JPH1091538A - Method and device for detecting life of backup battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize remote maintenance and to prevent the malfunction of a device by detecting voltage fluctuation based on a load which is set in a pseudo load generation circuit. SOLUTION: Load data is generated to the pseudo load generation circuit 5 from CPU 2 and the use time of a battery 4 is operated against a voltage fluctuation value by the pseudo load in CPU 2. The time of the life of the battery 4 is calculated and it is warned by a display device. When the voltage fluctuation value against the pseudo load becomes not more than 1.2V and a calculation result in CPU 2 becomes 'The life of battery already expires', whether the content of RAM 1 is destroyed or not is checked. When the content of RAM 1 is judged to be destroyed, precise data is written into RAM 1 and the system moves to a constant operation. When an abnormal state such as a power cut occurs, a switch S2 is turned on, backup voltage V2 is supplied through the pseudo load generation circuit 5 and a diode D2 and the content of RAM 1 is kept without being destroyed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting the life of a backup battery for backing up a RAM when an abnormality such as a power failure occurs.

[0002]

2. Description of the Related Art Generally, a microprocessor (hereinafter referred to as M)
A device using a PU (for example, a process control device such as a power plant) has a RAM for storing data necessary for control. Therefore, if the contents of the RAM are destroyed, the subsequent control is not performed. To prevent this, a backup battery is used to prevent the contents of the RAM from being destroyed even when an unpredictable abnormal state such as a power failure occurs.

[0003] The prior art will be described in detail with reference to FIG. 9. Conventionally, as shown in FIG.
For M10, the system power supply voltage V1 is a diode
11 and the voltage V2 from the backup battery 12 is supplied.

[0004] The RAM 10 has data blocks corresponding to various data, and the program is set so that data is sequentially read from the data blocks and a data check is performed.

That is, when the system power is turned on, an abnormality has occurred in the data in the RAM 10 by comparing the data stored in an arbitrary data block of the RAM 10 with the check data stored in the check data storage area. First, it is checked whether an abnormality has occurred in the RAM 10. If an abnormality has occurred in the RAM 10, predetermined data is further written and read into the RAM 10, and the written data is compared with the read data to thereby determine the RAM 10 itself. Or the backup battery 12 was abnormal.

[0006]

However, in this prior art, it is not possible to predict the abnormality (lifetime) only by detecting the presence or absence of an abnormality, so that a remote device requiring remote maintenance, for example, a reservoir, In the case of a remote monitoring and control device with controlled sites installed in mountainous areas or places where traffic is inconvenient such as intake reservoirs and pumping stations, even if it is detected that there is a "battery error", it is quick. In most cases, it was not possible to deal with

Accordingly, it is an object of the present invention to provide a method for controlling a backup battery even if an abnormality occurs in a backup battery of a remote device.
An object of the present invention is to prevent the destruction of AM contents in advance.

[0008]

In order to achieve the object, the present invention provides a means for detecting whether a battery is abnormal when power is turned on, and a means for predicting a battery abnormality in advance.

That is, according to the present invention, in the event of an abnormality, a data storage memory RAM is used with a backup battery.
In a backup system, after writing check data to the data storage memory, the backup battery is connected to a pseudo load generation circuit that can be set to any value, and the data is read out. By judging whether the data is written data or not, a life detecting method for determining the life of the backup battery is obtained.

According to the present invention, the life of the backup battery is determined by changing the load setting of the pseudo load generating circuit and reading the check data under a plurality of conditions. A life detection method is obtained.

Further, according to the present invention, in the event of an abnormality, a data storage memory RAM can be used with a backup battery.
In a system for backing up a backup battery, a backup battery life detecting device is provided, which is provided with a pseudo load generating circuit for detecting the life of the backup battery.

Further, according to the present invention, the load setting for the pseudo load generating circuit is arbitrarily instructed from the central processing unit CPU, and the backup battery life detecting device data according to claim 3, wherein For each block,
A method of detecting the life of the backup battery, characterized by having a data storage memory RAM having an area configuration having a plurality of check data areas.

Further, according to the present invention, there is provided a backup battery life detecting device according to claim 3, wherein a plurality of backup batteries are provided for backing up the data storage memory RAM when an abnormality occurs.

Further, according to the present invention, there is provided the backup battery life detecting device having a data storage memory RAM having an area configuration in which a plurality of check data areas are provided for each data block. .

