JP2005045950A - Charger, non-interruptible power supply device, and deterioration determination method for battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To determine the deterioration of a battery without causing the discharge of the battery. <P>SOLUTION: A prescribed waiting time is made to elapse after charging the battery 14 with a constant current. A deterioration determination part 76 determines the deterioration of the battery 14 on the basis of a storage voltage of the battery 14 during the lapse of the prescribed waiting time. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a charging device for charging a battery, an uninterruptible power supply, and a battery deterioration determination method.

  Patent Document 1 discloses an uninterruptible power supply. This conventional uninterruptible power supply includes a battery, a voltage monitoring unit, and a control unit. In this conventional uninterruptible power supply, the battery voltage during battery discharge is continuously measured with the load device added to the uninterruptible power supply, and the controller determines the deterioration of the battery based on the discharge curve. ing.

JP-A-6-98471 (Embodiment of the Invention, FIG. 6, FIG. 7, FIG. 8)

  As described above, the conventional uninterruptible power supply recognizes a certain correlation between the discharge curve of the battery voltage and the deterioration state of the battery, measures the discharge curve of the battery, and determines the measured discharge curve and deterioration. The deterioration state of the battery is determined by comparing the discharge curve of the battery.

  However, in the conventional uninterruptible power supply, deterioration cannot be determined unless the battery is discharged. Moreover, in the conventional uninterruptible power supply, the load which has a fixed discharge characteristic will be needed for the battery discharge at the time of the battery deterioration determination.

  In addition, even if it is a battery used other than an uninterruptible power supply, in order to determine the deterioration of the battery, the battery is discharged. In addition, a load corresponding to the discharge characteristics to be measured is required for the battery discharge for determining the battery deterioration.

  The present invention has been made in view of the above problems, and an object of the present invention is to obtain a battery charger, an uninterruptible power supply, and a battery deterioration determination method that can perform battery deterioration determination without discharging the battery. .

  A charging device according to the present invention is a charging device for charging a battery, a detector for detecting a storage voltage of the battery, constant current charging means for charging the battery at a constant current, and constant voltage charging for charging the battery at a constant voltage. A deterioration determining means for determining deterioration of the battery based on the storage voltage of the battery, and when the battery has been subjected to constant current charging by the constant current charging means and then a predetermined waiting time has elapsed, the deterioration determining means Control means for making a determination and further charging the battery at a constant voltage by the constant voltage charging means.

  If this configuration is adopted, a predetermined waiting time is provided between the constant current charging of the battery and the constant voltage charging, and based on the stored voltage of the battery after the predetermined waiting time has elapsed, Perform deterioration judgment. Therefore, battery deterioration can be determined without discharging the battery.

  An uninterruptible power supply according to the present invention includes an input terminal to which a first voltage is applied, a first conversion circuit that converts the first voltage into a second voltage, and a second voltage that is converted into a third voltage. A second conversion circuit for converting to a voltage, an output terminal for outputting a third voltage, a battery, a detector for detecting a storage voltage of the battery, and a charging voltage for constant current charging from the second voltage A constant current charging means; a constant voltage charging means for generating a charging voltage for constant voltage charging from the second voltage; a deterioration determining means for determining battery deterioration based on a battery storage voltage; and a constant current charging means. Control means for charging the battery at a constant charging voltage at a predetermined charging voltage and then determining whether the battery has deteriorated by a deterioration determining means after a predetermined waiting time has elapsed, and charging the battery with a charging voltage for constant voltage charging; , Has.

  If this configuration is adopted, a predetermined waiting time is provided between the constant current charging of the battery and the constant voltage charging, and based on the stored voltage of the battery after the predetermined waiting time has elapsed, Perform deterioration judgment. Therefore, battery deterioration can be determined without discharging the battery.

  In the uninterruptible power supply according to the present invention, in addition to the configuration of the above-described invention, the deterioration determination means is configured such that the open voltage of the battery after a predetermined waiting time has elapsed When the predetermined waiting time has elapsed after charging up to the voltage, the battery is determined to be deteriorated if it is equal to or lower than the open voltage of the deteriorated battery.

  If this configuration is adopted, since the determination voltage based on the actually opened battery open voltage is used as the threshold voltage, it is possible to accurately determine the deterioration of the battery.

