抗震混合试验中预测-校正加载控制方法研究

Predictor-corrector Loading Control Method in Seismic Hybrid Simulation

为使抗震混合试验中电液伺服作动器加载与有限元分析同步进行,国外研究者将预测-校正加载控制方法引入该试验中,但在高频率模态或远离区间左端点处作动器命令信号的精确性不高。为提高该技术的精确性,本文对采样时间间隔内加速度变化规律的假设,以当前步的位移和速度为初始值,对加速度进行二次积分且以五阶精度的一、二阶导数作为速度、加速度,得到预测-校正表达式(PCVA-β),运用绝对误差限判断各种算法的精确性。使用Matlab/Simulink编程仿真模拟,结果表明:在较高阶频率且远离区间左端点处,这种方法不仅精确性较好且作动器能够连续平稳的运行。

It is important to synchronize the finite element analysis and the servo-hydraulic actuator loading,the predictor-corrector loading control method has been introduced into the seismic hybrid simulation,but the accuracy of the actuator command signals deteriorates for the high-frequency modes or the far left endpoint of interval. In order to improve the precision of such techniques,an acceleration of the sampling time step is assumed in the paper,integrating the acceleration and using the displacement and velocity at the beginning of the time step as initial conditions,the predictor-corrector expression（ PCVA-β） is obtained,and using the absolute error limits as the criteria of accuracy. The programming and simulation of Matlab /Simulink are conducted,the results show that this method not only has a good accuracy but also can make the actuator run continuously and smoothly.