System and method for determining whether a charging wire is broken

• US 20060108987A1
• Filed: 11/25/2005
• Published: 05/25/2006
• Est. Priority Date: 11/25/2004
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Aoyama, Toru
• Granted Patent: US 7,235,953 B2
• Time in Patent Office: Days
• US Class Current: 322/28
• CPC Class Codes: G01R 31/006 on road vehicles, e.g. automobiles or trucks testing of ignition installations peculiar to internal combustion engines F02P17/00
• CPC Class Codes: G01R 31/54 Testing for continuity
• CPC Class Codes: G01R 31/58 Testing of lines, cables or conductors testing of electric windings G01R31/72
• CPC Class Codes: H02J 7/0047 with monitoring or indicating devices or circuits

Abstract

In a system, a generator is configured to charge a battery through a charging wire connecting therebetween. A first unit measures a voltage of the battery, and a second unit detects an operating rate of the generator. A third unit determines that the charging wire is broken when the measured battery voltage is lower than a predetermined threshold voltage and the detected operating rate of the generator is lower than a predetermined threshold value.

Claims

1. A method of determining whether a charging wire connecting between a battery and a generator is broken, in which the generator is configured to charge the battery through the charging wire, the method comprising:

measuring a voltage of the battery;

detecting an operating rate of the generator; and

determining that the charging wire is broken when the measured battery voltage is lower than a predetermined threshold voltage and the detected operating rate of the generator is lower than a predetermined threshold value.

2. A method according to claim 1, wherein the generator includes a conductivity control element and outputs a voltage created by magnetic fluxes, the magnetic fluxes being generated in the generator based on an exciting current, the exciting current being supplied to the generator through the control element such that the control element controls its conductivity with respect to the exciting current based on a plurality of command values, the plurality of command values including a first command value determining an upper limit of the operating rate, and wherein the predetermined threshold value is lower than the first command value.

3. A method according to claim 1, further comprising:

comparing the measured battery voltage with the threshold voltage; and

comparing the detected operating rate of the generator with the threshold value after the comparison of the battery voltage with the threshold voltage, wherein the determining step determines that the charging wire is broken based on the compared results of the comparing steps.

4. A method according to claim 2, further comprising interrupting the determining of the charging wire based on the first command value.

5. A method according to claim 2, wherein the operating rate is equivalent to the conductivity of the control element with respect to the exciting current.

6. A method according to claim 2, wherein the plurality of command values include a second command value used to determine the output voltage of the generator, the conductivity of the control element is controlled based on a voltage control signal composed of a train of pulses of high and low voltage levels at predetermined periods with a reference duty in each period, the reference duty being determined based on comparison of the second command value with the output voltage of the generator, and wherein the operating rate of the generator is equivalent to the reference duty of the voltage control signal.

7. A method of determining whether a charging wire connecting between a battery and a generator is broken, in which the generator is configured to charge the battery through the charging wire, the method comprising:

determining whether the battery is in discharge;

detecting an operating rate of the generator; and

determining that the charging wire is broken when it is determined that the battery is in discharge and the detected operating rate is within a predetermined range, the predetermined range being determined by a first upper limit threshold value and a lower limit threshold value.

8. A method according to claim 7, wherein the generator includes a conductivity control element and outputs a voltage created by magnetic fluxes, the magnetic fluxes being generated in the generator based on an exciting current, the exciting current being supplied to the generator through the control element such that the control element controls its conductivity with respect to the exciting current based on a plurality of command values.

9. A method according to claim 7, wherein the determining whether the battery is in discharge includes comparing a current of the battery with a predetermined threshold current value, and determining the battery is in discharge based on the compared result.

10. A method according to claim 8, wherein the plurality of command values include a first command value allowing the generator to change the output voltage thereof to be lower than the battery voltage, and a second command value determining the upper limit threshold value, the upper limit threshold value is lower than the second command value, and the lower limit threshold value is higher than an operating rate corresponding to the first command value.

11. A method according to claim 9, wherein the determining that the charging wire is broken includes:

comparing the detected operating rate with the upper and lower limit threshold values after the comparison of the current of the battery with the predetermined threshold current value; and

determining whether the detected operating rate is within the predetermined range based on the compared result.

12. A method according to claim 10, further comprising interrupting the determining of the charging wire based on the second command value.

13. A method according to claim 8, wherein the operating rate is equivalent to the conductivity of the control element with respect to the exciting current.

