JP4430350B2 - Storage battery automatic management device and control method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a storage battery automatic management device for a storage battery mounted on a small terminal device for communication and the like, and a control method therefor.
[0002]
[Prior art]
A small battery terminal device for communication, for example, a business phone main device for performing a call connection between a public telephone line and a plurality of telephones, is equipped with a storage battery as a backup power source for backup in the event of a power failure. An example of a backup circuit using this storage battery is shown in FIG.
[0003]
A storage battery, for example, an assembled battery 3 is connected to an energization line between the power source 1 and the load 2. The assembled battery 3 is configured by connecting a plurality of single batteries 4 such as lead batteries in series.
[0004]
Such a unit cell 4 has a so-called usable life in terms of design. However, the lifespan of the unit cell 4 is not constant and changes under the influence of the use environment temperature. For this reason, it is necessary to grasp the capacity of the unit cell 4 and determine an appropriate replacement time for the unit cell 4.
[0005]
[Problems to be solved by the invention]
A storage battery mounted on a small terminal device for communication or the like has a small capacity and is inexpensive, and therefore, it does not require much labor and cost for maintenance. In addition, since the small terminal equipment for communication is installed on the user side where no specialized maintenance staff is stationed, the user determines the necessity of replacement at his or her own discretion when a certain period after installation. It is common. For this reason, the replacement time may be lost, or the replacement may be performed in a situation where it can still be used sufficiently.
[0006]
The storage battery for backup is always charged so-called float charging in preparation for a power failure. For this reason, the positive electrode plate, which is a component of the storage battery, corrodes and expands over time. If the storage battery continues to be used without being replaced at an appropriate time, the positive electrode plate will expand excessively, causing cracks in the storage battery case, and the electrolyte contained inside the storage battery may leak to the outside. . Furthermore, the leaked electrolyte may damage nearby power supply devices, or a short circuit through the electrolyte may be formed, causing the storage battery to burn out.
[0007]
In consideration of the above circumstances, the present invention can effectively use the storage battery to the end, and can avoid inconveniences such as leakage of the electrolyte from the storage battery. It is an object of the present invention to provide a management device and a control method thereof.
[0009]
[Means for Solving the Problems]
The automatic storage battery management device of the invention according to claim 1 is composed of a plurality of single cells, and is connected to an energization line between a power source and a load via a switch, and is float-charged when the switch is closed while a power failure occurs. A battery pack for backup during a power failure, a discharge means for forming a discharge path for one of the single cells for a short time with the switch closed, and the discharge means A measuring means for measuring the voltage drop of the single cell at the time of forming a discharge path by means of, and dividing the voltage drop measured by the measuring means by the discharge current of the discharge path formed by the discharging means. Means for determining the internal resistance of the single cell, and means for determining the current capacity of the single cell by comparing the internal resistance thus determined with a previously stored internal resistance-capacitance characteristic; This request If the capacity is only to decrease to a second set value is determined as the life shortage in the one unit cell is close, the obtained capacity is first set value (<the second set value) becomes less than the above one single a determination unit and the battery is the lifetime exhaustion, if not determined to be life out in this determination means keeps closed the switch, the lifetime exhaustion by the determining means is determined to close its informed the fact, if it is determined that the lifetime out in the determining means and control means for opening this fact notifies the and said switch, voltage measurement to measure the voltage across and the individual voltages of the respective cells And when the abnormality occurs in any of the individual voltages of each of the unit cells measured by the voltage measuring unit, the abnormality of the voltage is notified, and the whole of each unit cell measured by the voltage measuring unit Is lower than the minimum starting voltage of the load. And comprises a control means, the opening to that effect to inform the and the switch.
[0012]
The control method of the automatic storage battery management apparatus of the invention according to claim 2 is composed of a plurality of single cells, connected to an energization line between a power source and a load via a switch, and float charged by closing the switch. In a storage battery automatic management device equipped with a battery pack for backup during power failure that can be discharged during a power failure, the discharge path for one of the cells is short for a short time with the switch closed. A step of measuring the voltage drop of the single cell at the time of forming the discharge path, and dividing the measured voltage drop by the discharge current of the discharge path to be formed. The step of obtaining the current capacity of the single cell by determining the internal resistance of the single cell and comparing the obtained internal resistance with the previously stored internal resistance-capacitance characteristics. If the calculated capacity is reduced to the second set value, it is determined that the one unit cell is about to expire, and the calculated capacity is equal to or less than the first set value (<second set value). wherein determining the one of the cells is life out, if not determined to be life out kept closed the switch, the lifetime exhaustion is determined to be close to notification if, When it is determined that the battery has expired, the step of notifying the fact and opening the switch, the step of measuring the overall voltage and individual voltage of each unit cell, and the step of measuring each unit cell to be measured When an abnormality occurs in any of the individual voltages, the abnormality of the voltage is notified, and when the measured overall voltage of each unit cell becomes lower than the minimum starting voltage of the load, the fact is notified, and the switching is performed. includes a step of opening the vessel, the
[0013]
DETAILED DESCRIPTION OF THE INVENTION
[1] A first embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, a storage battery, for example, an assembled battery 3 is connected to an energization line between a power source 1 and a load 2. The assembled battery 3 is configured by connecting a plurality of single batteries 4 such as lead batteries in series. A normally open contact 14a of a relay 14 described later is inserted into a connection line between the energization line and the assembled battery 3.
