.In order to simulate the example,a state equation of a three-layer steel frame is established and input into the simulation model state space through Simulink platform.With the combination of the different fuzzy controllers and the stimulation by the natural seismic wave excitation,the Wilson-? time history analysis is compared with the control structure of the dynamic parameters of the peak and peak control rate.It is concluded that the Semi-active control system has good vibration-damping effects.The system can control the vibration response of the structure in real time efficiently.The system has certain engineering practice significance and reference value.