FREQUENCY-DOMAIN IMPLEMENTATION OF FILTERED-X ALGORITHMS WITH ON-LINE SYSTEM IDENTIFICATION FOR VIBRATION CONTROL

用于振动控制的频域LMS自适应控制算法的实现

This paper describes the implementation of frequency-domain least mean squares (LMS) and Filtered-X algorithms and compares the performance of the frequencydomain adaptive control algorithm to a comparable timedomain controller. When the frequency-domain LMS step size is allowed to vary as a function of frequency,the frequency-domain algorithm exhibits a better vibration reduction than the time-domain algorithm for the weaker frequencies in the energy spectrum.

介绍了基于ＬＭＳ的频域自适应控制算法，并将其应用于振动控制问题。首先，借助于离散付里叶交换（ＤＦＴ），推导了时域分块ＬＭＳ算法在频域的精确实现，强调这一实现的前提是采取“补零”的措施；其次，指出了频域ＬＭＳ算法的重要性质，即算法步长的随频率可变性，并给出了它们的求取考虑，最后，通过与相应的时域算法比较，表明频域自适应算法在进行多频谐振动的主动减振时，其效果明显优于时域算法。因此，该控制方法尤其适用于由转子动力学引起的振动主动控制问题。