JP4717856B2 - Battery system, battery system control method, battery system control program, and program recording medium - Google Patents

Description

  The present invention relates to a battery system, a battery system control method, a battery system control program, and a program recording medium, and in particular, a battery system that supplies power output from a battery to a load, a battery system control method, a battery system control program, and a program recording medium. About.

  Nickel metal hydride storage batteries used for DC power supplies are characterized by higher energy density, less battery life and less burden on the environment than lead storage batteries, and are small and lightweight, making them easy to carry Therefore, in recent years, it has been rapidly spreading as an in-vehicle battery and a disaster countermeasure power source.

  When using a nickel metal hydride storage battery as a power source, for example, a single nickel hydride storage battery called a single cell (rated voltage 1.2 V, current capacity 95 Ah) connected in series with k (for example, 10) one unit (hereinafter referred to as “unit”) 1 module), and this module connected in m units (for example, 4 units) in series and / or in parallel is used as an assembled battery, and n sets (for example, 3 sets) of assembled batteries are connected in parallel. A large capacity nickel-metal hydride storage battery system is configured by connection.

  In such a large-capacity battery system, various proposals have also been made regarding a mechanism for managing the power supply capacity supplied to the load. For example, Japanese Patent Application Laid-Open No. 2004-119112 “Power Supply Device” in Patent Document 1, Japanese Patent Application Laid-Open No. 2004-120856 “Power Supply Device”, or Japanese Patent Application Laid-Open No. 2004-120857 “Power Supply Device” in Patent Document 3. Describes a management method in a power supply system including a plurality of assembled batteries connected in parallel, a charge control unit, and a discharge control unit.

  In Patent Document 1, in order to facilitate the estimation of the life of the assembled battery at the time of maintenance / inspection, the manufacturing date of the assembled battery is stored inside, and a predetermined date is determined based on the stored manufacturing date of the assembled battery. It describes that a usable period in which power can be supplied is calculated and a battery pack replacement date is displayed.

  Further, in Patent Document 2, even if a power failure or the like occurs during the execution of a discharge capacity test for determining the deterioration of an assembled battery, a certain set of deterioration determination targets is provided to enable power supply to the load side. Battery monitoring means for performing a discharge capacity test not only when the battery pack is charged to full charge but also when a battery pack that is not subject to deterioration determination is charged to full charge when performing a battery discharge capacity test It is described to provide.

Further, in Patent Document 3, in order to level the power demand and reduce the power cost, it is monitored whether or not the remaining capacity of the assembled battery is equal to or lower than the charging start threshold value, and is set to be equal to or lower than the charging start threshold value. In this case, it is described that a battery monitoring unit is provided that waits for a predetermined time in the middle of the night when power usage is low and starts supplementary charging of the assembled battery.
JP 2004-119112 A JP 2004-120856 A JP 2004-120857 A

  By combining the storage battery, the discharger, and the charger, it is possible to configure a backup power supply system for operating the load device even when a commercial power supply fails. In such a power supply system, for example, as shown in FIG. 5, an assembled battery 1 in which a plurality of nickel hydride storage batteries are connected in series and / or in parallel, and a bypass circuit 10 that bypasses AC power from an AC input 5. And a charger 6 that converts AC power into DC power to charge each nickel metal hydride storage battery, that is, the assembled battery 1, an inverter 7 that converts power output from the assembled battery 1 into AC power, and a switch 8. .

  When the AC power from the AC input 5 is valid, the switch 8 connects the bypass circuit 10 to the AC load 9 and the input AC power is output to the AC load 9 as it is. Furthermore, the assembled battery 1 is charged via the charger 6 with AC power from the AC input 5. On the other hand, at the time of a power failure in which the AC power from the AC input 5 becomes invalid, the switch 8 connects the output of the inverter 7 to the AC load 9, and the energy output from the assembled battery 1 is AC via the inverter 7. It is converted into electric power and supplied to the AC load 9.

