JPH08272489A - Battery backup method - Google Patents

Abstract

PURPOSE: To improve the availability factor in a service interruption mode through the effective use of a battery and also to surely stop an operation state when a power supply is cut. CONSTITUTION: The power is usually supplied to a main processor 4 and an auxiliary processor 5 from an AC power supply 1 via a power supply controller 3. When the power supply 1 is cut, a battery 2 substitutes for the power supply 1. When the power is supplied from the battery 2, the processor 5 periodically reads the battery discharge current data 32 via a current measurement circuit 11 and an A/D conversion circuit 12 to monitor the remaining capacity of the battery 2. When the battery remaining capacity is reduced less than the prescribed value, the processor 5 instructs the processor 4 to start the shutdown processing. When the end of the shutdown processing is notified from the processor 4, the processor 5 instructs a power supply control circuit 13 to cut the power supply by means of a power supply ON/OFF signal 33.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery backup method for supplying power from a battery when a commercial power supply is interrupted, for a device and a system (hereinafter, collectively referred to as a device) that requires an operation stop process when the power is cut off. In particular, a battery that effectively uses the battery to reduce the operation stop time at the time of power failure, improves the operation rate, reliably performs the operation stop processing of the device, and prevents the deterioration of the capacity characteristic due to the over discharge of the battery. Regarding backup method.

[0002]

2. Description of the Related Art In a computer or the like, when the power is turned off, it is common to perform a predetermined operation stop process (shutdown process) such as saving data to an external storage device before turning off the power. In this type of device, when processing is performed by power supply from the battery when the commercial power supply is cut off, the remaining battery capacity is set to a specified value in order to prevent deterioration of capacity characteristics and failure due to over discharge of the battery. If reached
It is necessary to immediately stop the operation and stop the power supply from the battery.

Conventionally, the simplest method is to monitor the output voltage of the battery when power is supplied from the battery, and if it falls below a predetermined value, perform an operation stop process and disconnect the battery power supply. It has been known. Further, for example, as described in Japanese Patent Laid-Open No. 6-51871, in a computer system equipped with an uninterruptible power supply, the output voltage of the battery in the uninterruptible power supply is reduced by a predetermined ratio from the rated value. The method of measuring the time and notifying it to the computer, calculating the battery holding time from the notified time measurement value and storing it, and executing the computer normal stop processing of the processing time corresponding to the battery holding time at the time of power failure is is there.

[0004]

In the method of simply monitoring the output voltage of the battery when power is supplied from the battery, when the load temporarily increases and the output voltage falls below a predetermined value, the battery capacity has a margin. Even if there is, the operation stop process is started, and there is a problem in effective use of the battery.

Further, according to the method disclosed in Japanese Patent Laid-Open No. 6-51871, the measurement process and the actual stop process are performed between the battery holding time during measurement and the battery holding time during actual power failure. When the battery holding time is different due to the load variation due to the different procedure, there is a problem that the battery capacity cannot be effectively used or the battery is exhausted and the stop process cannot be completed. In addition, this method is effective only when a power failure occurs with the battery fully charged, and in the case of repeated power failure and recovery from power failure, the battery will be exhausted before the stored battery retention time elapses. However, there is a problem that the stop process cannot be completed, and in order to avoid this, if the system is stopped even with a temporary power failure, there remains a problem that the operating rate of the system decreases.

An object of the present invention is to use the battery more effectively in accordance with the actual state of battery consumption at the time of a power failure to safely stop the system, and to maintain the remaining battery capacity which is less than the full charge in the intermittent power failure. It is to improve the operating rate at the time of power failure according to the battery capacity by accurately grasping the above, and based on this, deciding whether or not to stop the system in real time, including temporary power failure.

[0007]

SUMMARY OF THE INVENTION The invention of claim 1 is intended for an apparatus that needs to be shut down after the operation is stopped when the power is turned off. In the battery backup method that supplies power from the battery during a power outage, when supplying power from the battery,
By periodically reading the discharge current amount of the battery to obtain the total consumed electric capacity of the battery or the remaining battery capacity from the time of the occurrence of the power failure, and when the total consumed electric capacity of the battery or the remaining battery capacity reaches a predetermined value, the device Is instructed to start the operation stop processing, and the supply of power from the battery is stopped when the operation stop processing of the apparatus ends.

