Abstract:In this paper, we establish the motion model of the two-stage vibration isolation system, then derive and analyze the closed-loop transfer function of the system. The analysis results show that when PID feedback is adopted, the equivalent damping coefficient of the system can be adjusted more conveniently than the PD feedback used in the current ultra-long spring(superspring). The equivalent natural period of the system is mainly affected by the feedback proportional coefficient kp; the larger the kp is, the longer the equivalent natural period, and the system will have better vibration isolation performance. After kp is selected, the integral coefficient ki together with the differential coefficient kd will affect the damping of the system, and ki is dominant, which determines the stability of the system. The accuracy of the closed-loop transfer function analysis results are verified by simulation, which show that the vibration isolation effect of the system can reach -70 dB at 1 Hz.
HU Yuanwang,ZOU Tong,ZHANG Li et al. Analysis and Simulation of Two-Stage Ultra-Low Frequency VibrationIsolation System Based on PID Feedback[J]. jgg, 2020, 40(9): 976-980.