Research on the Control Strategy of Hydraulic Shaking Table Based on the Structural Flexibility

Abstract

The frequency response characteristics of the hydraulic shaking table show the same as that of a two degree of freedom (DOF) resonance system due to the structural flexibility of the hydraulic shaking table. The hydraulic shaking system induces an anti-resonant peak during the working frequency band, which substantially reduces band width of the shaking table. The frequency response influence factor like mass, stiffness, and damping of the reaction wall are studied in this paper. The feed-forward control strategy is proposed in shaking system, which eliminates the effect of zero points at the anti-resonant peak and poles nearly the imaginary axis, broadens the bandwidth, and improves the control precision of the system. The notch filter is used to reduce the magnitude of resonant peak at the nature frequency of servo valve. The experimental results show that the proposed algorithm properly compensates the effect of structural flexibility and improves the bandwidth of the shaking system. INDEX TERMS Hydraulic shaking table, structural flexibility, resonance system, feed-forward control, notch filter.

Recent Progress on Control Techniques of Shaking Table and Array Systems in China: An Overview

“…However, the research algorithm only compensates for PID control, and the simulation waveform is sine wave, zero phase difference feedforward three-parameter compensation technology and seismic wave simulation research needs further development. In [32] the influence of the flexibility of the seismic test structure is considered and the feed-forward control strategy is applied to the electro-hydraulic seismic shaking table: using feed-forward control to compensate the zero point of the system to suppress the anti-resonance peak generated by the flexible foundation and put the pole offset to the virtual axis to further expand the system bandwidth. Experimental results show that the algorithm compensates the influence of structural flexibility and improves the bandwidth of the vibration system.…”

Instability Condition Derivation for Hydraulic AGC System under Pressure Closed‐Loop Control

“…Mobayen [42] also constructed a controller, which is helpful for the stability and robustness of the system. According to structural flexibility, the control strategy of the hydraulic shaking table was researched by Zhang et al [43]. Lots of the above scholars have carried out many useful researches, which can provide theoretical direction for the further analysis on oscillation mechanism of rolling mill.…”

Disturbance observer‐based output feedback control of hydraulic servo system considering mismatched uncertainties and internal pressure dynamics stability

“…Hydraulic valve-controlled single-rod actuator (HVSA) systems have been widely employed in many industrial applications [3]. For instance, they are widely used in the vehicle suspension system [4,5], fields of excavator [6,7], shaking table [8][9][10], actuators system [2,11], and testing equipment [12,13]. In view of these facts, how to achieve high-performance servo control of hydraulic system has been of great interest in both academia and industry over the last decades.…”