According to the second aspect of the present invention, when the power is supplied from the commercial power source, the total consumed electric capacity of the battery or the remaining battery capacity obtained during the power failure is corrected at regular time intervals by the electric capacity charged at the constant time. It is characterized by

According to a third aspect of the present invention, when power is supplied from the commercial power source, a pseudo power failure is generated, the current supply from the battery is switched to the current supply from the battery, the operation stop processing is tried, and the electric capacity consumed in the operation stop processing. Is actually measured, and the measured value is used as a standard of the allowable battery capacity when actually instructing the device to start the operation stop process.

According to the invention of claim 4, when the commercial power supply is switched from the power failure to the energized state and the power failure is detected within the specified time, it is recognized that the power failure is recovered, and the power failure is detected again within the specified time. If it does, it is recognized that the power outage is continuing.

According to the invention of claim 5, when the recovery of the power failure is recognized prior to instructing the apparatus to start the operation stop processing, the operation stop processing start instruction is stopped and the apparatus is instructed to start the operation stop processing. When the recovery of the power outage is recognized later, it is characterized that the operation restart is instructed again.

[0012]

[Function] The power supply / power failure of the commercial power source is constantly monitored, and when the power failure occurs, the power is immediately switched from the battery to continue the operation of the device. When power is supplied from this battery, the amount of battery discharge current is read periodically, and this is cumulatively added to calculate the total electric capacity consumed from the time of power failure occurrence to each reading time as an approximate value of the current time integration. The battery remaining capacity is obtained by subtracting the total consumed electric capacity from the battery capacity when fully charged. When the remaining battery capacity reaches the capacity of the battery required to execute the operation stop processing, plus the spare capacity and the capacity left to prevent over-discharge, the operation stop processing start time is set, and a power failure occurs to the equipment. To start the operation stop process. The trigger for starting the operation stop process may be based on the total electric power consumption of the battery from the time of occurrence of the power failure.

When the recovery of the power failure is recognized after the instruction to start the operation stop processing, the apparatus is instructed to restart the operation by the recovery of the power failure. When the device receives the operation stop processing start instruction, the apparatus executes the operation stop processing, and powers off the battery after the operation stop processing is completed. Further, when the device receives the operation restart instruction during execution of the operation stop processing, the apparatus executes the operation restart processing after the operation stop processing is interrupted or once ended.

On the other hand, while the commercial power source is in the energized state, the total consumed electric capacity is calculated by subtracting the electric capacity charged during the fixed time from the total consumed electric capacity calculated during the power failure at regular intervals. To continue.

By such an operation, even in a device which requires an operation stop process when the power is cut off, the power supply can be surely executed at the time of a power failure and the power is cut off while leaving the battery capacity for preventing overdischarge. Even after the operation stop processing is started, the operation can be restarted if the power failure is recovered before the power is cut off. Further, by continuing to calculate the total battery consumed electric capacity even when the power is supplied, it is possible to accurately grasp the remaining battery capacity even when the battery is stopped.

[0016]

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

FIG. 1 is a block diagram showing an embodiment of an apparatus to which the battery backup method of the present invention is applied.
In the figure, 1 is an AC power supply (commercial power supply), 2 is a battery, 3 is a power supply control device, 4 is a main processing device, 5 is an auxiliary processing device, 6 is a shared memory of both processing devices 4, 5, and 7 is a main processing device. A display device connected to the device 4. Power control device 3
Is an AC / DC conversion circuit 10 for converting AC of the AC power supply 1 into DC, a current measuring circuit 12 for measuring the amount of discharge current from the battery 2, and switching of power supply from the AC power supply 1 and the battery 2, It is composed of a power supply control circuit 13 that controls power supply to the processing device 4 and the auxiliary processing device 5. Further, the power supply control circuit 13 includes an energization detection unit 131 that detects energization and power failure states of the AC power supply 1, a charging completion detection unit 132 that detects completion of charging of the battery 2, and a power supply switching that switches between the AC power supply 1 and the battery 2. Main power supply unit 1 that supplies electric power to the unit 133 and the main processing unit 4 via the main power supply line 20.
34, an auxiliary power supply unit 135 that supplies power to the auxiliary processing device 5 via the auxiliary power line 21.