Further, according to the present invention, a memory RAM for storing data backed up by a backup battery in the event of an abnormality is provided, and the load of the battery is reduced by a central processing unit in order to evaluate the performance of the backup battery. In a system having a pseudo load generating circuit arbitrarily set from the CPU, at power-on and during steady operation, the battery life is determined by detecting the battery voltage according to the load of the pseudo load generating circuit. Thus, a method for detecting the life of a backup battery is obtained.

Further, according to the present invention, a memory RAM for storing data backed up by a backup battery in the event of an abnormality is provided, and the load of the battery is transferred to a central processing unit for evaluating the performance of the backup battery. In a system having a pseudo load generating circuit arbitrarily set by a CPU, a system having a battery voltage drop detecting circuit for detecting a battery voltage according to a load of the pseudo load generating circuit at the time of power-on and in a steady operation. A backup battery life detecting device characterized by the following features.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described below with reference to the drawings. FIG. 1 will be described first.

FIG. 1 is a block diagram showing the principle of a system according to the present invention. A data storage RAM 1 and a CPU (central processing unit) 2 are connected via a data bus 3. The CPU 2 controls writing and reading of data to and from the RAM 1. In the present invention, in particular,
In order to evaluate the performance of the backup battery described later, it has a function of arbitrarily setting the load of the battery, and data corresponding to several types of pseudo loads (FIG. 3 described later) is stored in advance.

The voltage V1 of the system power supply is supplied to the data storage RAM 1 via the diode D1 when the switch S1 is turned on, and the voltage V2 from the backup battery 4 is supplied when the switch S2 is turned on. RA through a generating circuit (described later) and a diode D2.
It is configured to be supplied to M1.

That is, the switch S2 is turned on at the time of power failure and turned off at the time of power recovery, so that the voltage V2 from the battery 4 is supplied to the RAM 1 only at the time of power failure.

The backup voltage V2 is generally lower than the voltage V1 of the system power supply, and need only be a value sufficient to hold the contents of the RAM1.

Reference numeral 5 denotes the above-mentioned pseudo load generating circuit which generates a voltage change of the battery 4 by changing the resistance value. The pseudo load set in the pseudo load generating circuit 5 is designated by the CPU 2.

It is to be noted that the system configuration is such that there is no pseudo load during a power failure irrespective of a load setting instruction from the CPU 2.

The setting of the pseudo load is, for example, about 1.0 times, 1.1 times, 1.2 times, 1.5 times and 1.5 times the steady load.
As a pseudo load, a method in which one or more magnifications are fixed in advance and a method in which one or more magnifications are fixed from the CPU, or a method in which the magnification can be arbitrarily changed to, for example, 1 to 2 times is adopted.

In the system having such a configuration, when the apparatus is in a state where it is operating steadily online, the switch S2 is off, the switch S1 is on, and the system power supply is turned off. The voltage V1 is supplied via a diode D1 to a system consisting of RAM1 and CPU2. In this steady state, for a predetermined period,
For example, the life of the battery 4 is checked every week or every month.

In order to do this, the load data set in advance from the CPU 2 is generated in the pseudo load generating circuit 5, and the use time of the battery 4 is calculated by the CPU 2 with respect to the voltage fluctuation value due to the pseudo load. The life time of the battery 4 is also calculated, and the calculated result is warned visually or by voice on a display device (not shown).

If the voltage fluctuation value with respect to the dummy load is 1.2 V
When the result of the calculation by the CPU 2 is "the battery has reached the end of its life", it is checked whether or not the contents of the RAM 1 have been destroyed. That is, data is written to and read from RAM1, and if the read data matches the written data, it is determined that the contents of RAM1 have been correctly stored without being destroyed, and conversely, the contents of RAM1 must match. For example, it is determined that the contents of the RAM1 have been destroyed, and correct data is written to the RAM1, and then the operation shifts to a normal operation.

On the other hand, when an abnormal situation such as a power failure occurs, the switch S2 is naturally turned on, the backup voltage V2 is supplied via the dummy generation circuit 5 and the diode D2, and the contents of the RAM 1 are destroyed. Is maintained without

Then, when the abnormal situation is eliminated and the system power supply is restored, a pseudo load instructed by the CPU 2 is generated in the pseudo load generating circuit 5 at the time of the return, as in the case of the above-mentioned steady operation. For the voltage fluctuation value due to the pseudo load, it is further checked whether there is any abnormality in the data stored in the RAM 1 in the same manner as described above.
Next, the battery abnormality and RA in FIG.
The procedure for checking for an M abnormality will be described with reference to FIG.