  The control unit 4 monitors the state of the assembled battery 1 in order to ensure the safety of the assembled battery 1 and prevent battery deterioration, and detects full charge during charging, failure detection of the assembled battery 1, and the inverter 7. Has the function of performing the operation control. Further, since the operation of the control unit 4 requires a power source, and it is necessary to continue the control by the control unit 4 even when the AC power from the AC input 5 is interrupted, the operation to the control unit 4 Power is supplied from the assembled battery 1.

  In general, the storage battery constituting the assembled battery 1 has reached the discharge end voltage by the operation of the control unit 4 because the deterioration proceeds when the discharge continues below the discharge end voltage predetermined as the storage battery. It is necessary to stop the discharge of the assembled battery 1 at the time. Therefore, when the AC power of the AC input 5 is supplying power from the assembled battery 1 to the AC load 9 during a power failure, the control unit 4 monitors the output voltage of the assembled battery 1 and determines a predetermined voltage threshold, that is, discharge. When the voltage drops below the final voltage, control is performed to stop the operation of the inverter 7 and stop the power supply to the AC load 9.

  However, since the power of the assembled battery 1 continues to be supplied as the operation power supply for the control unit 4 even after the inverter 7 is stopped, the assembled battery 1 continues to be discharged even after the assembled battery 1 has dropped below the discharge end voltage. There arises a problem that the deterioration of the assembled battery 1 proceeds.

  Problems such as these are not limited to nickel-metal hydride storage battery systems, but also occur in battery systems that combine secondary batteries such as lithium ion batteries, and battery systems that combine multiple batteries, including primary batteries. It is.

  The present invention has been made in view of such a problem, and the problem to be solved by the present invention is to have one or more assembled batteries in which a plurality of batteries are connected in series and / or in parallel. A battery system, a battery system control method, and a battery system control program capable of supplying power to a load while suppressing overdischarge and deterioration of the battery with respect to a battery system configured to supply power to a load connected in parallel And providing a program recording medium.

  In addition, for example, an inverter from an assembled battery is charged like a backup power supply system that charges an assembled battery storage battery while supplying commercial AC power to the load, and supplies power from the assembled battery to the load in the event of a commercial AC power outage. An object of the present invention is to provide a battery system, a battery system control method, a battery system control program, and a program recording medium for supplying power to a load while suppressing overdischarge and deterioration of the battery.

  The present invention comprises the following technical means in order to solve the above-mentioned problems.

The first technical means is a battery system that has one or more battery packs formed by connecting a plurality of batteries in series and / or in parallel, and supplies power output from the battery pack to a load. The above assembled batteries are connected in parallel and connected to the load, and each of the assembled batteries has a circuit breaker on the output side to the load, and the output voltage of any one of the assembled batteries is The battery pack has means for opening the circuit breaker connected to the output side of the battery pack when the battery pack voltage is less than or equal to a predetermined voltage threshold value, and the remaining one of the circuit breakers is closed. if it becomes, when the output voltage of the remaining one of the battery pack in a state where the circuit breaker is closed is equal to or less than a predetermined voltage threshold, issues an instruction for stopping the operation of the load Later, further Characterized in that it comprises a means for opening the connected circuit breaker on the output side of said set battery after a predetermined elapsed time.

The second technical means is a battery system that has one or more battery packs formed by connecting a plurality of batteries in series and / or in parallel, and supplies power output from the battery pack to a load. The battery packs connected in parallel and connected to the load, each battery pack having a circuit breaker on the output side to the load, as a control unit for controlling the operation of the battery system, Voltage monitoring means for monitoring the output voltage of each assembled battery, circuit breaker control means for transmitting a control signal for controlling opening and closing of the circuit breaker, load control means for transmitting a control signal for controlling the operation of the load, and a time counting means for counting the elapsed time predetermined, and the operating power of the control unit is configured to supply from each of the battery pack through the breaker, the system When the voltage monitoring unit detects that the output voltage of any one of the assembled batteries is equal to or lower than a predetermined voltage threshold value for each of the assembled batteries, the breaker control unit A control signal for opening the circuit breaker connected to the output side of the battery is transmitted to open the circuit breaker, or the voltage monitoring means of the control unit remains in the closed circuit breaker. When it becomes one, when it is detected that the output voltage of the remaining one of the assembled batteries in the closed state of the circuit breaker is less than or equal to a predetermined voltage threshold, the load control means , After transmitting a control signal for stopping the operation of the load, and further counting the passage of a predetermined elapsed time by the time counting means, and then by the breaker control means, Sends a control signal to open the connection to said circuit breaker on the output side, characterized in that for opening the circuit breaker.