Signals and data between the power supply control device 3 and the auxiliary processing device 5 include the energization detecting portion 131 of the power supply control circuit 13 to the auxiliary processing device 5 so that the AC power supply 1 is energized or a power failure is transmitted. Status signal 30 and power supply control circuit 1
Battery charge completion signal 3 for transmitting the completion of charging of the battery 2 from the charge completion detecting unit 132 of 3 to the auxiliary processing device 5.
1, a discharge current data signal 32 for transmitting digital conversion data of a discharge current value from the A / D conversion circuit 12 to the auxiliary processing device 5, and the main power supply line from the auxiliary processing device 5 to the main power supply unit 134 of the power supply control circuit 13. There is a power on / off signal 33 for instructing to turn on / off 20. The power on / off signal 33 is also given to the power switching unit 133, and the power switching unit 1
When the signal 33 receives the signal 33, it uniquely switches to the AC power supply 1.

Signals between the auxiliary processing device 5 and the main processing device 4 include an interrupt signal 41 from the auxiliary processing device 5 to the main processing device 4 and an interrupt signal 42 from the main processing device 4 to the auxiliary processing device 5. There is. The shared memory 6 can be read and written by both the auxiliary processing device 5 and the main processing device 4. The main processing unit 4 can read the data in the shared memory 6 and display it on the display unit 7.

When the system is started up, the power supply control device 3 is operated by the power supply from the AC power supply 1, and at the same time, the auxiliary processing device 5 is operated by being supplied with power by the auxiliary power supply part 135 through the auxiliary power supply line 21. To do. When the auxiliary processing device 5 uses the power-on / off signal 33 to instruct the main power supply part 134 to turn on the power, the main power supply part 134 turns on the main power line 20 of the main processing device 4. In this way, power is normally supplied from the AC power supply 1 to the main processing device 4 and the auxiliary processing device 5 through the power supply control device 3. At this time, the battery 2 is also charged, and when the charging is completed (fully charged), the battery charging completion signal 31 is transmitted from the charging completion detection unit 132 to the auxiliary processing device 5.
Completion of charging is detected, for example, when the charging current becomes a predetermined value or less.

In FIG. 1, AC power supply 1-AC / DC conversion circuit 10-energization detector 131-charge completion detector 13
It is supposed that the battery 2 will be charged through the route of 2.
The AC / DC conversion circuit 10 does not require the energization detection unit 131.
The output side of may be branched directly to the charging completion detecting unit 132.

When a power failure occurs in the AC power supply 1 and the output voltage of the AC / DC conversion circuit 10 becomes a predetermined value or less, the energization detection unit 131 sends an energization state signal 30 to the auxiliary processing device
A power failure detection signal is transmitted to the power source switching section 133 and a power source switching section 133 issues a signal 34 for switching to the battery side. Upon receiving this switching signal 34, the power source switching unit 133 switches from the battery 2 to power feeding. The discharge current amount of the battery 2 is measured by the current measuring circuit 11, and the A / D conversion circuit 12 converts this into digital data, and the discharge current data signal 3
2 is transmitted to the auxiliary processing device 5.

