High frequency battery charger and method of operating same

• US 20060001401A1
• Filed: 08/29/2005
• Published: 01/05/2006
• Est. Priority Date: 01/25/2002
• Status: Active Grant

• Current Assignee: Vector Products Incorporated (Stanley Black & Decker, Inc.)
• Original Assignee: Vector Products Incorporated (Stanley Black & Decker, Inc.)
• Inventors: Krieger, Michael, Randolph, Bruce, Vetitoe, Roy Scott
• Granted Patent: US 7,564,223 B2
• Time in Patent Office: Days
• US Class Current: 320/128
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/007 Regulation of charging or discharging current or voltage
• CPC Class Codes: H02J 7/342 The other DC source being a battery actively interacting with the first one, i.e. battery to battery charging with circuits for polarity protection H02J7/0034

Abstract

A high frequency charger includes a charge circuit for charging a depleted battery and a boost circuit for jump-starting a vehicle. Two separate high frequency transformers are provided for the charge and boost circuits. A selector switch selectively activates at least one of the charging circuit and the boost circuit.

Claims

1. A high frequency battery charger for charging a target battery, comprising:

a charging circuit including a high frequency transformer, a switch switching the high frequency transformer, a filter coupled to the high frequency transformer for passing a DC voltage signal and a controller providing a high frequency driving signal to the switch;

measuring circuitry for measuring at least one of a voltage or a current at the target battery; and

a microprocessor receiving the measured voltage or current and calculating diagnostics of the target battery based on at least one of the measured voltage or current.

2. The charger of claim 1, further comprising connectors coupled to the charging circuit and adapted to be connected to the target battery for providing the DC voltage signal to the target battery, the measuring circuitry being coupled to the connectors to measure at least one of the voltage or the current.

3. The charger of claim 1, wherein the diagnostics include at least one of an overtime fault, a shorted cell fault, a bad battery fault, or an open cell fault.

4. The charger of claim 1, wherein the microprocessor determines a charging time of the target battery.

5. The charger of claim 4, wherein the microprocessor detects the overtime fault in dependence on the charging current being greater than a predetermined current, the charging time being longer than a predetermined time, and the voltage of the battery being less than or equal to a predetermined voltage after the predetermined time.

6. The charger of claim 5, wherein the predetermined current is 2 amps, the predetermined time is 18 hours and the predetermined voltage is 12 volts.

7. The charger of claim 4, wherein the microprocessor detects the shorted cell battery fault in dependence on the battery voltage being less than or equal to a predetermined voltage after a predetermined time.

8. The charger of claim 7, wherein the predetermined time is 1 hour and the predetermined voltage is 11 volts.

9. The charger of claim 3, wherein the microprocessor detects the bad battery fault when no target battery voltage is measured.

10. The charger of claim 3, wherein the microprocessor detects the open cell battery fault in dependence on at least the charging current being less than a predetermined current after a predetermined time.

11. The charger of claim 1 further comprising:

means for coupling a resistance in parallel with the battery; and

means for correlating the measured voltage to a cold cranking amps (CCA) value.

12. The charger of claim 3, further comprising a display for displaying representations corresponding to the calculated diagnostics.

13. The charger of claim 12, wherein the representations include fault codes.

14. The charger of claim 1, wherein the microprocessor is programmed to:

provide a test current that is lower than a charging current from the battery charger to the target battery;

detect if the test current is present at the target battery;

indicate a fault if the test current is not detected at the target battery; and

increase the test current a predetermined amount; and

return to the detecting step if the test current is detected at the target battery.

24. The method of claim 14, further comprising:

coupling a resistance in parallel with the battery; and

correlating the measured voltage to a cold cranking amps (CCA) value.

15. A method of charging a target battery, comprising:

providing a charging circuit including a high frequency transformer for producing a DC output signal;

providing a high frequency driving signal to a switch which switches the high frequency transformer;

measuring at least one of a voltage or a current at the target battery; and

calculating diagnostics based on at least one of the measured voltage or current.

16. The method of claim 15, wherein the step of calculating diagnostics comprises detecting at least one of an overtime fault, a shorted cell fault, a bad battery fault, or an open cell fault.

17. The method of claim 16, including determining a charging time of the target battery.

18. The method of claim 17, including detecting the overtime fault in dependence on the charging current being greater than a predetermined current, the charging time being longer than a predetermined time, and the voltage of the target battery being less than or equal to a predetermined voltage after the predetermined time.

19. The method of claim 18, wherein the predetermined current is 2 amps, the predetermined time is 18 hours and the predetermined voltage is 12 volts.

20. The method of claim 17, including detecting the shorted cell battery fault in dependence on the target battery voltage being less than or equal to a predetermined voltage after a predetermined timer,

21. The method of claim 20, wherein the predetermined time is 1 hour and the predetermined voltage is 11 volts.

22. The method of claim 16, including detecting the bad battery fault when no target battery voltage is measured.

23. The method of claim 16, including detecting the open cell battery fault in dependence on at least the charging current being less than a predetermined current after a predetermined time.

25. The method of claim 16, further comprising indicating the output of said diagnostics.

26. The method of claim 16, including:

providing a test current that is lower than a charging current from the battery charger to the target battery;

detecting if the test current is present at the target battery;

indicating a fault if the test current is not detected at the target battery; and

increasing the test current a predetermined amount; and

returning to the detecting step if the test current is detected at the target battery.

