Delay Compensation Theory Research And Simulation Of Cable Active And Semi-Active Control With Time Delay Using Giant Magnetostrictive Actuator

Cable of cable-stayed bridge has a light weight, large flexibility, small damp and low natural frequency, which leads to produce various kinds of harmful vibration easily under external load. It is a kind of feasible method for cable vibration control using axial force provided. However, time delays are frequently encountered in the actual control system, which can diminish the performance and stability of the stay cable vibration control system, so the research of the time delay compensation theory on the cable structure is urgentThis dissertation has been supported by the National Key Basic Research Development Program(973 Program) of China(Grant No.2015CB057702) and the National Natural Science Foundation of China(Grant No.51378203).Focusing on cable-giant magnetostrictive actuator(GMA) control system, the mechanical model of GMA and the phase shifting method for time-delay compensation have been studied. The simulation analysis under the active control and semi-active control has been conducted. The main contents in this dissertation are as follows:(1) The basic concept and development status for cable vibration control are introduced. Advantages and disadvantages are analyzed on passive control,active control and semi-active control. Research status about the GMA actuator and time-delay compensation theory is also introduced. On the other hand, the main content in this paper is being presented.(2) GMA material performance, the structure of the homemade actuators were introduced. Mechanical performance experiment is carried out on GMA,The force of magnetic coupling relationship and the relationship between the displacement and force of the actuator were obtained by the experiment in this dissertation.(3) Small sag cable-GMA control system vibration model is established.Nonlinear vibration control problem of cable, The mean linearization and theinitial value linearization method were proposed, theoretical research and simulation analysis were carried out in this dissertation.(4) Time-delay compensation theory-phase shifting method was studied,Taking the single degree of freedom structure as an example, Influence quantity about the structure parameters and control parameters on phase shift method of time-delay compensation was obtained by simulation analysis in this dissertation.(5) Time delay compensation method of cable-GMA active control system was put forward, solving state motion of cable-GMA active control system using the linear optimal control algorithm(LQR). time delay compensation effect under free vibration and random vibration was obtained by simulation analysis,the simulation results show phase shift method can achieve good effect of time-delay compensation in above system, which is close to the vibration reduction rate without time delay optimal control.(6) Time delay compensation method of cable-GMA semi-active control system was put forward, solving state motion of cable-GMA semi-active control system. time delay compensation effect under the free vibration and random vibration was obtained by simulation analysis, the simulation results show phase shift method can achieve good effect of time-delay compensation in above system, which is close to the vibration reduction rate without time-delay.