The Optimal Controller Design For Active Vibration Isolation System

Active vibration isolation technique is a bright spot in the field of vibration isolation, which is also the outcome of human beings high demands for production and life. Active control technique has been an important novel vibration control method because of potential advantage of effective result and good adaptability, which may be used in aerospace, civil engineering, high speed vehicle isolation and others machine equipment vibration control. And the design of the controller is the key of the active vibration isolation technique. So, the study of the control strategy is of great theoretical value and practical significance.The idea of the active vibration isolation is to bring in the secondary path, and make the output of the secondary path and primary path equal under the additional power outside and proper control action, through which the vibration is reduced. In this paper, the optimization design of controller for the active vibration isolation system was researched by the way of feedforward and feedback control the first time. In the way of feedforward control, the optimization controller was designed under unconstrained and constrained based on the self adaptive algorithm of FXLMS. According to the limitations of the feedforward optimization control, a method based on iterative feedback tuning had been proposed. This method took the mean square value of residual force as target function, and designs the controller order based on the system model and actual demand. The trust region method was used for the controller parameters adjustment. Finally, a fixed lower order controller was obtained.According to the active vibration isolation system based on magnetictive actuator, two optimization methods were used for controller design. In the way of feedback control, the controller was divided into the fixed part and variable part. The fixed part was designed according the reserved performance and the variable part was adjusted in real-time, which could enhance the controllability and robustness of the system. The simulation results showed that both of the controllers had the ability to make the residual signals to zero, but the feedback method based on IFT technique had better effect in operating frequency range.