Multi-phase power meter configured for monitoring generator battery voltage

• US 10,012,702 B2
• Filed: 12/19/2012
• Issued: 07/03/2018
• 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
• Primary Examiner(s): Muralidar, Richard V
• Application Number:
  US14/652,197
• Publication Number:
  US 20150331061A1
• Time in Patent Office: 2,022 Days
• Field of Search: 701 321, 701 329, 701 334, 701 337- 341, 701 99, 701101, 701113, 320134, 320136
• 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 having a first plurality of terminals electrically connected to the electrical outputs of the generator for receiving signals from the electrical outputs of the generator and a terminal electrically connected to the battery for receiving a signal from the battery, the monitoring system being configured to;

monitor electrical characteristics of power supplied from the electrical outputs of the generator using the first plurality of terminals of the electrical meter,

capture a profile of voltage across terminals of the battery during a supply of electrical energy from the battery to the starter motor through the terminal of the electrical meter electrically connected to the battery,

define one or more regions of a reference voltage profile, each of the one or more regions having a duration and a magnitude of voltage change,

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

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

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

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 further 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.

10. The system of claim 1, wherein the monitoring system is further 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 predefined amount.

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.

11. 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;

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,

generating one or more mathematical equations describing the reference voltage profile in the one or more regions,

defining statistical process control limits about the one or more mathematical equations,

monitoring characteristics of electrical power supplied by electrical outlets of the generator with an electrical meter using a first plurality of terminals of the electrical meter electrically connected to the electrical outlets of the generator;

capturing a battery voltage profile during a generator start operation with the electrical meter through a terminal of the electrical meter electrically connected to the battery;

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

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

12. The method of claim 11, further comprising issuing a 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.

13. The method of claim 11, 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.

14. The method of claim 13, further comprising issuing a 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.

15. The method of claim 13, further comprising issuing a 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.

16. The method of claim 13, further comprising issuing a 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.

17. The method of any claim 11, 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.

18. The method of claim 11, 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.