Method for controlling random vibration of electrohydraulic servo system

Abstract

The invention discloses a method for controlling the random vibration of an electrohydraulic servo system, which comprises the following steps: utilizing an acceleration power spectral density reference signal to design a filter III, filtering a white noise signal and taking the output of the filtration as an acceleration time-domain driving signal; utilizing a single-step prediction Kalman filter algorithm to online regulate the weights of a Kalman filter I and a Kalman filter II in real time and performing identification on a frequency response function of the electrohydraulic servo system and an impedance function of the Kalman filter I respectively; and constructing a filter IV based on the identification result of the impedance function of the Kalman filter II, filtering the acceleration time-domain driving signal and taking the output of the filtration as an acceleration input signal of the electrohydraulic servo system. The method for controlling the random vibration of the electrohydraulic servo system utilizes the filter III to filter the white noise signal to obtain the acceleration time-domain driving signal, which simplifies the process of generating the time-domain driving signal. The convergence property of the single-step prediction Kalman filter algorithm adopted in the invention ensures the convergence property of the real-time on-line iteration of power spectral density.

Description

technical field [0001] The invention relates to a vibration simulation experiment method in the mechanical field, in particular to a random vibration control method of an electro-hydraulic servo system. Background technique [0002] Vibration simulation is a kind of environmental simulation and simulation experiment, and it is widely used in defense industry fields such as aviation, aerospace, nuclear industry and civil industry sectors such as automobile and construction. The purpose of the vibration test is to assess the ability of the product to maintain its original performance under vibration excitation, that is, to study and test the structural reliability and operational reliability of the product under vibration conditions. From the perspective of experiment type, vibration simulation experiments can be divided into three types: random vibration, sinusoidal vibration and waveform reproduction. The vibration conditions of the environment are generally given in the fo...

AI Technical Summary

Problems solved by technology

Among them, when converting the power spectral density into a time-domain driving signal, four steps are required: Cholesky decomposition, frequency-domain randomization, inverse Fourier transform, and time-domain randomization. The calculation process is complex and requires special hardware equipment.

The essence of the existing algorithm is an off-line iterative algorithm. When the parameters of the electro-hydraulic servo system or the characteristics of the specimen change during the experiment, the convergence of the iterative algorithm cannot be guaranteed, and even the iteration diverges, resulting in the power spectral density output signal of the system and the power Compared with the spectral density reference signal, there is a large deviation, which greatly reduces the accuracy of power spectral density reproduction and affects the quantitative evaluation of the reliability of the tested product in a vibration environment

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