The invention discloses a subsystem fluctuation
signal analysis method based on
causal analysis, and the method comprises the steps: carrying out the
decomposition of a multi-dimensional
signal through employing an MEMD method, obtaining the Imf of each layer of all signals, carrying out the grouping of each layer Imf of each
signal based on a
normalized correlation coefficient, correcting the
group based on a sparse index, and carrying out the analysis of a fluctuation signal. A
harmonic detection method is adopted to search for fundamental
waves and
harmonic waves Imf which are in an integral
multiple relation in the groups, signals with the fundamental
waves and the
harmonic waves at the same time are selected to serve as the result of grouping harmonic detection
feature selection, denoising and periodic term removing
processing is conducted on fluctuation signals subjected to
feature selection, the remaining part is reconstructed, and corresponding target sub-signals are obtained; and calculating cross mapping indexes of the reconstructed sub-signal pairs under different
time lag by using an extended CCM method, judging whether to converge according to a convergence threshold, obtaining a causal relationship of each signal pair, further obtaining a fluctuation propagation path, and positioning a fluctuation source. According to the method, the fluctuation propagation path in the
industrial control system can be quickly and accurately diagnosed, and the fluctuation source can be positioned.