A third technical means is the battery system according to the first or second technical manual stage, an alternating current load which the load is driven by AC power, connected to the output side of the one or more sets of the battery pack When the inverter that converts DC power into AC power is connected to a connection point where the circuit breakers connected in parallel are connected, and the load is driven by the output of the inverter, the circuit breaker that is closed Instead of issuing an instruction to stop the operation of the load when the output voltage of the remaining one assembled battery in the state where the circuit breaker is in a closed state becomes equal to or lower than a predetermined voltage threshold value. In addition, an instruction to stop the operation of the inverter is given.

According to a fourth technical means, in the battery system according to any one of the first to third technical means, the battery is a secondary battery.

A fifth technical means is a battery system control method for supplying one or more battery packs formed by connecting a plurality of batteries in series and / or in parallel, and supplying power output from the battery pack to a load, In the battery system control method, one or more sets of the assembled batteries are connected in parallel and connected to the load, and each of the assembled batteries has a circuit breaker on the output side to the load. Has a procedure for opening the circuit breaker connected to the output side of the assembled battery when the voltage is equal to or lower than a predetermined voltage threshold value for each of the assembled batteries, and the closed circuit breaker is closed If the vessel has become remaining one, when the output voltage of the remaining one of the battery pack in a state where the circuit breaker is closed is equal to or less than a predetermined voltage threshold, stops the operation of the load Instructions After further characterized by having a procedure for opening the circuit breaker, which is connected to the output side of said set battery after the elapse of the elapsed time determined in advance.

A sixth technical means is the battery system control method according to the fifth technical means, wherein the load is an AC load driven by AC power, and is connected to an output side of one or more sets of the assembled batteries. In the case where an inverter that converts DC power into AC power is connected to a connection point where the circuit breakers are connected in parallel, and the load is driven by the output of the inverter, the closed circuit breaker remains 1 When the output voltage of the remaining one assembled battery in the closed state of the circuit breaker is equal to or lower than a predetermined voltage threshold, instead of instructing to stop the operation of the load, An instruction to stop the operation of the inverter is given.

A seventh technical means is the cell system control method according to the fifth or sixth technical manual stage, wherein the battery is a secondary battery.

According to an eighth technical means, a battery system control program executing the procedure of the battery system control method according to any of the fifth to seventh technical means as a program executable by a computer. Features.

A ninth technical means is a program recording medium in which the battery system control program according to the eighth technical means is recorded on a computer-readable recording medium.

  According to the battery system, the battery system control method, the battery system control program, and the program recording medium of the present invention, the following effects can be obtained.

  By configuring the battery system, the battery system control method, the battery system control program, and the program recording medium as described in each of the above technical means, the discharge operation of the battery constituting the assembled battery, for example, the secondary battery is overdischarge. Therefore, the battery, for example, the secondary battery can be prevented from deteriorating and the battery life can be extended.

  In addition, when stopping the power supply to the load side of the assembled battery by opening the switch unit such as a circuit breaker inserted in the power wiring, the assembled battery is disconnected from the load side by opening the switch unit. In order to stop the operation of the load being fed from, it is possible to prevent the switch part from being damaged by an arc or the like generated when the switch part is opened, thus extending the life of the circuit breaker or the like. Become.

  Hereinafter, an example of the best embodiment of a battery system, a battery system control method, a battery system control program, and a program recording medium according to the present invention will be described in detail with reference to the drawings.

