System and method for determining health indicators for impellers

A system comprising:

• a plurality of sensors configured to measure one or more characteristics of an impeller;
• and
• an impeller condition indicator device comprising:
• an input interface configured to receive input signals from the sensors, each of the input signals associated with at least one stage of the impeller and with two or more frequencies associated with operation of the impeller;
• a processor configured to identify a specific failure mode in the impeller using the input signals;
• and
• an output interface configured to provide an indicator identifying a health of the impeller;
• wherein the processor is configured to identify the specific failure mode by, for each of the input signals:
• determining a family of frequencies related to at least one of the two or more frequencies associated with operation of the impeller, the family of frequencies including a vane pass frequency and its harmonics;
• decomposing the input signal by performing a transform of the input signal and isolating components of the transformed input signal into selected frequency bands;
• reconstructing an impeller signal using portions of the decomposed input signal within the selected frequency bands associated with the family of frequencies;
• comparing the reconstructed impeller signal to a baseline signal;
• and
• categorizing the comparison based on failure mode rules including effects that the specific failure mode has on the two or more frequencies associated with operation of the impeller.

A method for identifying a health of an impeller corresponding to a specific failure mode of the impeller, the method comprising:

• receiving at one or more processing devices an input signal comprising at least one of vibration and speed infonnation corresponding to at least one stage of the impeller, the input signal associated with two or more frequencies associated with operation of the impeller;
• determining a family of frequencies corresponding to at least one of the two or more frequencies associated with operation of the impeller, the family of frequencies including a vane pass frequency and its harmonics;
• decomposing the input signal by performing a transform of the input signal and isolating components of the transformed input signal into selected frequency bands;
• reconstructing an impeller signal using portions of the decomposed input signal within the selected frequency bands associated with the family of frequencies;
• comparing the reconstructed impeller signal to a baseline signal;
• categorizing the comparison based on failure mode rules including effects that the specific failure mode has on the two or more frequencies associated with operation of the impeller;
• outputting an indicator identifying the health of the impeller;
• and
• in response to determining the reconstructed impeller signal differs from the baseline signal by a threshold amount, outputting an indicator identifying a fault.