FIG. 2 is a flowchart for checking whether or not the contents written to and read from the check data area match a predetermined value, depending on the degree of load of the pseudo load generating circuit 5 (FIG. 1). is there.

In FIG. 2, when the power is turned on, that is, when the switch S2 (FIG. 1) is turned off and the switch S3 (FIG. 1) is turned on, the system power supply voltage V1 is supplied to the RAM1 via the diode D1. Is written to the check data area of RAM1 (step
S1). The check data to be written is, for example, a load resistance for a battery test.

Next, in order to evaluate the battery 4 (FIG. 1), a load of a certain value is set by the CPU 2 in the pseudo load generating circuit 5 (FIG. 1) (step S2). At this time, of course, switch S
2 is on, and switch S3 is off.

Next, the data stored in the check data area of the RAM 1 is read, and the CPU 2 checks whether the read data is a predetermined value.
(Step S3).

If the check results match, RA
M1 determines that the load set by the CPU 2 is normal, and if they do not match, it determines that the RAM 1 is abnormal with respect to the set load from the CPU 2.

Here, the evaluation test of the battery 4 is terminated (step S5), or the different load values are sequentially
U2 is set to the pseudo load generating circuit 5 to determine whether to repeat the evaluation of the RAM 1 and the battery 4 (step S2).
Four) .

If it is determined that the operation is to be terminated, the switch S
3 is turned on and the switch S2 is turned off to return to the normal operation (step S7).

Then, the pseudo load generating circuit (
Terminate the pseudo load setting instruction to (Figure 1) (Step S5)
Then, a cycle (step S6) for writing a predetermined value into the check data area of the RAM 1 again is entered and terminated.

Here, the pseudo load set in the pseudo load generating circuit 5 will be described with reference to FIG.

FIG. 3 shows an apparatus using a button battery MR9 made by Toshiba as a backup battery.
5 simulated loads (30 ohm, 60 ohm, 125 ohm,
5 is a graph showing the relationship between battery voltage v and duration h for 300 ohms and 6.5 kohms).

In the figure, the following description will be made on the assumption that a device having a load resistance of 300 ohms has already been used for 6 hours.

The nominal voltage of the button battery MR9 is 1.35V
However, it is assumed that the voltage of the device using the button battery MR9 is 1.2 V or more. According to this assumption, 1.25v
If the battery voltage (including 1.25v) is supplied to RAM1 (FIG. 1), the contents of RAM1 are not destroyed.

Conversely, if a battery voltage of 1.25 V or less is supplied to RAM1, the contents of RAM1 will be destroyed.

Based on the above assumption, the intersection with a load resistance of 300 ohms and a connection time of 6 hours corresponds to 1.25v. Therefore, the content of the RAM 1 is not destroyed because the device voltage is still maintained at 1.2 V or more at present.

However, the life of the button battery with respect to the load resistance of 300 ohms, that is, about 84 hours (= about 90 hours-6 hours) is required after the CPU 2 before the voltage becomes 1.2 V or less.
, And the result of the calculation is warned by visual means or audio means.

Next, when the characteristics shown in FIG. 3 are applied to the battery evaluation test according to the present invention, the load resistance is set to 125 ohms, and the voltage at the intersection of the load resistance of 125 ohms and the connection time of 6 hours (H) is examined. And it is about 1.16v. The voltage at the intersection of the load resistance of 30 ohms and the connection time of 6 hours (H) is about 1.04V.

Therefore, in this case, the load resistance is 60 ohms,
Since both 30 ohms are less than the battery operating voltage of 1.2 volts for a connection time of 6 hours, the contents of RAM1 are destroyed. Here, the CPU calculates, based on the data stored in the RAM1, a life period until the use time of the battery corresponding to the load resistance of 60 ohms and the connection time of 6 hours is reduced to 1.16v, and the calculation result, for example, A central monitoring station (not shown) is notified by means of visual appeal, that is, by displaying on a display device.

Next, another embodiment of the present invention will be described with reference to FIG.
The description will be made based on FIG.