  In the uninterruptible power supply according to the present invention, in addition to the respective configurations of the above-described invention, the control means periodically charges.

  If this configuration is adopted, the control means periodically charges, so that it is possible to automatically detect deterioration of the battery over time during continuous operation of the apparatus.

  A battery deterioration determination method according to the present invention includes a step of charging a battery at a constant current, a step of waiting for a predetermined time after completion of constant current charging, a battery storage voltage and a predetermined reference voltage after elapse of the waiting time. And determining whether or not the battery has deteriorated.

  If this method is adopted, the battery deterioration is determined based on the stored voltage of the battery after the battery is charged with a constant current and a predetermined waiting time elapses. Therefore, battery deterioration can be determined without discharging the battery.

  In the present invention, it is possible to determine battery deterioration without discharging the battery.

    Hereinafter, a charging device, an uninterruptible power supply, and a battery deterioration determination method according to the best mode for carrying out the present invention will be described with reference to the drawings. The charging device will be described as a part of the uninterruptible power supply. The battery deterioration determination method will be described as part of the operation of the uninterruptible power supply.

  FIG. 1 is a block diagram showing an uninterruptible power supply 1 according to an embodiment of the present invention.

  The uninterruptible power supply 1 according to this embodiment has a pair of input terminals 2 and 3. An AC power supply device 4 such as a commercial AC power supply is connected to the pair of input terminals 2 and 3. The commercial AC power supply outputs AC power having an AC voltage with an amplitude of about 140 V at a predetermined frequency such as 50 Hz or 60 Hz. AC power having this AC voltage is supplied to the pair of input terminals 2 and 3 as an input voltage as the first voltage.

  The pair of input terminals 2 and 3 are connected to a rectifier circuit 8 as a first conversion circuit. The rectifier circuit 8 has a transistor (not shown) and converts an AC voltage into a DC voltage. The rectifier circuit 8 is connected to a pair of rail wires 9 and 10. A rail capacitor 11 is connected between the pair of rail wirings 9 and 10.

  The pair of rail wirings 9 and 10 are connected to an inverter circuit 12 as a second conversion circuit. The inverter circuit 12 has a transistor (not shown) and converts a DC voltage into an AC voltage. The inverter circuit 12 is connected to a pair of output terminals 5 and 6. A load device 7 such as a computer is connected to the pair of output terminals 5 and 6.

  The pair of rail wires 9 and 10 are connected to a charging circuit 13 as a constant current charging unit and a constant voltage charging unit. FIG. 2 is a circuit diagram showing the charging control unit 32, the charging circuit 13 and the peripheral portion in FIG.

  In FIG. 2, the charging circuit 13 includes a charging transformer 51, a charging transistor 52, a first charging diode 53, a charging capacitor 54, and a second charging diode 55. One end of the primary coil of the charging transformer 51 is connected to the plus-side rail wiring 9 in the pair of rail wirings 9 and 10. The other end of the primary coil is connected to the collector of the charging transistor 52. The emitter of the charging transistor 52 is connected to the negative rail wiring 10 in the pair of rail wirings 9 and 10. The cathode of the first charging diode 53 is connected to the plus-side rail wiring 9. The anode of the first charging diode 53 is connected to the collector of the charging transistor 52. One end of the secondary coil of the charging transformer 51 is connected to the anode of the second charging diode 55. The charging capacitor 54 is connected between the cathode of the second charging diode 55 and the other end of the secondary coil. Further, the battery 14 is connected in parallel with the charging capacitor 54.

  Further, as shown in FIG. 1, the battery 14 is connected to the discharge circuit 15. The discharge circuit 15 has a transistor (not shown). The discharge circuit 15 is connected to a pair of rail wirings 9 and 10.

  The uninterruptible power supply 1 according to this embodiment includes an input voltage detector 21 and a storage voltage detector 22 as a detector. The input voltage detector 21 detects the voltage at one input terminal 2 with reference to the voltage level at the other input terminal 3, and outputs a voltage having a level corresponding to the magnitude of the detected voltage as a detected input voltage. The stored voltage detector 22 detects the stored voltage of the battery 14 and outputs a voltage at a level corresponding to the detected voltage as a detected stored voltage.

  The input voltage detector 21 and the storage voltage detector 22 are connected to a DSP (Digital Signal Processor) 23. The DSP 23 is a kind of microprocessor, and generates various control signals by digital signal processing.