(Outline of the present invention)
Prior to the description of the embodiments of the present invention, first, the outline of the features of the present invention will be described. The present invention relates to a battery system that has one or more assembled batteries formed by connecting a plurality of batteries in series and / or in parallel, and each assembled battery is connected in parallel to supply power to a load. When the output voltage of the battery falls below a predetermined voltage threshold for each assembled battery, the assembled battery is controlled to be disconnected from the load by opening the circuit breaker provided on the output side. Features. Furthermore, when the remaining battery pack is connected to the load and the output voltage of the remaining battery pack falls below a predetermined voltage threshold, an instruction to stop the load operation is first given. Then, after a predetermined elapsed time has elapsed as a time until the load operation completely stops, control is performed to open the breaker of the assembled battery.

  That is, in the battery system, the battery system control method, the battery system control program, and the program recording medium according to the present invention, the discharge from one or more assembled batteries formed by connecting a plurality of batteries in series and / or in parallel to the load. When a decrease in the output voltage of any one of the assembled batteries is detected, the circuit breaker provided on the output side of the assembled battery is opened and the circuit breaker is closed When a drop in the output voltage of the remaining one assembled battery that has been in a closed state is detected when the number of remaining ones becomes one, the load is stopped before the circuit breaker is opened. Later, the circuit breaker is opened.

  Further, the power supply to the control unit that controls the opening / closing operation of the circuit breaker connected to each of the one or more battery packs is performed via the circuit breaker, thereby providing one or more circuit breakers. In a state where all of the battery packs are opened, the power supply to the control unit is also stopped, and the discharging operation of the assembled battery can be completely stopped.

  As a result, it is possible to prevent deterioration due to overdischarge of the assembled battery and to prevent damage to the circuit breaker due to an arc or the like that may occur when the assembled battery is disconnected from the load.

  Hereinafter, the embodiment of the present invention will be described by taking as an example the case where the battery constituting the assembled battery is a secondary battery of a nickel hydride storage battery, but the present invention is not limited to the case of a nickel hydride storage battery. Absent. For example, a battery system composed of a combination of secondary batteries other than nickel metal hydride storage batteries, such as a plurality of lithium ion batteries and lead storage batteries, or a battery system composed of a combination of a plurality of batteries including a primary battery. Can be applied in exactly the same way.

  In addition, although it demonstrates taking the case where a nickel hydride storage battery is connected in series and comprises an assembled battery, even if it connects a nickel hydride storage battery in series and / or in parallel and comprises an assembled battery, it applies exactly the same. Can do.

  In addition, when the load is an AC load driven by AC power, the present invention can also be applied to a battery system that converts DC power from an assembled battery into AC power via an inverter and supplies power to the load. it can.

<Example 1>
(When battery pack is one battery system)
FIG. 1 is a configuration diagram illustrating an embodiment of the battery system of the present invention, and shows a case where the assembled battery is composed of one set. In FIG. 1, a nickel-metal hydride storage battery (for example, a single cell rated voltage of 1.2 V, a rated capacity of 95 Ah, and a minimum operating voltage of 1.0 V) is connected in series with 10 cells, whereby an assembled battery 1 (rated voltage of 12 V and rated capacity of 95 Ah) Is connected to the load 2. The electric power output from the assembled battery 1 is supplied to the load 2, and the breaker 3 is provided on the output side of the assembled battery 1, and the assembled battery 1 is connected to the load 2 through the breaker 3. The load 2 can be operated and stopped by an external control signal. In the present embodiment, a case where 10 nickel hydride storage battery cells are connected in series will be described. However, the assembled battery 1 may be configured by connecting a plurality of batteries having an arbitrary number of cells in series and / or in parallel. I do not care.

  In the configuration of FIG. 1, the minimum use voltage (discharge end voltage) of the assembled battery 1 is 10 V (= minimum use voltage 1.0 V × 10 cells per cell), and when discharging continues below this minimum use voltage. Deterioration due to overdischarge can occur.