FIG. 4 is a block diagram of a system showing an embodiment according to the present invention. The same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof is omitted.

The difference between the embodiment of FIG. 4 and that of FIG. 1 is that the embodiment of FIG.
In the embodiment of FIG. 4, the battery voltage corresponding to the load of the pseudo load generation circuit 5 is detected by the battery
It is a point to know.

That is, the CPU 2 determines how much the battery voltage has dropped according to the pseudo load set by the CPU 2, and determines the remaining life of the battery 4 based on the falling level. know.

The life of the battery 4 can be checked even in a steady state.

Next, another embodiment of the present invention will be described with reference to FIG.
The description will be made based on FIG.

FIG. 5 is a block diagram of a system showing an embodiment according to the present invention. The same parts as those in FIG.

The embodiment of FIG. 5 differs from that of FIG. 1 in that a memory for diagnosing a battery abnormality is separately provided.

In FIG. 7, reference numeral 7 denotes a data storage memory (RAM) which stores, for example, operation information parameters for operating the system and check data for knowing the life of the backup battery 4. Storage addresses are arranged at one or more locations.

Reference numerals 8 and 9 denote current memory RAMs. Among them, the current memory RAM 9 is a memory for storing various data including check data necessary for diagnosing an abnormality of the battery 4 in a steady operation state. .

The voltage V1 of the system power supply is
7, the voltage V1 of the diode D3 is applied to the RAM7 via the diode D3, and the RAM8 is applied directly to the RAM8.
Further, the RAM 9 is connected to be supplied via a switch 3 and a diode D5, respectively.

When the system power supply fails, the RAM 7
Through the switch S1 and the diode D4.
The RAM 9 is connected via a switch S2, a pseudo load generating circuit 5 and a diode D6 so that the voltage V2 of the battery 4 is supplied to each of them.

Next, the operation of checking the battery voltage V2 and the abnormality of the RAM in the above configuration will be described.

First, the first check, that is, the operation of checking the abnormality of the battery 4 and the abnormality of the RAMs 7 and 9 only when the power is turned on, will be described.

When the power is turned on, it is checked whether the backup operation has been properly maintained until the power is turned on, or if the backup operation has not been maintained, whether the contents of the RAM has been destroyed.

The switches S1 and S2 are turned on and the switch S3 is turned off, and the pseudo load is sequentially set from the CPU 2 to the pseudo load generating circuit 5, and the load value at which the voltage fluctuation due to the pseudo load becomes equal to or less than the steady voltage value of the system. From the battery life. Since this point is the same as that in FIG. 1, the details are omitted.

FIG. 6 shows a third embodiment of the present invention.
The description will be made based on FIG.

FIG. 6 is a block diagram of an apparatus showing an embodiment according to the present invention. The same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 6 shows two backup batteries.
In an embodiment having 4a and 4b, the battery life can be longer than one backup battery, and the battery voltages V2a and V2b are set to switches S4a and S4.
The data is supplied to the RAM 1 via the b.

During normal operation, the switches S4a and S4b are arbitrarily switched according to a command from the CPU 2 to judge the performance of the battery voltages V2a and V2b, and the result is notified.

That is, when the power is turned on, the switches S4a and S4
b are both in the ON state, and the switches S4a and S4b can be independently and arbitrarily switched according to an instruction from the CPU 2 during steady operation.

On the other hand, when the power is turned off, both switches S4a and S4b are turned on regardless of the contents of the instruction from CPU2.

Therefore, when the power is turned on or the power is turned off, since both the switches S4a and S4b are on, either the battery voltage V2a or V2b is supplied to the RAM1 from either the battery 4a or S4b. .

That is, since the backup battery voltage can be supplied from one of the two batteries instead of one battery, it can be said that the embodiment is highly reliable.

In the steady state, the switch S4a or S4b is arbitrarily switched to change the battery voltage V2a or V2b.
Are checked separately, and the life expectancy can be estimated for each battery. As a result, the battery replacement is naturally performed sequentially from the end of the life, thereby increasing the reliability of the system.

Here, the area configuration of the RAM 1 is shown in FIG.
This will be described with reference to FIG.

FIGS. 7 and 8 are internal configuration diagrams showing the data storage state of the RAM1, and will be described first with reference to FIG.

FIG. 7 shows an embodiment in which one check data area is provided for each data block. In this embodiment, only one rank of data can be checked in data block units.