The auxiliary processing device 5 is always provided with the energization state signal 3
When 0 is monitored and a power failure is detected, the discharge current data signal 32 (battery discharge current amount) is periodically read, and cumulative addition is performed to calculate the total electric capacity consumed from the time of the power failure occurrence,
The remaining battery capacity is obtained by subtracting the total consumed electric capacity from the battery capacity when the battery is fully charged. And
When the remaining battery capacity reaches a predetermined value, an interrupt 41 for starting the operation stop processing is issued to the main processing unit 4. In response to this, the main processing device 4 executes a predetermined operation stop process, and when the operation is ended, returns an operation stop process end interrupt 42 to the auxiliary processing device 5. When confirming the end of the operation stop processing of the main processing unit 4, the auxiliary processing unit 5 instructs the main power supply unit 134 to turn off the power by using the power-on / off signal 33, whereby the main power supply unit 134 is instructed. The main power line 20 is cut off. The power on / off signal 33 is also given to the power source switching unit 133, and the power source switching unit 133 switches from the battery 2 to the AC power source 1. As a result, the battery 2 for both the main processor 4 and the auxiliary processor 5
Since the power supply from the battery is cut off, the deterioration of the capacity characteristic due to the over-discharge of the battery 2 can be prevented. Since the power supply switching unit 133 is on the AC power supply 1 side, when the power failure is restored, the operation of the auxiliary processing device 5 is also restored.

When the main power supply line 20 is turned on by the power supply from the AC power supply 1, the auxiliary processing device 5 uses the power on / off signal 33 to supply power to the main power supply unit 134 of the power control circuit 13. When the disconnection is instructed, only the power supply to the main processing unit 4 is disconnected.

The operation example of the battery backup of the present invention in the configuration of FIG. 1 will be described in detail below with reference to the flowcharts of FIGS.

The auxiliary processing device 5 periodically performs the processing shown in FIG. That is, the auxiliary processing device 5 periodically sends the energization state signal 3
When 0 is read and a power failure is detected (YES in step 201), the digital conversion data of the battery discharge current value is read from the discharge current data signal 32 (step 2).
11), this is cumulatively added for each loop to obtain the total consumed electric capacity up to the loop (current time) (step 21).
2). This total consumed electric capacity is written in the shared memory 6 to be used for displaying the total consumed electric capacity by actually measuring the battery capacity required for the shutdown processing (operation stop processing) (step 213). Then, the total electric capacity consumed up to the loop is subtracted from the battery capacity when the battery is fully charged, and this is taken as the remaining battery capacity (step 21).
4). If the remaining battery capacity is less than or equal to the shutdown start trigger capacity (step 215) and the shutdown start instruction has not been issued (step 216), after writing the shutdown start instruction due to the power failure to the shared memory 6 (step 217), the main The interrupt 41 is issued to the processor 4 (step 218). Note that the shutdown start trigger capacity may be, for example, a value obtained by adding the reserve capacity and the battery capacity left for preventing overdischarge to the battery capacity required for shutdown. A method of actually measuring the battery capacity required for this shutdown will be described later. Further, the shutdown start timing may be based on the total consumed electric capacity instead of the remaining battery capacity.

On the other hand, the auxiliary processing device 5 uses the energization state signal 3
When 0 is read and energization is detected (NO in step 201), first, it is determined whether a power failure has been detected in the past within a specified time (step 202). When the power failure is not detected within the specified time (NO in step 202), that is, when the energization is continued, the battery charge completion signal 3 is immediately output.
If 1 is not read and the battery is not fully charged (NO in step 207), the electric capacity charged during the certain time (same as the cycle of the stop monitoring process) is subtracted from the total consumed electric capacity calculated up to that point. (Step 209) to set a new total electricity consumption. If the battery is fully charged (YES in step 207), the total consumed electric capacity is initialized (cleared to 0) (step 208), and the cumulative error of the total consumed electric capacity calculated during the power failure and the charging due to energization is eliminated. . Then, the newly calculated total consumed electric capacity is written in the shared memory 6 (step 210). It should be noted that the charging electric capacity is changed so that the configuration of FIG. 1 is changed through the current measuring circuit 11 even in the case of battery charging, and a current measuring circuit 11 capable of measuring a bidirectional current is used. Conversion circuit 12
The actual charging current amount of the battery 2 may be read by.

In the past, a power failure was detected within a specified time (YES in step 202), but after that, energization was continuously detected, and if the specified time has elapsed (Y in step 203).
ES), recognize that the power failure has recovered. In this case, after the shutdown start instruction has been issued due to a past power failure and the power failure recovery notification has not been issued (step 204), after writing the shared memory 6 power failure recovery notification (step 205), the main processing An interrupt 41 is issued to the device 4 (step 206). If the shutdown start instruction due to the past power outage has not been issued, or if the power outage recovery notification has already been issued, step 20
Skip 5,206. The subsequent processing is the same as when the energization is continuing (steps 207 to 210).