  The control unit 4 can monitor the output voltage of the assembled battery 1, transmit a control signal for controlling the operation and stop of the load 2, and transmit a control signal for opening and closing the circuit breaker 3. That is, as shown in FIG. 1, the control unit 4 is a voltage monitoring unit 4 a that is a voltage monitoring unit that monitors the output voltage of the assembled battery 1, and a circuit breaker control unit that transmits a control signal for controlling the opening and closing of the circuit breaker 3. Circuit breaker control unit 4b, load control unit 4c as load control means for transmitting a control signal for controlling the operation of load 2, and time counting unit 4d for counting a predetermined elapsed time. ing. Note that the operation power of the control unit 4 is supplied from the assembled battery 1 via the circuit breaker 3 as shown in FIG.

  FIG. 2 is a flowchart for explaining the flow of control of the load 2 and the circuit breaker 3 by the control unit 4 in the battery system shown in FIG. 1, and shows an example of the battery system control method of the present invention. The battery system control method may be implemented as a battery system control program that can be executed by a computer, or the battery system control program may be recorded on a computer-readable program recording medium.

  In FIG. 2, when the battery system is started and the control operation as the battery system is started, the control unit 4 first generates a control signal for operating the load 2 by the load control unit 4c, and transmits the control signal to the load 2. 2 is operated (step S21). Thereafter, the control unit 4 monitors the output voltage Vd of the assembled battery 1 by the voltage monitoring unit 4a, and the output voltage Vd is a voltage threshold V1 determined in advance for the assembled battery 1 (that is, the minimum operating voltage 10V of the assembled battery 1). Is exceeded (NO in step S22), the monitoring operation of the output voltage Vd of the assembled battery 1 in step S22 is repeated.

  On the other hand, when the output voltage Vd of the assembled battery 1 becomes equal to or lower than the voltage threshold value V1 (that is, 10 V) (YES in step S22), the process proceeds to step S23, and the control unit 4 first operates the load 2 by the load control unit 4c. After generating a control signal for stopping the operation and giving an instruction to stop the operation of the load 2 (step S23), a predetermined elapsed time T2 (for example, 1 second) has elapsed as a time until the load 2 stops. When this is detected by the time counting unit 4d, the circuit breaker control unit 4b generates a control signal for opening the circuit breaker 3 and opens the circuit breaker 3 (step S24).

  Here, as described above, by setting the minimum usable voltage (discharge end voltage) of the assembled battery 1 as the voltage threshold value V1, battery deterioration due to overdischarge can be prevented. Further, as the elapsed time T2, by setting the time until the power consumption of the load 2 is minimized after the operation of the load 2 is completely stopped, when the circuit breaker 3 is opened, in the switch section of the circuit breaker 3 Generation | occurrence | production of an arc etc. can be suppressed and damage to the switch part of the circuit breaker 3 can be prevented.

  By executing the control as described above, while the output voltage Vd of the assembled battery 1 is larger than the minimum operating voltage 10V, power is supplied from the assembled battery 1 to the load 2 and the operation of the load 2 is continued. When Vd becomes the minimum operating voltage of 10 V or less, the load 2 is stopped and the circuit breaker 3 is opened after the power consumption of the load 2 is reduced.

  However, depending on the configuration of the circuit breaker 3 and the power capacity of the battery system, even when the output voltage of the assembled battery 1 becomes a minimum operating voltage of 10 V or less, the circuit breaker can be operated without stopping the operation of the load 2. 3 may be configured to open.

  In the case of application to a power supply system for an AC load having a configuration as shown in FIG. 5, the load 2 can be read as an inverter 7 in FIG. That is, the load is an AC load 9 driven by AC power, and an inverter 7 that converts DC power to AC power is connected to the circuit breaker 3 connected to the output side of the assembled battery 1. When the AC load 9 is configured to be driven, when the output voltage of the assembled battery 1 is equal to or lower than a predetermined voltage threshold, that is, the minimum operating voltage is 10 V or lower, instead of giving an instruction to stop the operation of the AC load 9, An instruction to stop the operation of the inverter 7 may be issued.

  In general, the inverter 7 has a function of operating and stopping by an external signal. Therefore, when the inverter 7 receives the operation stop signal from the control unit 4, the output of the inverter 7 can be stopped. After the output of the inverter 7 stops and the discharge from the assembled battery 1 to the inverter 7 stops completely, the power consumption of the assembled battery 1 becomes only the control unit 4 and then shuts off. By instructing the opening of the device 3, the circuit breaker 3 is safely opened and the discharge of the assembled battery 1 is completely stopped.