14. A method according to claim 8, wherein the plurality of command values include a third command value used to determine the output voltage of the generator, the conductivity of the control element is controlled based on a voltage control signal composed of a train of pulses of high and low voltage levels at predetermined periods with a reference duty in each period, the reference duty being determined based on comparison of the third command value with the output voltage of the generator, and wherein the operating rate of the generator is equivalent to the reference duty of the voltage control signal.

15. A system for determining whether a charging wire connecting between a battery and a generator is broken, in which the generator is configured to charge the battery through the charging wire, the system comprising:

a first unit configured to measure a voltage of the battery;

a second unit configured to detect an operating rate of the generator; and

a third unit configured to determine that the charging wire is broken when the measured battery voltage is lower than a predetermined threshold voltage and the detected operating rate of the generator is lower than a predetermined threshold value.

16. A system according to claim 15, wherein the generator includes a conductivity control element and outputs a voltage created by magnetic fluxes, the magnetic fluxes being generated in the generator based on an exciting current, the exciting current being supplied to the generator through the control element such that the control element controls its conductivity with respect to the exciting current based on a plurality of command values, the plurality of command values including a first command value determining an upper limit of the operating rate, and wherein the predetermined threshold value is lower than the first command value.

17. A system according to claim 16, wherein the plurality of command values include a second command value used to determine the output voltage of the generator, and an electrical load is directly connected to the generator without through the charging line, further comprising:

a fourth unit configured to change the second command value to a predetermined value for protecting the electrical load when the third unit determines that the charging wire is broken; and

a fifth unit configured to put out an alert when the third unit determines that the charging wire is broken.

18. A system according to claim 17, wherein the predetermined voltage is higher than an open-circuit voltage of the battery, and equal to or lower than a maximum permissible voltage of the electrical load directly connected to the generator.

19. A system according to claim 16, wherein the plurality of command values include a second command value used to determine the output voltage of the generator, the conductivity of the control element is controlled based on a voltage control signal composed of a train of pulses of high and low voltage levels at predetermined periods with a reference duty in each period, the reference duty being determined based on comparison of the second command value with the output voltage of the generator, and wherein the operating rate of the generator is equivalent to the reference duty of the voltage control signal.

20. A system for determining whether a charging wire connecting between a battery and a generator is broken, in which the generator is configured to charge the battery through the charging wire, the system comprising:

a first unit configured to determine whether the battery is in discharge;

a second unit configured to detect an operating rate of the generator; and

a third unit configured to determine that the charging wire is broken when it is determined that the battery is in discharge and the detected operating rate is within a predetermined range, the predetermined range being determined by an upper limit threshold value and a lower limit threshold value.

21. A system according to claim 20, where the generator includes a conductivity control element and outputs a voltage created by magnetic fluxes, the magnetic fluxes being generated in the generator based on an exciting current, the exciting current being supplied to the generator through the control element such that the control element controls its conductivity with respect to the exciting current based on a plurality of command values.

22. A system according to claim 20, wherein the first unit is configured to compare a current of the battery with a predetermined threshold current value, and to determine the battery is in discharge based on the compared result.

23. A system according to claim 20, wherein the plurality of command values include a first command value used to determine the output voltage of the generator, and an electrical load is directly connected to the generator without through the charging line, further comprising:

a fourth unit configured to change the first command value to a predetermined value for protecting the electrical load when the third unit determines that the charging wire is broken; and

a fifth unit configured to put out an alert when the third unit determines that the charging wire is broken.

24. A system according to claim 23, wherein the predetermined voltage is higher than an open-circuit voltage of the battery, and equal to or lower than a maximum permissible voltage of the electrical load directly connected to the generator.

25. A battery charging system comprising:

a battery;

a generator;

a charging wire connecting between the battery and the generator, the generator being configured to charge the battery through the charging wire;

a first unit configured to measure a voltage of the battery;

a second unit configured to detect an operating rate of the generator; and

a third unit configured to determine that the charging wire is broken when the measured battery voltage is lower than a predetermined threshold voltage and the detected operating rate of the generator is lower than a predetermined threshold value.

26. A battery charging system comprising:

a battery;

a generator;

a charging wire connecting between the battery and the generator, the generator being configured to charge the battery through the charging wire;

a first unit configured to determine whether the battery is in discharge;

a second unit configured to detect an operating rate of the generator; and

a third unit configured to determine that the charging wire is broken when it is determined that the battery is in discharge and the detected operating rate is within a predetermined range, the predetermined range being determined by an upper limit threshold value and a lower limit threshold value.