The Research of Hydraulic System Anti-Vibration and Noise Reduction

Abstract

In this paper, the hazards of hydraulic pipeline system vibration and noise were introduced, the causes of vibration and noise of hydraulic pump circuit were analyzed and its frequency components were discussed. A wave filter of structure resonator based on Fluid-structure coupling vibration is designed and manufactured according to the principle of gas muffler. The differential equation of rectangular plate transverse free vibration characteristics was established, the coupling vibration resonance frequency of filter structure vibration body was obtained about 218Hz by solving differential equation according to the Rayleigh - Ritz method. The hydraulic pump flow pulsation frequency was adjusted respectively 215.55 Hz and 197.4 Hz through frequency conversion motor adjustment, and then comparative experiments were tested on the hydraulic system pressure fluctuation test experimental platform. Experiments show that, when the inherent resonance frequency of filter structural vibration body was approached the hydraulic system frequency, system pulse energy would be effectively attenuated, system pressure fluctuations would be greatly reduced and pulse rate was dropped from 3.65％to 0.28％. The attenuation of the effects of pressure pulsations was validated through experimental research, but also its defects that the filter has frequency selectivity and band narrow were founded The later research direction was put forward and new technology for hydraulic system vibration control was provided.

Optimized indirect adaptive robust control for a class of uncertain nonlinear systems with time‐varying parameters

“…and D ( t ) is the modeling error caused by flow pulsation described as the work of References 31 and 32.Example A second‐order system that can describe most electromechanical systems. The state equation can be formulated as $$$$ \left\{\begin{array}{c}\kern2.0em {\dot{x}}_1={x}_2\\ {}{\theta}_0(t){\dot{x}}_2={k}_vu-{\theta}_1(t){x}_2-{\theta}_2(t)\mathit{\operatorname{sign}}\left({x}_2\right)+{\theta}_3(t)+\tilde{d}(t)\\ {}\kern2.2em y={x}_1\end{array}\right.$$…”

“…where k i ∈ R q i ×q i is a positive-definite diagonal feedback gain matrix. Substituting (36) into (31), we can obtain the error dynamic equation:…”