<Example 2>
(In case of 3 battery sets)
FIG. 3 is a configuration diagram illustrating an embodiment different from the first embodiment of the battery system of the present invention, and shows a case where the assembled battery is composed of three sets. However, even when the battery is composed of an arbitrary plurality of assembled batteries, it is exactly the same as the present embodiment. In FIG. 3, nickel hydride storage batteries (for example, a single cell rated voltage of 1.2 V, a rated capacity of 95 Ah, and a minimum operating voltage of 1.0 V) are connected in series by 10 cells, whereby three sets of assembled batteries 1 (1a, 1b, 1c) (respectively rated voltage 12V, rated capacity 95Ah), three sets of assembled batteries 1 (1a, 1b, 1c) are connected in parallel on the respective output sides, and connected from the parallel connection point to the load 2.

  The electric power output from the three sets of assembled batteries 1 (1a, 1b, 1c) is supplied to the load 2, but the breaker 3 (3a, 3a, 1c) is connected to the output side of each assembled battery 1 (1a, 1b, 1c). 3b, 3c), and the assembled battery 1 (1a, 1b, 1c) is connected to the parallel connection point via the circuit breaker 3 (3a, 3b, 3c), and the load 2 via the parallel connection point. Connected to. The load 2 can be operated and stopped by an external control signal. Further, in this embodiment, a case where 10 nickel-metal hydride storage battery cells are connected in series will be described. As each assembled battery 1 (1a, 1b, 1c), a plurality of batteries having an arbitrary number of cells are connected in series and / or You may comprise by connecting in parallel.

  In the configuration of FIG. 3, the minimum operating voltage (end-of-discharge voltage) of each of the three batteries 1 (1a, 1b, 1c) is 10V (= minimum operating voltage 1.0V × 10 cells per cell). If the discharge is continued below this minimum operating voltage, deterioration due to overdischarge can occur.

  The control unit 4 monitors the output voltage of each assembled battery 1 (1a, 1b, 1c), transmits a control signal for controlling the operation and stop of the load 2, and opens and closes the circuit breaker 3 (3a, 3b, 3c). A control signal can be transmitted. That is, as shown in FIG. 3, the control unit 4 transmits a control signal that controls the opening and closing of the circuit breaker 3, the voltage monitoring unit 4 a that is a voltage monitoring unit that monitors the output voltage of each assembled battery 1. It comprises at least a circuit breaker control unit 4b that is a means, a load control unit 4c that is a load control unit that transmits a control signal for controlling the operation of the load 2, and a time counting unit 4d that counts a predetermined elapsed time. Has been. In addition, as shown in FIG. 3, the operation power supply of the control part 4 is supplied from each assembled battery 1 (1a, 1b, 1c) via the circuit breaker 3 (3a, 3b, 3c).

  FIG. 4 is a flowchart for explaining the flow of control of the load 2 and the circuit breaker 3 by the control unit 4 in the battery system shown in FIG. 3, and shows an example different from the embodiment 1 of the battery system control method of the present invention. Yes. The battery system control method may be implemented as a battery system control program that can be executed by a computer, or the battery system control program may be recorded on a computer-readable program recording medium.

  In FIG. 4, when the battery system is started and the control operation as the battery system is started, the control unit 4 first generates a control signal for operating the load 2 by the load control unit 4c, and transmits the control signal to the load 2. 2 is operated (step S41). Thereafter, the control unit 4 is in a state in which the circuit breaker 3 (3a, 3b, 3c) is closed among the assembled batteries 1 (1a, 1b, 1c) (YES in steps S42, S47, S52). In the case of the assembled battery 1, the output voltage Va, Vb, Vc of each corresponding assembled battery 1 (1 a, 1 b, 1 c) is equal to or lower than a predetermined voltage threshold V 1 (that is, the lowest usable voltage of each assembled battery 1). Is monitored by the voltage monitoring unit 4a (steps S43, S48, S53).

