Harmonic modal detection and removal method for underdetermined delay hybrid system of rotating machinery

The invention discloses a harmonic modal detection and removal method for an underdetermined delay hybrid system of a rotating machine. The method comprises the following steps: collecting vibration response acceleration signals of each measuring point in a running state of the rotating machine and forming a signal sequence; performing short-time Fourier transform on the signal sequence to obtain a time-frequency domain; based on an energy maximization method, calculating a full-channel frequency energy sum through a time-frequency domain, and detecting a peak value frequency point; calculating cosine distances between the peak frequency point and other frequency points, and constructing a binary system time frequency mask to estimate a short-time frequency spectrum of each source signal; the short-time frequency spectrum of each source signal is subjected to inverse transformation of short-time Fourier transform, each source signal is recovered, and the boundary effect is eliminated through a filling line; p