27. The method of claim 26, further comprising providing a current lower than the test current to the target battery and returning to the detecting step if the test current is not detected at the target battery.

28. The method of claim 26, wherein the test current is increased according to a ramp function or a step function.

29. The method of claim 26, further comprising using pulse width modulation to control the current provided from the battery charger.

30. The method of claim 26, further comprising determining if the test current equals a selected current, and if so continuing charging at the selected current, otherwise returning to the detecting step.

31. The method of claim 16, further comprising turning the charger off after a fault is detected.

32. A high frequency charger, comprising:

high frequency transformer means;

a switch switching the high frequency transformer means at a frequency and producing a charging current for charging a battery;

means for testing for at least one fault; and

a display for displaying a representation of the fault.

34. The charger of claim 32, wherein the overtime fault is detected when the charging current is greater than a predetermined current, the battery has been charging longer than a predetermined amount of time, and the voltage of the battery is less than or equal to a predetermined voltage.

35. The charger of claim 34, wherein the predetermined current is about 2 amps, the predetermined time is about 18 hours, and the predetermined voltage is about 12 volts.

33. A high frequency charger for charging a battery, comprising:

a charge circuit including a high frequency transformer, a switching configuration to switch the high frequency transformer to produce a charging current to charge the battery, and a filter coupled to the high frequency transformer for passing a DC voltage signal;

means for measuring at least one of the charging current of the battery, an amount of time the battery has been charging, or a voltage of the battery; and

means for detecting at least one of an overtime fault, a shorted cell fault, a bad battery fault, or an open cell fault based on at least one of the charging current of the battery, an amount of time the battery has been charging, or a voltage of the battery.

36. The charger of claim 33, further comprising a display that visually indicates at least one of the faults.

37. The charger of claim 33, wherein the shorted cell battery fault is detected when after a predetermined amount of time the battery voltage is less than or equal to a predetermined voltage.

38. The charger claim 37, wherein the predetermined time is about 1 hour, and the predetermined voltage is about 11 volts.

39. The charger of claim 33, wherein the bad battery fault is detected when no battery voltage is measured by the means for measuring.

40. The charger of claim 33, wherein the open cell battery fault is detected when the charging current is less than a predetermined current after the battery has been charging longer than a predetermined amount of time.

41. A high frequency battery charger for charging a battery, comprising:

a charging circuit including a high frequency transformer for producing a DC output signal, a switching configuration to switch the high frequency transformer to produce a charging current to charge the battery and a controller providing a high frequency driving signal to the switching configuration;

measuring circuitry for measuring at least one of a voltage or a charging current at the battery; and

a processor to calculate diagnostics based on at least one of the voltage or current, wherein the diagnostics include at least one of an overtime fault, a shorted cell fault, a bad battery fault, or an open cell fault.

42. The charger of claim 41, wherein the processor determines a charging time of the battery.

43. The charger of claim 42, wherein the processor detects the overtime fault when the charging current is greater than a predetermined current after the battery has been charging longer than a predetermined amount of time.

44. The charger of claim 42, wherein the processor detects the shorted cell battery fault when after a predetermined amount of time the battery voltage is less than or equal to a predetermined voltage.

45. The charger of claim 41, wherein the processor detects the bad battery fault when no battery voltage is measured.

46. The charger of claim 42, wherein the processor detects the open cell battery fault when the current is less than a predetermined current after the battery has been charging more a predetermined amount of time.

47. A high frequency charger, comprising:

a high frequency transformer;

a switching configuration to switch the high frequency transformer to produce a charging current for charging a battery;

a controller providing a high frequency driving signal to the switching configuration;

connectors coupled to an output of the transformer and adapted to be connected to a battery;

circuitry coupled to the connectors and operative to detect a fault with the battery; and

a display for indicating the detected fault.

48. The charger of claim 47, further comprising a temperature sensor measuring an internal temperature of the charger and providing a signal representing the temperature to the controller, the controller turning the charger off when the temperature exceeds a predetermined limit.

49. A high frequency battery charger for charging a target battery, comprising:

a high frequency transformer;

means for switching the high frequency transformer;

means coupled to the high frequency transformer for passing a DC voltage signal;

means for providing a high frequency driving signal to the switch;

means for measuring at least one of a voltage or a current at the target battery; and

means for receiving the measured voltage or current and calculating diagnostics of the target battery based on at least one of the measured voltage or current.

50. The charger of claim 49, further comprising connecting means adapted to be connected to the target battery for providing the DC voltage signal to the target battery, the means for measuring being coupled to the connecting means to measure at least one of the voltage or the current.

51. The charger of claim 49, wherein the diagnostics include at least one of an overtime fault, a shorted cell fault, a bad battery fault, or an open cell fault.

52. The charger of claim 49, wherein the means for receiving and calculating determines a charging time of the target battery.

53. The charger of claim 52, wherein the means for receiving and calculating detects the overtime fault in dependence on the charging current being greater than a predetermined current, the charging time being longer than a predetermined time, and the voltage of the battery being less than or equal to a predetermined voltage after the predetermined time.