  While the output voltage Va, Vb, Vc of each assembled battery 1 (1a, 1b, 1c) exceeds a predetermined voltage threshold V1 for each assembled battery 1 (1a, 1b, 1c) (steps S43, S48) , S53, NO), the closed state of each circuit breaker 3 (3a, 3b, 3c) and the monitoring operation of the voltage level of the output voltage Va, Vb, Vc of each assembled battery 1 (1a, 1b, 1c) are repeated, There is no change in the operation of the load 2 and the open / close state of the circuit breaker 3 (3a, 3b, 3c).

  Here, when the output voltage of any one of the assembled batteries 1 (1a, 1b, 1c) becomes equal to or lower than the voltage threshold value V1 (10 V), any of steps S43, S48, and S53 is YES. ), The control unit 4 generates a control signal for opening the circuit breaker 3 of the corresponding assembled battery 1 by the circuit breaker control unit 4b, and opens the circuit breaker 3 (step S46, S51, S56). ).

  However, when only one circuit breaker 3 is closed (YES in any one of steps S44, S49, S54), the corresponding assembled battery 1 (1a, 1b, 1c) When the output voltages Va, Vb, and Vc of the output voltage become equal to or lower than the voltage threshold value V1 (10V), the control unit 4 first generates a control signal for stopping the operation of the load 2 by the load control unit 4c. After giving an instruction to stop the operation (any one of steps S45, S50, and S55), it is a time that a predetermined elapsed time T2 (for example, 1 second) has elapsed as a time until the load 2 stops. When detected by the counting unit 4d, the circuit breaker control unit 4b generates a control signal for opening the corresponding circuit breaker 3 and opens the circuit breaker 3 (any one of steps S46, S51, S56). Step).

  Here, as described above, by setting the minimum usable voltage (discharge end voltage) of each assembled battery 1 (1a, 1b, 1c) as the voltage threshold value V1, battery deterioration due to overdischarge is prevented. be able to. Further, as the elapsed time T2, by setting the time until the power consumption of the load 2 is minimized after the operation of the load 2 is completely stopped, when the circuit breaker 3 (3a, 3b, 3c) is opened, Generation | occurrence | production of the arc etc. in the switch part of the circuit breaker 3 can be suppressed, and damage to the switch part of the circuit breaker 3 can be prevented.

  By executing the control as described above, each assembled battery 1 (1a, 1b, 1c) is output while the output voltage Va, Vb, Vc of each assembled battery 1 (1a, 1b, 1c) is higher than the minimum operating voltage 10V. ) Is supplied to the load 2 and the operation of the load 2 continues. On the other hand, when one of the output voltages Va, Vb, and Vc becomes a minimum operating voltage of 10 V or less, the corresponding assembled battery 1 (1a, 1b, 1c) ) Circuit breaker 3 (3a, 3b, 3c) is opened, and when the output voltage of the last set of assembled battery 1 falls below the minimum operating voltage of 10 V, load 2 is stopped first. The corresponding circuit breaker 3 is opened after the power consumption of the load 2 is reduced.

  The output voltage of the assembled battery 1 (1a, 1b, 1c) when the circuit breaker 3 (3a, 3b, 3c) is opened is the same as that of the assembled battery 1 (1a, 1b, 1c) in Example 2. Are set to the same voltage threshold value V1 (that is, the minimum operating voltage of the assembled battery 1 (1a, 1b, 1c) is 10V) or less, but it is not always necessary to set the same value in each assembled battery 1 (1a, 1b, 1c). Absent. When there is a difference in the deterioration state between the assembled batteries 1 (1a, 1b, 1c), it is also possible to set different voltage thresholds, that is, discharge end voltages for the assembled batteries 1 (1a, 1b, 1c). It is.

  Also, depending on the configuration of the circuit breaker 3 (3a, 3b, 3c) and the power capacity of the battery system, the output voltage of the last remaining one set of the assembled battery 1 is less than the minimum operating voltage of 10V. However, the circuit breaker 3 may be opened without stopping the operation of the load 2.

