摘要
针对航天产品目前主流多轴多激励随机振动环境试验的跟踪精度与控制稳定性不佳问题,对基于驱动谱耦合修正优化的算法进行了研究。根据多轴随机试验的振动控制原理与方法,提出用比例均方根迭代修正与系统频响特性更新均衡调控的方式提高试验控制系统驱动谱的跟踪精度,给出了相应的控制策略:根据参考谱中各控制谱的相干系数选择修正方法,相干系数小于0.95时,用更新系统频响矩阵的方法实现对驱动谱的修正;相干系数大于0.95时,用修正参考谱下三角矩阵的方法实现对驱动信号的修正,以此不断减小控制偏差。两点两激励的仿真控制结果表明:各控制点自谱控制效果好,满足工程要求。建立两振动台对细长条试件进行振动试验,结果表明控制响应自功率谱和动态范围均满足工程试验要求。
To solve the problem of poor tracking precision and control stability in multi exciter/multi axis random vibration test mainly for aerospace products,the algorithm of coupling correcting optimization based on driving spectrum was studied in this paper.According to the vibration control principle and method of multi axis random test,proportional root-mean-square iteration correction and frequency character updating were applied to improve tracking precision of the driving spectrum for the test control system.The control strategy was put forward.The correcting method is selected according to the coherent coefficients of each control spectrum in the reference spectrum.The frequency character updating is used to implement the correcting of driving spectrum when the coherent coefficient is smaller than 0.95.The lower triangular matrix is used to implement the correcting of the driving signal when the coherent coefficient is larger than 0.95.The control deviation will be decreasing by this way.The simulation results of two-point and two exciters test showed that control of the auto-spectrum for the two control points was good which met the engineering requirement.The test results of the slender body on the two vibration tables showed that the control response of the auto-spectrum and dynamic scope met the requirement of the engineering test.
出处
《上海航天》
CSCD
2017年第5期88-93,共6页
Aerospace Shanghai
基金
国防基础科研基金项目资助
关键词
多轴多激励
随机振动
均衡调控
跟踪精度
控制稳定性
驱动谱
耦合修正
相干系数
multi exciter/multi axis
random vibration
balanced regulation
tracking precision
control stability
driving spectrum
coupling correction
coherent coefficient