  The DSP 23 is connected to a lamp 41 and a communication interface unit 42. The communication interface unit 42 transmits data input from the DSP 23 to a predetermined transmission destination such as a computer as the load device 7 that is fed by the uninterruptible power supply 1.

  The DSP 23 periodically samples the detected input voltage to generate a digital value of the detected input voltage, and the second AD 23 periodically samples the detected stored voltage to generate a digital value of the detected stored voltage And an AD converter 25.

  The DSP 23 includes a rectifier control unit 31, a charge control unit 32, a discharge control unit 33, an inverter control unit 34, a mode control unit 35, and a timer 36. The rectifier control unit 31, the charge control unit 32, the discharge control unit 33, the inverter control unit 34, and the mode control unit 35 are configured so that a microprocessor (not shown) in the DSP 23 stores a control program stored in a memory (not shown). It is realized by executing.

  The rectifier control unit 31 outputs to the transistor of the rectifier circuit 8 a gate signal for switching the transistor between an on state and an off state.

  As shown in FIG. 2, the charging control unit 32 includes a constant voltage target register 61, a constant voltage subtractor 62, a fixed error voltage register 63, a selector 64, a command value calculation unit 65, and a triangular wave data generator 66. A comparator 67, a constant current target voltage register 71, a constant current subtractor 72, a switching control unit 73 as a control means, a determination voltage register 74, a determination voltage subtractor 75, and a deterioration determination means. A deterioration determination unit 76.

  The fixed error voltage register 63 stores a fixed value error voltage used for constant current charging as a fixed error voltage.

  The constant voltage target register 61 stores a constant voltage charging voltage that is a target voltage when the battery 14 is charged at a constant voltage. The constant voltage subtracter 62 subtracts the detected storage voltage output from the second AD converter 25 from the constant voltage charging voltage stored in the constant voltage target register 61.

  The selector 64 selects one of the fixed error voltage register 63 and the output value of the constant voltage subtracter 62 as the error voltage. The command value calculation unit 65 calculates a command value for charging the battery 14 based on an error voltage selected by the selector 64 by a primary IIR (Infinite-Duration Impulse Response) filter calculation process or the like. The command value calculator 65 outputs a smaller value as the error voltage is larger, and outputs a larger value as the error voltage is smaller.

  The triangular wave data generator 66 outputs a digital value. This digital value is a value that changes with the passage of time, like a sampling value obtained when a triangular wave is sampled. The comparator 67 compares the digital value of the triangular wave from the triangular wave data generator 66 with the command value from the command value calculation unit 65. The comparator 67 outputs a positive pulse when the digital value of the triangular wave is larger than the command value. Further, the pulse width of the pulse becomes wider as the command value is smaller.

  The comparator 67 is connected to the gate of the charging transistor 52 of the charging circuit 13. The charging transistor 52 is turned on when a pulse is output from the comparator 67, and is turned off when a pulse is not output from the comparator 67. As a result, the charging transistor 52 performs a switching operation with the gate signal output from the comparator 67.

  The constant current target voltage register 71 stores a constant current charging voltage that is a target voltage when the battery 14 is charged with constant current. This constant current charging voltage is set to a voltage of about 2.35 V / Cel, for example, and is higher than the constant voltage charging voltage (2.30 V / Cel). The constant current subtracter 72 subtracts the detected storage voltage output from the second AD converter 25 from the constant current charging voltage stored in the constant current target voltage register 71.

  The switching control unit 73 is connected to the mode control unit 35, timer 36, constant voltage subtractor 62, and constant current subtractor 72. Based on the inputs from the mode control unit 35, timer 36, constant voltage subtractor 62, and constant current subtractor 72, a selection signal is output to the selector 64 and a determination command signal is output to the deterioration determination unit 76. .

  The determination voltage register 74 stores a determination voltage that serves as a threshold voltage when determining deterioration of the battery 14. The determination voltage is a constant current target voltage and a voltage lower than the constant voltage target voltage, and uses a determination voltage based on the open circuit voltage of the battery 14 that has actually deteriorated, as will be described later. The determination voltage subtracter 75 subtracts the detected storage voltage output from the second AD converter 25 from the determination voltage stored in the determination voltage register 74.