If a power failure has been detected within a specified time in the past and the energization has not been continuously detected for a specified time (NO in step 203), the recovery from the power failure is not recognized and the power failure is occurring. Continue to recognize what is. This is to prevent the power failure recovery notification from being issued when the energization is temporarily erroneously detected or when the power supply is unstable. In this case as well, since energization was detected anyway,
The processing of steps 207 to 210 is performed.

FIG. 3 is a flow chart of processing by the interrupt 41 of the main processing unit 4, and FIG. 4 is a flow chart of monitoring completion of shutdown processing due to power failure of the main processing unit 4.

When the main processing unit 4 detects a shutdown start instruction due to a power failure based on the contents of the interrupt 41 and the shared memory 6 (step 301 in FIG. 3), it starts the shutdown processing (step 302). Then, the shutdown process is completed (step 401 in FIG. 4),
If there is still a power outage at that time (step 402
No), the power-off instruction is written in the shared memory 6 (step 403), and then the interrupt 42 is issued to the auxiliary processing device 4 (step 404).

When the main processor 4 receives the interruption 41 again while detecting the shutdown start instruction due to the power failure and executing the shutdown processing, and detects the power failure recovery notification according to the contents of the shared memory 6 (see FIG. 3). In step 303, the shutdown process is continued (step 304), and after the shutdown process is completed, it is determined that the power failure is recovered (YE in step 402).
S), reset the main processor 4 by itself (step 40
5), restart. However, if a shutdown start instruction due to a power failure is detected again by the interrupt 41 and the shared memory 6 while detecting the power failure recovery notification and continuing the shutdown processing (step 301 in FIG. 3), the shutdown processing is continued (step 302) and when the shutdown process is completed (step 40 in FIG. 4).
1) Then, it is determined that the power is in a power failure state (NO in step 402), the power-off instruction is written in the shared memory 6 (step 403), and then the interrupt is issued to the auxiliary processing device 5 (step 404).

FIG. 5 is a flow chart of processing by the interrupt 42 of the auxiliary processing device 5. When the auxiliary processing device 5 detects a power-off instruction based on the contents of the interrupt 42 and the shared memory 6 (step 501), the power-on / off signal 33 turns off the power to the main power supply unit 134 of the power control circuit 13. Instruct (step 502). As a result, the main power supply unit 134 shuts off the main power line 20.
The power-on / off signal 33 is also given to the power source switching unit 133, and the power source switching unit 133 switches to the AC power source side, so that the power supply from the battery 2 to the auxiliary processing device 5 is also cut off.

Next, a method for actually measuring the battery capacity required for the shutdown process, that is, the operation stop process will be described. At the trial adjustment stage, the auxiliary processing device 5 at least periodically executes a process of calculating the total electric capacity of the battery 2 and setting it in the shared memory 6, and the main processing device 4 sets the auxiliary processing device 5 in the shared memory 6. The total electric capacity consumed is always output to the display device 7 for external display. In this configuration, the AC power supply 1 is shut off to generate a pseudo power failure, and at the same time, the shutdown process is tried, and the total consumed electric capacity displayed on the display device 7 at the end of the shutdown process is used as the battery required for the shutdown. Use the actual measured value of the capacity. If the shutdown execution time is variable, it may be tried under the condition that the execution time is the maximum.

[0035]

According to the battery backup method of the present invention, the following effects can be achieved. (1) In a device that needs to be shut down (shutdown process) after shutting down the power when the power is turned off, the battery capacity required for shutdown and the battery capacity left to prevent over-discharge are secured and the shutdown processing is started. By doing so, it is possible to reliably execute the shutdown process, prevent the battery from being over-discharged, and maintain the life of the battery. For example, in the case of a system that performs communication by connecting this type of processing device to a processing device at a remote place, if the processing device at the remote place is notified that the processing device will shut down due to a power failure during the shutdown process, the cause is unknown. It is possible to prevent the communication from being interrupted.