FIG. 8 shows another embodiment of the RAM structure in which the number of check data areas provided for each data block differs.

In a data block having a large number of checks, for example, in a RAMn space, three types of pattern checks are possible, and the check accuracy is improved accordingly.

That is, since there is variation in the RAM, checking is performed in several patterns to prevent a check error due to variation in the RAM.

[0078]

According to the present invention described above, the life of the backup battery 4 can be increased in real time by providing the pseudo load generation circuit 5 and detecting the voltage fluctuation based on the load set in this circuit. It is possible to know in advance, so that remote maintenance can be performed even in the case of a remote monitoring control device at a remote location, and even if a sudden abnormal situation occurs, malfunction of the device due to destruction of RAM contents can be completely prevented. .

Further, according to the present invention, by providing a plurality of backup batteries, the reliability of the system can be further improved.

According to the present invention, by providing a plurality of check data areas for each data block, RA
Check errors due to variations in M can be prevented,
As a result, the checking accuracy of the RAM can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram of a backup battery life detecting device according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a check procedure for detecting an abnormality in a battery and a data storage memory RAM according to the present invention.

FIG. 3 is a line graph showing a relationship between voltage fluctuation and time with respect to a pseudo load value according to the present invention.

FIG. 4 is a block diagram of a system illustrating an embodiment according to the present invention.

FIG. 5 is a block diagram of a system showing another embodiment according to the present invention.

FIG. 6 is a block diagram of a system showing another embodiment according to the present invention.

FIG. 7 is a block diagram showing an area configuration of a data storage memory RAM used in the system of the present invention.

FIG. 8 is a block diagram showing another area configuration of the data storage memory RAM used in the system of the present invention.

FIG. 9 is a block diagram showing a conventional backup battery abnormality detection system.

[Explanation of symbols]

1. Memory for data storage (RAM) 2. Central processing unit (CPU) 3. Data bus 4. Battery for backup 5. Backup battery 5. ... Pseudo load generation circuit 6... Battery voltage drop detection circuit 7, 8... Battery backup memory (RAM) 8, 9... Current memory (RAM) 10. Data storage memory (RAM) 11 Diode 12 Backup battery V1 System power supply voltage V2 Backup battery voltage V2a , V2b… Backup battery voltage S1 to S3 Switches S4a to S4b Switches D1 to D6 Diodes

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI H02J 9/00 G06F 1/00 341X

Claims (8)

[Claims] 1. In a system for backing up a data storage memory RAM with a backup battery in the event of an abnormality, it is possible to arbitrarily disable the backup battery after writing check data in the data storage memory. A method for detecting the life of a backup battery, comprising connecting a pseudo load generating circuit, reading the data, and determining whether the value is data written in advance to determine the life. 2. The life of the backup battery according to claim 1, wherein the life of the backup battery is determined by changing the load setting of the pseudo load generation circuit and reading the check data under a plurality of conditions. Detection method. 3. A backup system for backing up a data storage memory RAM with a backup battery when an abnormality occurs, wherein a backup load generating circuit for detecting the life of the backup battery is provided. Battery life detector. 4. The backup battery life detecting device according to claim 3, wherein a load setting for the pseudo load generating circuit is arbitrarily instructed from a central processing unit CPU. 5. The backup battery life detecting device according to claim 3, wherein a plurality of backup batteries are provided for backing up the data storage memory RAM when an abnormality occurs. 6. The backup battery life detecting device according to claim 3, further comprising a data storage memory RAM having an area configuration in which a plurality of check data areas are provided for each data block. 7. A memory RAM for storing data backed up by a backup battery when an abnormality occurs,
In addition, in order to evaluate the performance of the backup battery, in a system having a pseudo load generating circuit which is arbitrarily set by using the load of this battery from the central processing unit CPU,
A method for detecting the life of a backup battery, comprising detecting a battery voltage according to a load of the pseudo load generating circuit at power-on and during a steady operation. 8. A memory RAM for storing data backed up by a backup battery when an abnormality occurs,
In addition, in order to evaluate the performance of the backup battery, in a system having a pseudo load generating circuit which is arbitrarily set by using the load of this battery from the central processing unit CPU,
A backup battery life detecting device comprising a battery voltage drop detecting circuit for detecting a battery voltage according to a load of the pseudo load generating circuit at the time of power-on and during a steady operation.