  The deterioration determination unit 76 determines the deterioration state of the battery 14 based on the calculation result of the determination voltage subtracter 75. When the deterioration determination unit 76 determines that the battery 14 is deteriorated, the deterioration determination unit 76 turns on the lamp 41 and outputs data indicating the deterioration of the battery 14 to the communication interface unit 42.

  The discharge controller 33 in FIG. 1 outputs to the transistor of the discharge circuit 15 a gate signal for switching the transistor between an on state and an off state.

  The inverter control unit 34 outputs to the transistor of the inverter circuit 12 a gate signal that causes the transistor to switch between an on state and an off state. The timer 36 measures time.

  The mode control unit 35 outputs a start signal and a stop signal to the rectifier control unit 31, the charge control unit 32, the discharge control unit 33, and the inverter control unit 34, respectively. Further, the mode control unit 35 controls turning on / off of the lamp 41 and outputs predetermined data to the communication interface unit 42 (communication I / F unit). The communication interface unit 42 transmits the input data to, for example, a computer as the load device 7.

  Next, the operation of the uninterruptible power supply 1 based on the control by the mode control unit 35 will be described.

  An AC power supply device 4 is connected to the pair of input terminals 2 and 3 of the uninterruptible power supply device 1. A load device 7 is connected to the pair of output terminals 5 and 6. When the central processing unit of the DSP 23 executes the control program, the rectifier control unit 31, the charge control unit 32, the discharge control unit 33, the inverter control unit 34, and the mode control unit 35 are realized.

  When the uninterruptible power supply 1 is activated, the mode control unit 35 outputs a stop signal to the rectifier control unit 31, the charge control unit 32, the discharge control unit 33, and the inverter control unit 34. Therefore, the rectifier control unit 31, the charge control unit 32, the discharge control unit 33, and the inverter control unit 34 are stopped.

  The mode control unit 35 first outputs an activation signal to the discharge control unit 33. Thus, a discharge voltage as a second voltage based on the stored voltage of the battery 14 is output from the discharge circuit 15 based on the gate signal from the discharge control unit 33, and the rail capacitor 11 is charged to this discharge voltage. As a result, the potential difference between the pair of rail wirings 9 and 10 becomes this discharge voltage.

  After outputting the start signal to the discharge control unit 33, the mode control unit 35 outputs the start signal to the inverter control unit 34. Thus, an AC voltage as a third voltage based on the potential difference between the pair of rail wirings 9 and 10 is applied to the pair of output terminals 5 and 6 from the inverter circuit 12 based on the gate signal from the inverter control unit 34. Is done. The load device 7 operates with AC power having this AC voltage.

  After outputting the activation signal to the inverter control unit 34, the mode control unit 35 starts monitoring the input voltages of the pair of input terminals 2 and 3 based on the detected input voltage. When the input voltage is normal, the mode control unit 35 outputs an activation signal to the rectifier control unit 31. In addition, after outputting a start signal to the rectifier control unit 31, the mode control unit 35 outputs a stop signal to the discharge control unit 33. As a result, the output of the gate signal from the discharge control unit 33 stops, and the charging voltage of the rail capacitor 11 changes from the discharging voltage to the DC voltage from the rectifier circuit 8. As a result, the uninterruptible power supply device 1 converts the AC power from the AC power supply device 4 into other AC power from the state in which the stored power of the battery 14 is converted into AC power and supplied to the load device 7. The state is switched to the state of supplying to the load device 7. This completes the activation process.

  Even after such activation processing, the mode control unit 35 continues to monitor the input voltage. When the input voltage cannot be determined to be normal due to, for example, a power failure, the mode control unit 35 outputs a start signal to the discharge control unit 33 and outputs a stop signal to the rectifier control unit 31. Thereby, the uninterruptible power supply 1 switches from a state in which the AC power from the AC power supply 4 is supplied to the load device 7 to a state in which the stored power of the battery 14 is supplied to the load device 7.

  When the input voltage returns to a normal state, the mode control unit 35 outputs a start signal to the rectifier control unit 31 and outputs a stop signal to the discharge control unit 33. Thereby, the uninterruptible power supply device 1 converts the stored power of the battery 14 into AC power and supplies it to the load device 7, and then loads the AC power from the AC power supply device 4 through AC / DC and orthogonal transformation. 7 is switched to the supply state.

