MULTI-PHASE POWER METER CONFIGURED FOR MONITORING GENERATOR BATTERY VOLTAGE

• US 20150331061A1
• Filed: 12/19/2012
• Published: 11/19/2015
• Est. Priority Date: 12/19/2012
• Status: Active Grant

• Current Assignee: Schneider Electric USA, Inc. (Schneider Electric SE)
• Original Assignee: Schneider Electric USA, Inc. (Schneider Electric SE)
• Inventors: Hirschbold, Markus F., Loewen, Daniel Neil
• Granted Patent: US 10,012,702 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01R 31/367 Software therefor, e.g. for battery testing using modelling or look-up tables
• CPC Class Codes: G01R 31/3835 involving only voltage measurements
• CPC Class Codes: G01R 31/392 Determining battery ageing or deterioration, e.g. state of health

Abstract

Disclosed herein are embodiments of systems and methods for determining the state of health of a generator battery set and its ability to supply generator starter motor with start-up energy by capturing a profile of voltage across terminals of the battery during a supply of electrical energy from the battery to the starter and comparing the captured voltage profile to a reference voltage profile to determine if a difference between the captured voltage profile and reference voltage profile exceeds an acceptable amount.

Claims

1. A system for determining the state of health of a generator battery and the ability of the battery to supply a generator starter motor with start-up energy, the system comprising:

a generator having a starter motor and electrical outputs;

a battery electrically coupled to the starter motor of the generator; and

a monitoring system including an electrical meter electrically coupled to the electrical outputs of the generator and to the battery, the monitoring system being configured to;

monitor electrical characteristics of power supplied from the electrical outputs of the generator,

capture a profile of voltage across terminals of the battery during a supply of electrical energy from the battery to the starter motor, and

compare the captured voltage profile to a reference voltage profile and determine if a difference between the captured voltage profile and reference voltage profile exceeds an acceptable amount.

2. The system of claim 1, further including an output configured to issue a warning responsive to the difference between the captured voltage profile and the reference voltage profile exceeding the acceptable amount.

3. The system of claim 1, wherein the monitoring system further includes a controller configured to provide a signal to the generator to start and to provide a signal to the electrical meter to begin measuring the voltage profile.

5. The system of claim 1, wherein the controller is further configured to generate a visual representation of the captured voltage profile compared to the reference voltage profile.

6. The system of claim 1, wherein the monitoring system is configured to generate the reference voltage profile from a previously captured battery voltage profile.

7. The system of claim 6, wherein the monitoring system is configured to generate the reference voltage profile from an aggregation of a plurality of previously captured battery voltage profiles.

8. The system of claim 7, wherein the monitoring system is configured to generate the reference voltage profile from an aggregation of a plurality of previously captured battery voltage profiles captured from over a moving window of time during which a predefined number of generator start operations were performed

9. The system of claim 1, wherein the monitoring system is configured to define one or more regions of the reference voltage profile, each of the one or more regions having a duration and a magnitude of voltage change.

10. The system of claim 9, wherein the monitoring system is configured to build a mathematical model describing the reference voltage profile in the one or more regions and issue a warning responsive to the captured battery voltage profile differing from the mathematical model in corresponding one or more of the one or more regions by more than a predetermined amount.

11. The system of claim 9, wherein the monitoring system is configured to compare one of a duration and a voltage change magnitude of at least one region of the captured voltage profile to that of a corresponding at least one region of the reference voltage profile and issue a warning responsive to a difference between the one of the duration and the voltage change magnitude of the at least one region of the captured voltage profile and that of a corresponding region of the reference voltage profile exceeding a redefined amount.

12. The system of claim 9, wherein the monitoring system is further configured to:

generate one or more mathematical equations describing the voltage profile in the one or more regions;

define statistical process control limits about the one or more mathematical equations; and

issue a warning responsive to data points in the captured battery profile violating a statistical process control rule relative to the statistical process control limits.

4. The system of clam 1, wherein the controller is further configured to cause the electrical meter to begin to capture the voltage profile with a pre-trigger capture delay prior to the beginning of a generator starting operation.

13. A method of determining the state of health of a generator battery and the ability of the battery to supply a generator starter motor with start-up energy, the method comprising:

building a reference voltage profile for generator starts;

monitoring characteristics of electrical power supplied by electrical outlets of the generator with an electrical meter;

capturing a battery voltage profile during a generator start operation with the electrical meter;

comparing the captured battery voltage profile to the reference voltage profile; and

issuing a warning responsive to one or more parameters of the captured battery profile differing from one or more parameters of the reference voltage profile by more than a predetermined amount.

14. The method of claim 13, wherein issuing the warning comprises issuing the warning responsive to a cumulative sum of values of differences between a plurality of measurements of the voltage of the captured battery profile and the voltage of the reference voltage profile at corresponding periods of time exceeding a predefined limit.

15. The method of claim 13, wherein building the reference voltage profile for generator starts comprises defining one or more regions of the reference voltage profile, each of the one or more regions having a duration and a magnitude of voltage change and wherein capturing the battery voltage profile comprises defining one or more regions in the captured battery voltage profile corresponding to the one or more regions defined in the reference voltage profile.

16. The method of claim 15, wherein issuing the warning comprises issuing the warning responsive to a standard deviation of a plurality of measurements of the voltage in one or more of the regions of the captured battery voltage profile exceeding a standard deviation of voltage in the reference voltage profile in corresponding one or more regions by more than a predefined amount.

17. The method of claim 15, wherein issuing the warning comprises issuing the warning responsive to one or more parameters of at least two of the regions of the captured voltage profile differing from one or more parameters of corresponding regions of the reference voltage profile by more than predetermined amounts.

18. The method of claim 15, wherein issuing the warning comprises issuing the warning responsive to one or more parameters of a region of the captured voltage profile differing from one or more parameters of a corresponding region of the reference voltage profile by more than predetermined amount for more than a predetermined amount of time.

19. The method of any claim 13, further comprising generating a plurality of reference voltage profiles corresponding to different levels of an environmental factor and comparing the captured voltage profile to a reference voltage profile selected from the plurality of voltage reference profiles responsive to a level of the environmental factor.

20. The method of claim 13, further comprising monitoring a steady-state voltage profile of the battery during a time other than during the generator start operation and issuing a warning responsive to the monitored steady-state voltage profile differing from a reference steady-state voltage profile by greater than a predefined amount.