Electrical ground isolation and secondary failure reduction detection and isolation

• US 20060181821A1
• Filed: 04/11/2006
• Published: 08/17/2006
• Est. Priority Date: 04/02/2002
• Status: Active Grant

• Current Assignee: GE Global Sourcing LLC (Westinghouse Air Brake Technologies Corporation)
• Original Assignee: General Electric Company
• Inventors: Worden, Bret Dwayne, McNally, Christopher Wade, Kumar, Ajith K.
• Granted Patent: US 7,256,974 B2
• Time in Patent Office: Days
• US Class Current: 361/42
• CPC Class Codes: H02H 3/16 responsive to fault current to earth, frame or mass with balanced or differential arrangement H02H3/26 ; monitoring earth connection H02H5/105

Abstract

A system for isolating electrical ground faults and secondary failures in an electrical system, the system comprising an AC ground isolation state machine for detecting and isolating an AC ground, a DC ground isolation state machine for detecting and isolating a DC ground, a component failure isolation state machine for detecting and isolating a change in a resistance, and a component failure early detection algorithm for determining a failure before using the state machines.

Claims

1. In an off road vehicle having a plurality of components that are part of an electrical system, a method for detecting an early failure in one or more components in the electrical system, said method comprising:

(a) providing a model of operational conditions;

(b) collecting actual operational conditions; and

(c) comparing said model of operational conditions with said actual operational conditions to determine when said failure occurs.

2. The method of claim 1 wherein said comparing step comprises comparing a component'"'"'s expected resistance to said component'"'"'s collected resistance.

3. The method of claim 1 where said comparing step comprises comparing a component'"'"'s expected voltage value to said component'"'"'s collected voltage value.

4. The method of claim 1 wherein the off road vehicle is at least one of a locomotive and an off highway vehicle.

5. In an off road vehicle having an electrical system with a plurality of components, a system for isolating a change in resistance in the electrical system, said system comprising:

(a) a first state where said system waits until a change in resistance is detected;

(b) a second state where said system transitions when a change in resistance is detected to isolate a suspected component; and

(c) a third state to verify said suspected component isolated is causing said change in resistance.

6. The system of claim 5 wherein said second state comprises:

(a) a first sub state to determine a number of said plurality of components in said system; and

(b) a second sub state to allow one component to be enabled while all other components are disabled to determine if said change in resistance is in said enabled component.

7. The system of claim 5 further comprising a third sub state to inform said system of a component suspected of causing said change in resistance and wherein said first sub state, said second sub state, or said third state can be combined into a single sub state.

8. The system of claim 6 wherein said second sub state further comprises:

(a) a first test sub state to determine whether said change in resistance is detected when a low voltage is applied to said suspected component; and

(b) a second test sub state to determine whether said change in resistance is detected when a high voltage is applied to said suspected component.

9. The system of claim 5 wherein said third state leaves said component causing said change in resistance disabled and enables other components in said system to confirm said ground is no longer detected.

10. The system of claim 5 wherein the off road vehicle is at least one of a locomotive and an off highway vehicle.

11. In an off road vehicle having an electrical system, a system for detecting an early failure in a component of the electrical system, said system comprising:

(a) a model of operational conditions specific to said component;

(b) a collection of actual operational conditions from said component; and

(c) a processor to compare said model of operational conditions with said collection of actual operational conditions to determine when said failure occurs.

12. The system of claim 11 wherein said processor compares said component'"'"'s expected resistance to said component'"'"'s collected resistance.

13. The system of claim 11 wherein said processor compares said component'"'"'s expected voltage value to said component'"'"'s collected voltage value.

14. The system of claim 11 wherein the off road vehicle is at least one of a locomotive and an off highway vehicle.

15. A system for isolating electrical ground faults and secondary failures in an off road vehicle propulsion system, said system comprising:

(a) an AC ground isolation state machine for isolating a traction motor or alternator when an AC ground is detected;

(b) a DC ground isolation state machine for isolating a grid box when a DC ground is detected;

(c) a dynamic braking grid failure isolation state machine for isolating a grid box when a change in resistance is detected; and

(d) a dynamic braking grid failure early detection algorithm for determining a failure before using said state machines.

16. The system of claim 15 further comprising a traction motor ground isolation per axle torque limit system connected to said AC ground isolation state machine.

17. The system of claim 15 further comprising a supplemental voltage functions system providing voltage average rates and alternator rectifier bias state information to said state machines and said early detection algorithm.

18. The system of claim 15 wherein said dynamic braking grid failure early detection algorithm comprises a model of operation conditions which are compared to actual operation conditions to determine a failure in said propulsion system.

19. The system of claim 15 wherein said algorithm compares a modeled speed of a blower to an actual speed of said blower.

20. The system of claim 15 wherein the off road vehicle is at least one of a locomotive and an off highway vehicle.