  Even if the input power becomes abnormal due to the switching process of the power supply based on the control of the mode control unit 35 described above, the potential difference between the pair of rail wirings 9 and 10 is maintained at a desired potential difference. 12 continues to supply stable AC power to the load device 7. Since the load device 7 continues to be supplied with stable AC power from the inverter circuit 12, the load device 7 can continue to operate.

  Further, when the activation process is completed, the mode control unit 35 starts monitoring the detected storage voltage. When the detected storage voltage becomes equal to or lower than the predetermined minimum storage voltage, it is confirmed that the activation signal is output to the rectifier control unit 31, and then the activation signal is output to the charge control unit 32. At this time, the activation signal is not supplied to the discharge controller 33. That is, the discharge circuit 15 does not operate and the battery 14 is in a no-load state. Further, after the start process is completed, the mode control unit 35 outputs a start signal to the charge control unit 32 periodically, for example, every 30 days based on the measurement time of the timer 36. The period for outputting the activation signal to the charging control unit 32 based on the measurement time of the timer 36 may be a constant period other than 30 days or may be irregular.

  The activation signal to the charging control unit 32 is input to the switching control unit 73. FIG. 3 is a characteristic diagram showing a charging curve by the charging process of the switching control unit 73 in FIG. In FIG. 3, the horizontal axis is time, and the vertical axis is the detected storage voltage of the battery 14. The charging curve of Example 1 indicated by the solid line is a charging curve of the battery 14 that has not deteriorated, and the charging curve of Example 2 indicated by the broken line is a charging curve of the battery 14 that has deteriorated.

  The switching control unit 73 outputs a selection signal for causing the selector 64 to select the fixed error voltage register 63 together with the start of charging (time T0). Accordingly, the command value calculation unit 65 calculates a command value based on the fixed error voltage, and the comparator 67 compares the triangular wave digital value with this command value, and outputs a pulse as a gate signal to the charging transistor 52. Output. The charging transistor 52 performs a switching operation with this gate signal, whereby a voltage is generated in the primary coil of the charging transformer 51. Since the first charging diode 53 is connected in parallel with the primary side coil, only the positive voltage (the upward voltage in FIG. 2) at which the potential at one end is higher than the other end is applied to the primary side coil. appear. Due to the positive voltage excited in the primary side coil, a positive voltage is also generated in the secondary side coil of the charging transformer 51. The positive voltage excited in the secondary coil is rectified by the second charging diode 55 and the charging capacitor 54 and applied to the battery. The battery 14 is charged with this rectified voltage.

  After outputting a selection signal for selecting the fixed error voltage register 63 to the selector 64, the switching control unit 73 monitors the calculation result of the constant current subtracter 72. The constant current subtracter 72 subtracts the detected storage voltage from the constant current charging voltage. When the calculation result of the constant current subtractor 72 becomes 0 or less, the switching control unit 73 ends the selection of the fixed error voltage register 63 by the selector 64 (time T1). Thereby, the battery 14 is charged to a constant current charging voltage with a constant power based on the fixed error voltage. That is, the battery 14 is charged with a constant current up to a constant current charging voltage.

  The switching control unit 73 monitors the elapsed time from the timing when the selection of the fixed error voltage register 63 by the selector 64 is ended based on the output value of the timer 36. At this time, the switching control unit 73 stops the output from the selector 64 and stops the operation of the charging circuit 13. That is, the battery 14 is in an open state. When this time exceeds a predetermined waiting time such as 3 minutes (time T <b> 2), switching control unit 73 outputs a determination command signal to deterioration determination unit 76.

  The deterioration determination unit 76 receives a calculation result of a determination voltage subtracter 75 obtained by subtracting the detected storage voltage from a determination voltage serving as a reference for deterioration determination. When the determination command signal is input, the deterioration determination unit 76 determines the deterioration state of the battery 14 based on the calculation result of the determination voltage subtracter 75 at that timing.

  During the previous waiting time (time T1 to time T2), the storage voltage of the battery 14 charged to a constant current charging voltage by constant current charging decreases. As shown in the charging curve of Example 1 and the charging curve of Example 2 in FIG. 3, as the battery 14 deteriorates, the stored voltage of the battery 14 greatly decreases during this period.