[0014]
In addition, an automatic storage battery management device 10 is connected to the assembled battery 3. The storage battery automatic management device 10 includes a control unit 11 as a control center. A voltage measuring unit 12, an internal resistance measuring unit 13, a switch such as a relay 14, a test switch 15, and a display unit 16 are connected to the control unit 11.
[0015]
The voltage measuring unit 12 is connected to signal lines at both ends of each unit cell 4 and measures the entire voltage and each voltage of each unit cell 4. The internal resistance measuring unit 13 uses one unit cell 4 of each unit cell 4 as a pilot cell and is connected to signal lines at both ends thereof, and measures the internal resistance of the pilot cell. The measurement results of the voltage measurement unit 12 and the internal resistance measurement unit 13 are supplied to the control unit 11.
[0016]
As a main function, the control unit 11 determines the life of the unit cell 4 according to the measurement result of the internal resistance measurement unit 13, and energizes the relay 14 when the determination unit does not determine that the life has expired. When the contact 14a is closed and the determination means determines that the service life has expired, this is notified, and the relay 14 is de-energized to open the contact 14a, and the measurement result of the voltage measurement unit 12 is less than the set value. And a control means for deactivating the relay 14 and opening the contact 14a.
[0017]
A specific example of the main part in FIG. 1 is shown in FIG.
[0018]
A DC voltage Vd of 48 V is output from the power source 1, and the output voltage is converted into a DC voltage Vc of 5 V by the control power source converter 20. The control unit 11 is operated by the DC voltage Vc. Note that the DC voltage Vd is supplied to the control unit 11 via the voltage follower 21 in order to monitor the power failure or voltage drop of the power source 1 by the control unit 11. The voltage follower 21 is an amplifier circuit having a gain of “1”, and is provided to prevent an electrical influence on the power source 1 side from reaching the control unit 11 side.
[0019]
The voltage measuring unit 12 supplies voltage followers 31 and 32 to one voltage V1 from the lower side, two voltages V2 from the lower side, three voltages V3 from the lower side, and all the voltages V4 among the unit cells 4. , 33, and 34, the total voltage and individual voltage of each unit cell 4 are measured.
[0020]
The internal resistance measurement unit 13 is connected to the discharge voltage drop measurement circuit 42 to which the voltage of one of the single cells 4 (hereinafter referred to as the pilot battery 4) is input via the voltage follower 41, and the pilot battery 4. A connected discharge circuit 43 is provided. The discharge circuit 43 includes a constant current circuit, and forms a discharge path for the pilot battery 4 only for a short time in response to a discharge command from the control unit 11. A voltage of a level corresponding to the current I flowing through the discharge path is supplied to the control unit 11 as a discharge current measurement value. The discharge voltage drop measurement circuit 42 measures a voltage drop ΔV during discharge of the pilot battery 4. The measurement result is notified to the control unit 11.
[0021]
The control unit 11 determines the internal resistance R of the pilot battery 4 by dividing the voltage drop ΔV by the discharge current I. Further, the control unit 11 obtains the current capacity P (%) of the pilot battery 4 by comparing the obtained internal resistance R with the internal resistance-capacitance characteristics of FIG. 3 stored in advance in the internal memory. And if the capacity | capacitance P has fallen to the setting value P2, the control part 11 will determine with the lifetime of the pilot battery 4 being near expiration, and will display that on the display part 16 as an alarm. When the capacity P becomes equal to or less than the set value P1 (<P2), it is determined that the pilot battery 4 has already expired, and the relay 14 is de-energized. The difference between the set values P1 and P2 corresponds to a lifetime of about one month.
[0022]
Next, the operation of the above configuration will be described.
The life of the pilot battery 4 is determined at a fixed time (periodically) based on the internal timer of the control unit 11 or when the test switch 15 is turned on. In this determination, when the pilot battery 4 is almost out of service (about one month ago), a warning to that effect is generated by the display on the display unit 16. By viewing this display, the user can recognize that the single batteries 4 of the assembled battery 4 are almost out of service life and can prepare for the introduction of new single batteries 4. Therefore, the malfunction which misses the replacement time of each cell 4 can be avoided.
[0023]
When it is determined that the pilot battery 4 has expired, a message to that effect is given on the display 16 and the relay 14 is deactivated and the contact 14a is opened. That is, the energization path from the power source 1 to the assembled battery 3 is interrupted in a state where the assembled battery 3 is used up to the end. By this interruption, unnecessary float charging for the unit cell 4 whose lifetime has expired is avoided, excessive expansion of the positive electrode plate in the unit cell 4 and the accompanying crack of the storage battery cell are prevented, and the electrolyte in the cell is externally applied. It is possible to prevent the situation from leaking in advance, and it is safe. That is, if the electrolytic solution leaks, there is a concern that a nearby power supply device may be damaged or a short circuit through the electrolytic solution may be formed and the storage battery may be burned, but such a problem can be avoided.
