Automatic pump protection system

• US 4,913,625 A
• Filed: 12/18/1987
• Issued: 04/03/1990
• Est. Priority Date: 12/18/1987
• Status: Expired due to Fees

• Current Assignee: Westinghouse Electric Company LLC (Brookfield Asset Management Incorporated)
• Original Assignee: Westinghouse Electric Company LLC (Brookfield Asset Management Incorporated)
• Inventors: Gerlowski, Thomas J.
• Primary Examiner(s): Freeh, William L.
• Application Number:
  US07/134,720
• Time in Patent Office: 837 Days
• Field of Search: 417/18, 417/19, 417/32, 417/43, 417/53, 413/17, 413/24
• US Class Current: 417/18
• CPC Class Codes: F04D 15/0227 Lack of liquid level being detected using a flow transducer
• CPC Class Codes: F04D 15/0236 Lack of liquid level being detected by analysing the parameters of the electric drive, e.g. current or power consumption
• CPC Class Codes: F04D 15/0281 responsive to a condition not otherwise provided for
• CPC Class Codes: F04D 29/669 especially adapted for liquid pumps F04D29/18 takes precedence

Abstract

An automatic pump protection system is comprised of a plurality of sensors for measuring process parameters indicative of a loss of pump suction or of pump motor failure. Analysis of the parameters is performed by a microprocessor in order to determine whether conditions leading to a loss of pump suction or pump motor failure are present. The microprocessor then automatically initiates pump protective action in response to the foregoing analysis by tripping the pump or by providing an alternate suction source.

Claims

1. A system for automatically protecting a pump, comprising:

means for measuring process parameters indicative of a loss of pump suction;

first means responsive to said means for measuring for determining whether conditions leading to vortex formation are present;

second means responsive to said first means for determining and said means for measuring for determining whether conditions leading to air entrainment are present; and

means for automatically initiating pump protective action in response to said second determination.

2. The system of claim 1 wherein said means for measuring said process parameters include means for measuring temperature, pressure, fluid flow rate and fluid level.

3. The system of claim 1 wherein said means for automatically initiating pump protective action include means for automatically tripping the pump.

4. The system of claim 1 wherein said means for automatically initiating pump protective action include means for providing an alternate suction source.

5. The system of claim 1 further comprising means for measuring pump motor vibration level and means for determining whether said vibration level is indicative of a pump failure condition.

6. The system of claim 1 further comprising means for measuring pump motor electrical current level and means for determining whether said current level is indicative of a pump failure condition.

7. The system of claim 1 further comprising means for measuring pump motor sound frequency/intensity and means for determining whether said frequency/intensity is indicative of a pump failure condition.

8. The system of claim 1 wherein said means for measuring said process parameters include means for measuring fluid level and pressure.

9. The system of claim 8 wherein said first means responsive to said means for measuring include means for determining whether the fluid level has dropped to a critical level.

10. The system of claim 1 wherein said means for measuring said process parameters include means for determining isolation valve position.

11. The system of claim 10 further comprising means for determining whether the isolation valve is closed.

12. A residual heat removal system having automatic pump protection, comprising:

a pump;

a suction line connecting said pump to a suction source;

means for measuring suction line parameters indicative of a loss of pump suction;

first means responsive to said means for measuring for determining whether conditions leading to vortex formation are present;

second means responsive to said first means for determining and said means for measuring for determining whether conditions leading to air entrainment are present; and

means for automatically initiating pump protective action in response to said second determination.

13. A method for automatically protecting a pump, comprising the steps of:

measuring process parameters indicative of a loss of pump suction;

determining whether conditions leading to vortex formation are present in response to said parameters;

determining whether conditions leading to air entrainment are present in response to said parameters and said first determination; and

automatically initiating pump protective action in response to said second determination.

14. The method of claim 13 wherein the step of measuring said process parameters includes the step of measuring temperature, pressure, fluid flow rate and fluid level.

15. The method of claim 13 wherein the step of automatically initiating pump protective action includes the step of automatically tripping the pump.

16. The method of claim 13 wherein the step of automatically initiating pump protective action includes the step of providing an alternate suction source.