Self-adaptive amplitude-phase control method for variable-step-size hydraulic vibration table

Abstract

The invention discloses an self-adaptive amplitude-phase control method for a variable-step-size hydraulic vibration table, which is used for improving the tracking precision of sine response signalsof all frequency points in a hydraulic vibration table test. According to the method, a self-correcting network composed of a sinusoidal signal generator and a self-adaptive filter is designed to compensate an input expected signal of a hydraulic vibration table control system, and the weight of the correcting network is updated through an improved variable step size LMS algorithm according to thecurrent moment error; in each control cycle, the self-correcting network performs subtraction on a current input expected signal and a feedback real-time response signal to obtain a current moment error; the weight of the self-correcting network is updated by utilizing the improved variable step size LMS algorithm according to the error; an output signal of the self-correcting network is used asan actual input signal of the hydraulic vibration table control system, so that the error of a system response signal is reduced, the response error approaches 0 after final convergence; and the vibration table can reproduce sine expected waveform signals input at each frequency point with high precision through the online adjustment method.

Description

technical field [0001] The invention belongs to the technical field of self-adaptive control, and in particular relates to a control method for improving the response accuracy of a hydraulic vibration table's sinusoidal waveform. Background technique [0002] The hydraulic vibration table has a wide operating frequency, large output thrust, and strong load capacity. It plays an important role in vibration tests. It is often used in fatigue vibration tests of various parts in the automotive industry, anti-vibration tests of building structures in civil engineering, and ships, Anti-vibration, vibration reduction, and vibration isolation tests for aerospace products. The hydraulic vibration table has a large hydraulic spring stiffness, small component inertia, and high hydraulic natural frequency, which makes the control system excellent in speed and response. It can be controlled by pole configuration and other control methods. Theoretically, the system can reproduce the input...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to provide a variable step size hydraulic vibration table adaptive amplitude and phase control method, which overcomes the problem that the traditional compensation control method of hydraulic vibration table has complicated parameter setting and is difficult to ensure real-time performance. The variable step size adaptive amplitude and phase control method can Running online during the control process, it can adaptively adjust the amplitude and phase of the input sinusoidal expected signal, thereby eliminating the amplitude attenuation and phase lag in the system response signal, so that the response signal can reproduce the input sinusoidal expectation of any frequency with high precision Signal

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