Pump system diagnosis

• US 6,721,683 B2
• Filed: 03/08/2002
• Issued: 04/13/2004
• Est. Priority Date: 03/08/2002
• Status: Expired due to Fees

• Current Assignee: Insightek, LLC
• Original Assignee: Insightek, LLC
• Inventors: Harris, Casey A., Templeton, Frederick E., Schibonski, Jeffrey A., Wheeler, Dal L.
• Primary Examiner(s): Hoff, Marc S.
• Assistant Examiner(s): SUAREZ, FELIX E
• Application Number:
  US10/093,665
• Publication Number:
  US 20030171895A1
• Time in Patent Office: 767 Days
• Field of Search: 702/51, 702/57, 702/58, 702/64, 702/65, 702/96, 702/98, 702/100, 702/104, 702/142, 702/183, 600/438, 417/53, 123/435, 310/168
• US Class Current: 702/183
• CPC Class Codes: G05B 23/0221 Preprocessing measurements, e.g. data collection rate adjustment; Standardization of measurements; Time series or signal analysis, e.g. frequency analysis or wavelets; Trustworthiness of measurements; Indexes therefor; Measurements using easily measured parameters to estimate parameters difficult to measure; Virtual sensor creation; De-noising; Sensor fusion; Unconventional preprocessing inherently present in specific fault detection methods like PCA-based methods
• CPC Class Codes: G05B 23/0227 Qualitative history assessment, whereby the type of data acted upon, e.g. waveforms, images or patterns, is not relevant, e.g. rule based assessment; if-then decisions

Abstract

A low cost method and system for diagnosing and reporting potential pump system failure. A method embodying the invention includes calculating amperage variables for the pump moter using a signal from an amp sensor measuring electrical current used by the pump. Design values for the pump are acquired and diagnostic values are calculated using one or more calculated amperage variables and one or more of the acquired design values. Using the diagnostic values, diagnostic parameters are then calculated. Each design parameter is then compared with a baseline value or pattern. Where the design parameter verifies beyond a set tolerence limit, an adverse diagnosis is reported.

Claims

1. A pump motor diagnosis method, comprising:

calculating amperage variables for a fixed speed cyclically controlled pump motor using a signal from an amp sensor measuring electrical current used by the pump, the amperage variables including an average stator amperage for the pump motor, a frequency of the stator amperage, a duration of the stator amperage, and a time duration between amperage cycles;

acquiring pump motor design values;

calculating diagnostic values using one or more calculated amperage variables and one or more of the acquired design values;

calculating diagnostic parameters using one or more calculated diagnostic values; and

performing a diagnostic evaluation comparing one or more diagnostic parameters with one or more baseline values or patterns.

2. The method of claim 1, wherein calculating diagnostic values comprises calculating a discharge flow produced by the pump motor.

3. The method of claim 2, wherein calculating diagnostic values comprises:

calculating slip speed of the pump motor;

calculating a speed of the pump motor;

calculating an intake flow; and

calculating the discharge flow produced by the pump motor using the calculated slip speed, motor speed, and intake flow.

4. The method of claim 1, wherein the individual discharge flow produced by more than one pump motor are each calculated proportionally during a pump cycle in which multiple pumps are running simultaneously.

5. The method of claim 1, wherein calculating diagnostic values comprises calculating a torque produced by the pump motor.

6. The method of claim 1, wherein calculating diagnostic values comprises calculating a voltage supplied to the pump motor.

7. The method of claim 1, wherein calculating diagnostic values comprises calculating power supplied to the pump motor.

8. The method of claim 1, wherein calculating diagnostic parameters comprises calculating the energy consumed by the pump motor over a predetermined period.

9. The method of claim 1, wherein calculating diagnostic parameters comprises calculating a volume pumped over a predetermined period.

10. The method of claim 1, wherein calculating diagnostic parameters comprises calculating an average torque produced by the pump motor over a predetermined period. A pump motor diagnosis method, comprising:

calculating amperage variables for a pump motor using a signal from an amp sensor measuring electrical current used by the pump;

acquiring pump motor design values;

calculating diagnostic values using one or more calculated amperage variables and one or more of the acquired design values;

calculating diagnostic parameters using one or more calculated diagnostic values;

performing a diagnostic evaluation comparing one or more diagnostic parameters with one or more baseline values or patterns; and

wherein the diagnostic parameters calculated are one or more parameters from a group of diagnostic parameters consisting of;

an average torque produced by the pump motor over a predetermined period;

a volume to energy ratio;

a torque to energy ratio;

a filtered, leading-edge average of pump cycle duration over a defined time period or pump cycle sample;

a filtered, leading-edge average of pump stator amperage over a defined time period or pump cycle sample;

a filtered, leading-edge average of wet well inflow over a defined time period or pump cycle sample;

a filtered, leading-edge average of individual pump volumetric throughput over a defined time period or pump cycle sample; and

a pump operational order.