  Then, the deterioration determination unit 76 determines that the battery 14 is deteriorated when the calculation result of the determination voltage subtracter 75 at the timing when the determination command signal is input is 0 or less, and turns on the lamp 41. In addition, data indicating deterioration of the battery 14 is output to the communication interface unit 42. The communication interface unit 42 transmits this data to a predetermined transmission destination (for example, a load device 7 such as a computer). When the calculation result of the determination voltage subtracter 75 is greater than 0, the deterioration determination unit 76 maintains the lamp 41 in the off state.

  Therefore, as shown in the charging curve of Example 1 of FIG. 3, in the battery 14 which has not deteriorated, the calculation result of the determination voltage subtracter 75 at the timing when the determination command signal is input becomes larger than 0. 41 does not light up, and the communication interface unit 42 does not transmit data notifying the deterioration.

  On the contrary, as shown in the charging curve of Example 2 in FIG. 3, in the deteriorated battery 14, the calculation result of the determination voltage subtracter 75 at the timing when the determination command signal is input becomes 0 or less. 41 is turned on, and the communication interface unit 42 transmits data for notifying deterioration.

  After outputting the determination command signal to the deterioration determination unit 76, the switching control unit 73 outputs a selection signal for causing the selector 64 to select the output value of the constant voltage subtractor 62. Therefore, the command value calculation unit 65 calculates a command value corresponding to the stored voltage of the battery 14 at each time point, and the comparator 67 compares the digital value of the triangular wave with this command value, and sends it to the charging transistor 52. A pulse as a gate signal is output. When the charging transistor 52 performs a switching operation with this gate signal, the battery 14 is charged with a voltage excited by the charging transformer 51.

  After outputting the selection signal for selecting the output value of the constant voltage subtractor 62 to the selector 64, the switching control unit 73 monitors the calculation result of the constant voltage subtractor 62. The constant voltage calculator subtracts the detected storage voltage from the constant voltage charging voltage. When the operation result of the constant voltage subtractor 62 becomes 0 or less, the switching control unit 73 ends the selection of the output value of the constant voltage subtractor 62 by the selector 64. As a result, the battery 14 is charged up to the constant voltage charge voltage with electric power corresponding to the error voltage of the detected storage voltage with respect to the constant voltage charge voltage. That is, the battery 14 is charged at a constant voltage up to a constant voltage charging voltage.

  By the charging process of the battery 14 by the charge control unit 32 described above, the stored voltage of the battery 14 is maintained at a constant voltage charge voltage higher than the minimum stored voltage. Therefore, the electric power stored in the battery 14 can be supplied to the load device 7 when the input electric power becomes abnormal while maintaining the stored voltage of the battery 14 at a constant voltage charging voltage.

  In addition, the charging control unit 32 waits for a predetermined time after the constant current charging and determines the deterioration state of the battery 14 based on the open voltage of the battery 14 before starting the constant voltage charging. When the battery is deteriorated as much as necessary, the lamp 41 is turned on and the communication interface unit 42 notifies this fact, so that the user can replace the deteriorated battery 14.

  The determination voltage used as a threshold value for determining the deterioration of the battery 14 is, for example, forcibly deteriorating the battery 14 having the same standard as that of the battery 14 used in the uninterruptible power supply device 1, and Similarly, constant current charging may be performed, and furthermore, an open circuit voltage after a predetermined waiting time for the constant current charging may be used. In order to forcibly deteriorate the battery 14, the battery 14 may be repeatedly charged and discharged.

  In addition, the determination voltage and the waiting time are not determined for the battery 14 alone, but become different values as the specifications of the uninterruptible power supply 1 change. That is, the determination voltage and the waiting time differ depending on the type and number of the batteries 14 used in the uninterruptible power supply 1. Therefore, although the predetermined waiting time after constant current charging is set to 3 minutes in the above embodiment, the value of this waiting time varies depending on the specifications of the uninterruptible power supply 1 and the like.

  As described above, in this embodiment, a predetermined waiting time is provided between the constant current charging of the battery 14 and the constant voltage charging, and the storage voltage of the battery 14 when the predetermined waiting time elapses. Based on the above, the deterioration of the battery 14 is determined. Therefore, it is possible to determine the deterioration of the battery 14 without discharging the battery 14.