(2) While the power is on, at regular intervals,
Accurate determination of the remaining battery capacity even during intermittent power outages by continuing to calculate the total consumed electric capacity by subtracting the electric capacity charged during the fixed time from the total consumed electric capacity calculated during the power outage. it can.

(3) Execution of the actual shutdown process by artificially generating a power failure, attempting the shutdown process, and displaying the total consumed electric capacity by an external display means or the like at the end of the shutdown process. You can accurately grasp the battery capacity required for.

(4) When the power failure is detected again within the specified time after the energization is detected, by continuing to recognize that the power failure is occurring without recognizing the recovery of the power failure,
Reliability can be improved because it is possible to prevent erroneous recognition of power failure recovery when power is temporarily erroneously detected or when power supply is unstable.

(5) Even after a power failure, the shutdown processing is not started until the remaining battery capacity reaches the shutdown start trigger capacity, and if the power failure is restored before the shutdown is started, the shutdown processing is not performed.
In the case of a temporary power failure within the allowable range of battery capacity, it is not necessary to stop the operation, and the operating rate at the time of power failure is improved.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration example of a processing device for carrying out a battery backup method of the present invention.

FIG. 2 is a flowchart of a power failure monitoring process of an auxiliary processing device.

FIG. 3 is a flowchart of a process by interruption of a main processing unit.

FIG. 4 is a flowchart of processing for monitoring completion of shutdown processing due to a power failure of the main processing device.

FIG. 5 is a flowchart of processing by an interrupt of the auxiliary processing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 AC power supply 2 Battery 3 Power supply control device 4 Main processing device 5 Auxiliary processing device 6 Shared memory 7 Display device 10 AC / DC conversion circuit 11 Power supply measurement circuit 12 A / D conversion circuit 13 Power supply control circuit 131 Power detection unit 132 Charging completion Detection unit 133 Power switching unit 134 Main power supply unit 135 Auxiliary power supply unit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masashi Miyauchi 810 Shimoimaizumi, Ebina-shi, Kanagawa Hitachi Ltd. Office Systems Division (72) Inventor Kazuo Morita 810 Shimoimazumi, Ebina-shi, Kanagawa Hitachi, Ltd. (72) Inventor Atsuo Kobayashi 1 Horiyamashita, Hadano City, Kanagawa Prefecture Hitachi Computer Engineering Co., Ltd.

Claims (5)

[Claims] 1. A battery backup method in which power is normally supplied from a commercial power source, and power is supplied from a battery when the commercial power source is interrupted, for a device that needs to be shut down when the power is turned off. When power is supplied from the battery, the discharge current amount of the battery is periodically read to obtain the total battery capacity consumed or the remaining battery capacity from the time of the power failure, and the total battery consumed capacity or the remaining battery capacity is a predetermined value. When the above condition is reached, the device is instructed to start the operation stop process, and the power supply from the battery is stopped when the operation stop process of the device is completed. 2. The battery backup method according to claim 1, wherein when power is supplied from a commercial power source, at regular intervals.
A battery backup method, characterized in that the total battery consumed electric capacity or the remaining battery capacity obtained during a power outage is corrected by the electric capacity charged in the fixed time. 3. The battery backup method according to claim 1, wherein when power is supplied from a commercial power source, a pseudo power failure is generated to switch to power supply from a battery, an operation stop process is tried, and the operation is stopped. A battery backup method characterized by actually measuring an electric capacity consumed in a process and using the measured value as a standard of a battery allowable capacity when actually instructing a device to start an operation stop process. 4. The battery backup method according to any one of claims 1 to 3, wherein after the commercial power supply is turned on from a power failure, it is recognized that the power failure is recovered when the power failure is not detected within a specified time, A battery backup method characterized in that if a power failure is detected again within the time, the power failure is recognized as continuing. 5. The battery backup method according to claim 4, wherein when power recovery from the battery is recognized and recovery of power failure is recognized prior to instructing the apparatus to start operation stop processing, the operation stop processing start instruction is canceled. A battery backup method is characterized in that when the device is instructed to start the operation stop processing and then recognizes the recovery from the power failure, it is instructed to restart the operation again.