11. The method of claim 1, further comprising calculating a baseline value by averaging a calculated diagnostic parameter over a period of time.

12. The method of claim 1, further comprising establishing a baseline pattern by recording a time series of expected values for a particular diagnostic parameter.

13. The method of claim 1, further comprising reporting an adverse diagnosis when a calculated a diagnostic parameter varies from a baseline value or pattern beyond a set tolerance limit.

14. A computer readable medium having instructions for:

calculating amperage variables for a fixed speed cyclically controlled pump motor using a signal from an amp sensor measuring electrical current used by the pump, the amperage variables including an average stator amperage for the pump motor, a frequency of the stator amperage, a duration of the stator amperage, and a time duration between amperage cycles;

acquiring pump motor design values;

calculating diagnostic values using one or more calculated amperage variables and one or more of the acquired design values;

calculating diagnostic parameters using one or more calculated diagnostic values; and

performing a diagnostic evaluation comparing one or more diagnostic parameters with one or more baseline values or patterns.

15. The medium of claim 14, wherein the instructions for calculating diagnostic values comprise instructions for calculating a discharge flow produced by the pump motor.

16. The medium of claim 15, wherein the instructions for calculating diagnostic values comprise instructions for:

calculating slip speed of the pump motor;

calculating a speed of the pump motor;

calculating an intake flow; and

calculating the discharge flow produced by the pump motor using the calculated slip speed, motor speed, and intake flow.

17. The medium of claim 14, wherein the instructions for calculating diagnostic parameters comprise the instructions for calculating the individual discharge flow produced by more than one pump motor proportionally during a pump cycle in which multiple pumps are running simultaneously.

18. The medium of claim 14, wherein the instructions for calculating diagnostic values comprise instructions for calculating a torque produced by the pump motor.

19. The medium of claim 14, wherein the instructions for calculating diagnostic values comprise instructions for calculating a voltage supplied to the pump motor.

20. The medium of claim 14, wherein the instructions for calculating diagnostic values comprise instructions for calculating power supplied to the pump motor.

21. The medium of claim 14, wherein the instructions for calculating diagnostic parameters comprise instructions for calculating the energy consumed by the pump motor over a predetermined period.

22. The medium of claim 14, wherein instructions for calculating diagnostic parameters comprise instructions for calculating a volume pumped over a predetermined period.

23. The medium of claim 14, wherein the instructions for calculating diagnostic parameters comprise instructions for calculating an average torque produced by the pump motor over a predetermined period. A computer readable medium having instructions for:

calculating amperage variables for a pump motor using a signal from an amp sensor measuring electrical current used by the pump motor;

acquiring pump motor design values;

calculating diagnostic values using one or more calculated amperage variables and one or more of the acquired design values;

calculating diagnostic parameters using one or more calculated diagnostic values;

performing a diagnostic evaluation comparing one or more diagnostic parameters with one or more baseline values or patterns; and

wherein the diagnostic parameters calculated are one or more parameters from a group of diagnostic parameters consisting of;

an average torque produced by the pump motor over a predetermined period;

a volume to energy ratio;

a torque to energy ratio;

a filtered, leading-edge average of pump cycle duration over a defined time period or pump cycle sample;

a filtered, leading-edge average of pump stator amperage over a defined time period or pump cycle sample;

a filtered, leading-edge average of wet well inflow over a defined time period or pump cycle sample;

a filtered, leading-edge average of individual pump volumetric throughput over a defined time period or pump cycle sample; and

a pump operational order.

24. The medium of claim 14, having further instructions for calculating a baseline value by averaging a calculated diagnostic parameter over a period of time.

25. The medium of claim 14, having further instruction for establishing a baseline pattern by recording a time series of expected values for a particular diagnostic parameter.

26. The medium of claim 14, further having instructions for reporting an adverse diagnosis when a calculated a diagnostic parameter varies from a baseline value or pattern beyond a set tolerance limit.