METHOD FOR DIAGNOSING TECHNICAL STATE OF ELECTRIC CENTRIFUGAL PUMP BY ANALYSING CURRENT SIGNALS Russian patent published in 2025 - IPC F04D17/08 

FIELD: measuring.

SUBSTANCE: invention relates to measurement equipment, namely to diagnostics of technical state of centrifugal pump, and can be used for monitoring of current technical state of centrifugal pumps. Method of diagnosing the technical state of the pump by analysing current signals is characterized by the following: determining reference signals of current sensors installed on phase conductors of an electric motor of a serviceable pump, experimental signals of current sensors installed on phase conductors of electric motor of diagnosed pump are determined, performing their mathematical processing and comparing reference and experimental processing results; from arrays of received signals of consumed currents by method of non-overlapping window calculating by means of computer system average value and root-mean-square deviation by size of window k; calculating a first quartile, which includes signal sampling values not exceeding 25% of units of the set of signal values by window size k for first, second and third phase current signals; pairwise calculation of correlation coefficients between the calculated root-mean-square deviations of the current signals of the first, second and third phases by the size of the window k; pairwise calculation of correlation coefficients between the calculated first quartiles of the current signals of the first, second and third phases by the size of the window k; fixing the reference values of the calculated correlation coefficients for the previously fixed rotation frequencies of the shaft of the electric motor of the serviceable pump; for mathematical processing of current signals of a diagnosed electric centrifugal pump during operation, values of consumed currents of the electric motor of the diagnosed pump are measured at previously fixed frequencies of rotation of the shaft of the electric motor of a serviceable pump; from the arrays of the received signals of the consumed currents of the diagnosed electric centrifugal pump by the non-crossing window method, the root-mean-square deviation by the window size k is calculated using the computer system; calculating the first quartile, including the signal sampling values not exceeding 25 % of the set of signal values by the window size k for the current signals of the first, second and third phases of the diagnosed electric centrifugal pump; pairwise calculating the correlation coefficients between the calculated root-mean-square deviations of the current signals of the first, second and third phases of the diagnosed electric centrifugal pump by the size of the window k; pairwise calculation of correlation coefficients between the calculated first quartiles of the current signals of the first, second and third phases of the diagnosed electric centrifugal pump by the size of the window k; then comparing calculated values of correlation coefficients for serviceable electric centrifugal pump with calculated values of correlation coefficients for diagnosed electric centrifugal pump; if the values of correlation coefficients of the diagnosed and serviceable electric centrifugal pump differ by more than 7%, a conclusion is made on the presence of a defect in the diagnosed electric centrifugal pump.

EFFECT: improving reliability of diagnostics of technical condition of electric centrifugal pump by analysis of current signals during operation.

1 cl, 7 dwg