Uninterruptible power supply device with circuit for degradation judgment of storage battery

• US 20040196005A1
• Filed: 02/24/2004
• Published: 10/07/2004
• Est. Priority Date: 04/04/2003
• Status: Active Grant

• Current Assignee: Sanyo Denki Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Denki Company Limited (Panasonic Holdings Corporation)
• Inventors: Okui, Yoshiaki
• Granted Patent: US 7,612,468 B2
• Time in Patent Office: Days
• US Class Current: 320/132
• CPC Class Codes: H02J 7/005 Detection of state of health [SOH]
• CPC Class Codes: H02J 7/02 for charging batteries from ac mains by converters
• CPC Class Codes: H02J 9/062 for AC powered loads

Abstract

There is herein provided an uninterruptible power supply device with a degradation judgment circuit 4 of a storage battery 2 which can perform an exact judgment, continuing the power supply to a load apparatus 8 stably without giving the excessive burden to the storage battery 2. The storage battery 2 is floatingly charged from a rectifier 1 connected with the power source 10. The device has the control circuit 3 for controlling the output voltage of the rectifier 1 and the degradation judgment circuit 4. The output voltage of the rectifier 1 is lowered to below a steady state by the control circuit 3. As a result, the storage battery 2 discharges with the current Idc restricted rather than rated discharge current. And a part of power supply is supplied to the load 8. The degradation judgment circuit 4 judges the degradation of the storage battery based on the discharge voltage Vdc.

Claims

1. An uninterruptible power supply device for supplying power to a load and charging floatingly to a storage battery from a converter connecting to a alternating current power source, with the degradation judgment circuit of the storage battery, comprising;

a control circuit for controlling an output voltage of the converter to lower below a steady state, the storage battery thus to discharge at a more limited current than the rated current thereof, and the converter to supply a part of load current to the load; and

a judgment circuit for judging the degradation of the storage battery based on the discharge voltage of the limited discharge current.

3. The uninterruptible power supply device according to claim 1, wherein said converter is a rectifier and said load includes a direct-alternating current inverter in addition to a whole load apparatus.

4. The uninterruptible power supply device according to claim 1, wherein said converter is a rectifier and a direct-alternating current inverter is connected on midway between the storage battery and the load.

5. The uninterruptible power supply device according to claim 1, wherein said converter comprises a mutual transducer of direct and alternating current, which connects to the power source in parallel with the load, and which connects the storage battery thereto.

6. The uninterruptible power supply device according to claim 1, wherein said converter comprises a transducer of alternating and direct current which connects to the power source in parallel with the load, and which connects the storage battery and a direct-alternating current inverter.

7. The uninterruptible power supply device according to claim 1, wherein said limited discharge current of the storage battery, by controlling the output voltage of the converter to lower below the steady state, is almost constant what is equivalent to 10-50% of the maximum current of the load.

8. The uninterruptible power supply device according to claim 1, wherein said control circuit connects to a trigger signal source which comprises memory memorized an operational schedule of the degradation judgment, and the converter starts to lower the output voltage at the timing of the trigger signal and the storage battery then starts to discharge.

9. The uninterruptible power supply device according to claim 1, wherein said converter and said control circuit comprise a rectifier for obtaining a direct current from the alternating current power source, and a closing loop for bringing the voltage of the direct current close to an appointed direct current voltage with a pulse duration modulation control for an alternating input voltage of itself.

10. The uninterruptible power supply device according to claim 1, wherein said degradation judgment circuit comprises a comparator for comparing between an appointed value of a direct current voltage from the control circuit and the discharge voltage of the storage battery.

11. The uninterruptible power supply device according to claim 1, wherein said degradation judgment circuit comprises an integration circuit for integrating with a voltage difference between the appointed value of the direct current voltage form the control circuit and a discharge voltage of the storage battery, and a comparator for comparing between the output voltage of the integration circuit and a standard voltage.

2. An uninterruptible power supply device for supplying power to a load and charging floatingly to a storage battery from a converter connecting to a alternating current power source, with the degradation judgment circuit of the storage battery, comprising;

a control circuit for controlling an output voltage of the converter to lower below a steady state, the storage battery thus to discharge at a more limited current than the rated current thereof, and the converter to supply a part of load current to the load; and

a judgment circuit judges the degradation of the storage battery based on a charging time of the storage battery from when controlling, by the control circuit, the converter to return the output voltage to the steady state until completing full charge state thereof.

12. The uninterruptible power supply device according to claim 2, wherein said degradation judgment circuit comprises a timer for measuring the charge time of the storage battery.

13. The uninterruptible power supply device according to claim 2, wherein said degradation judgment circuit comprises a timer connecting to a comparator for comparing a charging current of the storage battery with a of base current.

14. The uninterruptible power supply device according to claim 2, wherein said converter is a rectifier and said load includes a direct-alternating current inverter in addition to a whole load apparatus.

15. The uninterruptible power supply device according to claim 2, wherein said converter is a rectifier and a direct-alternating current inverter is connected on midway between the storage battery and the load.

16. The uninterruptible power supply device according to claim 2, wherein said converter comprises a mutual transducer of direct and alternating current, which connects to the power source in parallel with the load, and which connects the storage battery thereto.

17. The uninterruptible power supply device according to claim 2, wherein said converter comprises a transducer of alternating and direct current which connects to the power source in parallel with the load, and which connects the storage battery and a direct-alternating current inverter.

18. The uninterruptible power supply device according to claim 2, wherein said limited discharge current of the storage battery, by controlling the output voltage of the converter to lower below the steady state, is almost constant what is equivalent to 10-50% of the maximum current of the load.

19. The uninterruptible power supply device according to claim 2, wherein said control circuit connects to a trigger signal source which comprises memory memorized an operational schedule of the degradation judgment, and the converter starts to lower the output voltage at the timing of the trigger signal and the storage battery then starts to discharge.

20. The uninterruptible power supply device according to claim 2, wherein said converter and said control circuit comprise a rectifier for obtaining a direct current from the alternating current power source, and a closing loop for bringing the voltage of the direct current close to an appointed direct current voltage with a pulse duration modulation control for an alternating input voltage of itself.