Online soft measurement method for equivalent volume elastic modulus of flowing fluid of hydraulic pipeline

The invention discloses an online soft measurement method for equivalent volume elastic modulus of flowing fluid of a hydraulic pipeline. A pair of pressure transmitters is arranged in a hydraulic pipeline; the change of the fluid pressure due to the pressure pulsation of the plunger pump is synchronously recorded; after a synchronous pressure signal of a measuring point position in a pipeline isobtained, a zero-phase low-pass filter is used for preprocessing the signal; finally, cross-correlation operation is conducted on the preprocessed pressure signals, the transmission time of the pressure pulsation of the power source between the pressure measuring points is obtained, and the equivalent volume elastic modulus of fluid between the pressure measuring points of the hydraulic pipeline is obtained by further calculating the transmission time of pressure waves between the measuring points. Normal operation of a hydraulic system is not disturbed, online soft measurement of the equivalent volume elastic modulus