摘要
该文研究具有不同位移和速度反馈时滞的单自由度线性系统辩识问题。分析了任意时滞条件下系统频响函数出现等值的条件 ,指出若对系统施加频率为 ω的简谐激励 ,则通过系统响应辨识出的时滞可能与系统的真正时滞相差 2 pπ/ ω,其中 p为正整数。对短时滞的可辨识性进行了分析 ,给出了若干可辨识条件。通过系统模态参数关于时滞的灵敏度 。
The identifiability problem is addressed in this paper for two time delays in the displacement and velocity feedback paths respectively of a linear system of single degree of freedom. The condition is derived first for the case when two frequency response functions with different time delays are equal at some frequencies. Thus, it is pointed out that if the system is subject to a harmonic input of frequency ω the identified time delays may be deviated from the real values by 2pπ/ω, where p is a positive integer. Afterwards, the identifiability of short time delays is analyzed and some identifiability conditions are given. Finally, the sensitivity of modal parameters of the closed-loop system with respect to the time delays are derived and the delay identification from the experimental modal parameters is described.
出处
《振动工程学报》
EI
CSCD
北大核心
2001年第2期161-165,共5页
Journal of Vibration Engineering
基金
国家杰出青年科学基金资助项目 (5 96 2 5 5 11)
国家自然科学基金资助项目 (19972 0 2 5 )
