Research On The Analysis And Effect Evaluation Of Frequency-averaged Power Flow In Complex Vibration Isolation System

Vibration power flow, through the efforts of many people, the power flow method had been confirmed its status in the field of system or structure dynamic analysis theory. In this text, about the wide frequency band excitation, we use the frequency-averaged power flow which was put forward by R. J. Pinnington as a measurement, bring the P_ave as the description of the system dynamic characteristic to discuss the problem of optimum design about wild frequency band excitation vibration isolation system. This project is supported by doctor foundation of Shandong.The second part of the test, based on a model for the complex flexible passive vibration isolation system, import the active control, establishs a general model for passive and active control, and use the actuator impedance to educe the calculate method of the power flow of the passive and active flexible couple vibration isolation system. This model provides a theoretical basis for the analysis and control of complex coupling flexible system.On this basis, mainly study on the infection which the each parameter of the passive and floating raft vibration isolation system to frequency-averaged power flow in the text. The result show that a secondary optimum asymmetry arrangement of the system exist besides the optimum symmetrical arrangement, and also an optimum mounts distance design can make the frequency-averaged power flow into the foundation lowest.However, to the active vibration isolation system, we must set up an integrative effectiveness estimation which considers synchronously the enforce outfit energy consume and vibration isolation efficiency. From the viewpoint of the insertion loss to estimates the effect of the active vibration isolation. Assume P_o is the power flow before the active actuator insert, and P_o' is the power flow after the active actuator insert, so the availability condition for active control is Po/P_o' > 1, and the ratio is more big, the active control is more effective. The result show that in lower band, under the different feedback control, can effectively control the vibration, the active vibration isolation more effective than passive vibration isolation, but under the control of the relative displacement, velocity and acceleration feedback, in higher band, after fixing the active actuator, augment the energy consume, reduce the isolation. In order to seek the optimum value of the lower consume and effectively control, we need to amend the parameter of feedback control.