  Further, as the determination voltage used for determining the deterioration of the battery 14, a determination voltage based on the actually opened open voltage of the battery 14 is used. Therefore, it is possible to accurately determine the deterioration of the battery 14.

  Furthermore, in this embodiment, since the activation signal from the mode control unit 35 is periodically input, it is possible to automatically detect deterioration with time of the battery 14 during operation of the uninterruptible power supply 1. .

  The above-described embodiment is an example of a preferred embodiment of the present invention, but the present invention is not limited to this, and various modifications and changes can be made without departing from the scope of the present invention. Is possible.

  In the embodiment described above, the determination voltage register 74 stores the actually opened battery open-circuit voltage, and the determination voltage subtractor 75 calculates the detected storage voltage from the determination voltage stored in the determination voltage register 74. Subtraction is performed, and the deterioration determination unit 76 determines that the deterioration has occurred when the calculation result of the determination voltage subtractor 75 becomes 0 or less. In addition to this, for example, the determination voltage register 74 stores a differential voltage with respect to the constant current target charge of the open circuit voltage in the deteriorated battery 14, and the determination voltage subtractor 75 outputs the output of the constant current subtractor 72 from this differential voltage. The value may be subtracted, and the deterioration determination unit 76 may determine that the deterioration has occurred when the calculation result of the determination voltage subtractor 75 becomes 0 or less.

  Examples of the battery 14 used in such an uninterruptible power supply device include a cathode absorption type sealed lead acid battery and a sealed lead acid battery. Other batteries include, for example, a nickel cadmium battery, a nickel metal hydride battery, and a lithium ion battery.

FIG. 1 is a block diagram showing an uninterruptible power supply according to an embodiment of the present invention. FIG. 2 is a circuit diagram illustrating the charge control unit, the charging circuit, and the peripheral portions thereof in FIG. FIG. 3 is a characteristic diagram showing a charging curve by the charging process of the switching control unit in FIG.

Explanation of symbols

1 Uninterruptible power supply 2 One input terminal (input terminal)
3 The other input terminal (input terminal)
5,6 A pair of output terminals (output terminals)
8 Rectifier circuit (first conversion circuit)
12 Inverter circuit (second conversion circuit)
13 Charging circuit (constant current charging means, constant voltage charging means)
14 Battery 22 Storage voltage detector (detector)
36 timer 73 switching control unit (control means)
76 Degradation determination unit (degradation determination means)

Claims (5)

A charging device for charging a battery,
A detector for detecting the storage voltage of the battery;
Constant current charging means for charging the battery with constant current;
Constant voltage charging means for charging the battery at a constant voltage;
Deterioration determining means for determining deterioration of the battery based on the storage voltage of the battery;
When the battery is charged with a constant current by the constant current charging means and then a predetermined waiting time elapses, the deterioration determining means performs a deterioration determination of the battery, and the constant voltage charging means determines the battery. And a control means for charging the voltage. An input terminal to which a first voltage is applied;
A first conversion circuit for converting the first voltage into a second voltage;
A second conversion circuit for converting the second voltage into a third voltage;
An output terminal for outputting the third voltage;
Battery,
A detector for detecting the storage voltage of the battery;
Constant current charging means for generating a charging voltage for constant current charging from the second voltage;
Constant voltage charging means for generating a charging voltage for constant voltage charging from the second voltage;
Deterioration determining means for determining deterioration of the battery based on the storage voltage of the battery;
The battery is constant-current charged at a predetermined charging voltage by the constant-current charging means, and then a deterioration determination of the battery is performed by the deterioration determining means after a predetermined waiting time has elapsed. And an uninterruptible power supply comprising a control means for charging the battery with a charging voltage.   When the predetermined waiting time has elapsed after the open circuit voltage of the battery after the predetermined waiting time has elapsed, the deteriorated battery is charged to the predetermined charging voltage by constant current charging. The uninterruptible power supply according to claim 2, wherein the battery is determined to be deteriorated when it is equal to or lower than the open circuit voltage of the deteriorated battery.   The uninterruptible power supply according to claim 2, wherein the control means performs charging periodically. Charging the battery with constant current; and
Waiting for a predetermined time after completion of the constant current charging;
Comparing the stored voltage of the battery after the elapse of the waiting time with a predetermined reference voltage, and determining whether or not the battery has deteriorated.

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