[0024]
On the other hand, the voltage of each unit cell 4 is measured by the voltage measurement unit 12, and when a voltage abnormality occurs in any one of the unit cells 4, the voltage abnormality is notified by display on the display unit 16. According to this notification, the unit cell 4 having an abnormal voltage can be replaced with a normal one.
[0025]
The voltage of each cell 4, that is, the voltage of the assembled battery 3 is also measured by the voltage measuring unit 12, and when the measurement result is lower than the set value, for example, lower than the minimum starting voltage of the load 2, that fact is displayed on the display unit 16. While being notified by the display, the relay 14 is de-energized and the contact 14a is opened.
When the voltage of the assembled battery 3 becomes lower than the minimum starting voltage of the load 2, the assembled battery 3 is over-discharged at the time of power failure backup, causing an early capacity decrease that significantly reduces the capacity of the assembled battery 3. However, when the contact point 14a is opened as described above, it is possible to eliminate such a problem of early capacity reduction.
[0026]
In each of the above embodiments, the assembled battery mounted on the small terminal device for communication has been described as an example, but the present invention can be similarly applied to the assembled battery mounted on another device. Moreover, although it was set as the structure which measures internal resistance by using one single cell as a pilot battery, it can implement similarly also as a structure which measures the internal resistance of all the single cells, respectively.
In addition, the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine the component covering different embodiment suitably.
[0027]
【The invention's effect】
As described above, according to the present invention, the storage battery can be used up to the end, and the storage battery automatic management excellent in reliability and safety can avoid inconveniences such as leakage of the electrolyte from the storage battery. An apparatus and a control method thereof can be provided.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.
FIG. 2 is a specific block diagram of a main part of the embodiment.
FIG. 3 is a view showing an internal resistance-capacitance characteristic of a unit cell in the same embodiment.
FIG. 4 is a block diagram showing a configuration of a general assembled battery and its peripheral part.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Power supply, 2 ... Load, 3 ... Assembly battery, 4 ... Single cell, 10 ... Storage battery automatic management apparatus, 11 ... Control part, 12 ... Voltage measurement part, 13 ... Internal resistance measurement part, 14 ... Relay (switch) 14a ... Normally open contact, 15 ... Test switch, 16 ... Display

Claims (2)

A battery pack for backup in case of power failure, which consists of a plurality of single cells, is connected to the energizing line between the power source and the load via a switch, and is float-charged by closing the switch and can be discharged at the time of power failure ,
A discharge means for forming a discharge path for one of the single cells only in a short time with the switch closed;
Measuring means for measuring the voltage drop of the single cell at the time of forming a discharge path by the discharging means;
Means for determining the internal resistance of the single cell by dividing the voltage drop measured by the measuring means by the discharge current of the discharge path formed by the discharging means;
Means for obtaining the current capacity of the single cell by comparing the obtained internal resistance with a previously stored internal resistance-capacitance characteristic;
If the calculated capacity is reduced to the second set value, it is determined that the one battery cell is about to expire, and if the calculated capacity becomes equal to or less than the first set value (<second set value), the 1 A determination means for determining that one unit cell has expired ,
If the determination means does not determine that the service life has expired , the switch is kept closed, and if the determination means determines that the service life is about to expire, it notifies that fact, and the determination means determines that the service life has expired . If it is determined that the control means for notifying to that effect and to open the switch,
Voltage measuring means for measuring the overall voltage and individual voltage of each unit cell;
When an abnormality occurs in any of the individual voltages of the unit cells measured by the voltage measuring unit, the voltage abnormality is notified, and the total voltage of the unit cells measured by the voltage measuring unit is Control means for informing that when the load voltage is lower than the minimum starting voltage of the load and opening the switch;
An automatic storage battery management device comprising: A backup battery pack consisting of a plurality of single cells, connected to the energization line between the power source and the load via a switch, and being float-charged by closing the switch and capable of discharging during a power failure In the storage battery automatic management device provided,
Forming a discharge path for one of the single cells for a short time with the switch closed ;
Measuring the voltage drop of the single cell at the time of forming the discharge path;
Dividing the measured voltage drop by the discharge current of the formed discharge path to determine the internal resistance of the single cell;
A step of obtaining a current capacity of the single cell by comparing the obtained internal resistance with a previously stored internal resistance-capacitance characteristic;
If the obtained capacity is reduced to the second set value, it is determined that the one battery cell is almost out of life, and if the obtained capacity becomes equal to or less than the first set value (<second set value), the 1 Determining that one of the cells has expired,
If it is not determined that the lifetime has expired, the switch is kept closed, and if it is determined that the lifetime has expired, this is notified, and if it is determined that the lifetime has expired, that fact is notified. a step of and opening the switch,
Measuring the overall voltage and individual voltage of each cell;
When an abnormality occurs in any of the individual voltages of the measured unit cells, the voltage abnormality is notified, and the measured overall voltage of the unit cells is lower than the minimum starting voltage of the load. And notifying the fact and opening the switch,
A method for controlling an automatic storage battery management device.

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