  In the case of application to a power supply system for an AC load having a configuration as shown in FIG. 5, by replacing the load 2 with the inverter 7 in FIG. That is, the load is an AC load 9 driven by AC power, and the circuit breakers 3 (3a, 3b, 3c) respectively connected to the output sides of one or more battery packs 1 (1a, 1b, 1c) are connected in parallel. When the inverter 7 that converts DC power to AC power is connected to the connected connection point, and the AC load 9 is driven by the output of the inverter 7, the remaining circuit breaker 3 is the remaining one. An instruction to stop the operation of the AC load 9 when the output voltage of the remaining one assembled battery 1 in a state where the circuit breaker 3 is closed is equal to or lower than a predetermined voltage threshold, that is, a minimum operating voltage of 10 V or lower. Instead of performing, an instruction to stop the operation of the inverter 7 may be performed.

  In general, the inverter 7 has a function of operating and stopping by an external signal. Therefore, when the inverter 7 receives the operation stop signal from the control unit 4, the output of the inverter 7 can be stopped. After the output of the inverter 7 stops and the discharge from the remaining set of assembled batteries 1 to the inverter 7 stops completely, the power consumption of the remaining set of assembled batteries 1 is only the control unit 4. After reaching the state, by instructing the opening of the closed circuit breaker 3, the circuit breaker 3 is safely opened and the discharge of the assembled battery 1 is completely stopped.

(Effect obtained by the present invention)
As described above in detail, the battery system according to the present invention is characterized in that in a battery system that supplies power output from an assembled battery formed by combining a plurality of batteries to a load, a circuit breaker is provided on the output side of the assembled battery. And when the output voltage of the assembled battery falls below a predetermined voltage threshold during discharging, control is performed to open the circuit breaker provided on the output side of the assembled battery, and the remaining 1 In the case of opening a pair of circuit breakers, it is also possible to control to stop the operation of the load before opening the circuit breakers.

  By having such characteristics, the energy stored in the battery is effectively supplied to the load while preventing the battery from being deteriorated due to overdischarge, and the operation of the load is stopped before the end of the discharge. It is possible to provide a power supply system that prevents damage to the device.

  As described above, the embodiment of the present invention has been described by taking the case where the battery is a nickel-metal hydride storage battery as an example. However, as described above, the present invention is not limited to such a case. For example, a plurality of lithium ions Whether it is a battery system consisting of a combination of secondary batteries other than nickel-metal hydride storage batteries, such as batteries and lead storage batteries, or a battery system consisting of a combination of multiple batteries including primary batteries, the same applies. can do.

  Next, the effect obtained by the present invention will be described.

  (1) In a battery system that supplies energy output from a battery such as a secondary battery to a load, if the battery continues to discharge below the end-of-discharge voltage and enters an overdischarge state, the battery such as a secondary battery deteriorates. This causes a problem that the storage capacity decreases.

  According to the present invention, since a battery such as a secondary battery whose output voltage has dropped below the discharge end voltage immediately stops discharging, it is possible to configure a battery system that suppresses overdischarge and deterioration of the battery such as a secondary battery. Become.

  (2) In a battery system that supplies power output from a battery to a load, when the power supply is stopped by opening the switch part such as a circuit breaker inserted in the power wiring, the switch part may be damaged by an arc at the time of opening. There arises a problem that the life of the receiving circuit breaker and the like is reduced.

  According to the present invention, the operation of the load is stopped before opening the switch unit such as a circuit breaker, and the switch unit is opened after the minimum power consumption is reached. It becomes possible to prevent, and the lifetime of a circuit breaker etc. can be extended.

It is a block diagram illustrating an embodiment of the battery system of the present invention. 2 is a flowchart illustrating a flow of control of a load and a circuit breaker by a control unit in the battery system shown in FIG. 1. It is a block diagram illustrating an embodiment different from the first embodiment of the battery system of the present invention, 4 is a flowchart illustrating a flow of control of a load and a circuit breaker by a control unit in the battery system shown in FIG. 3. It is a block diagram of the power supply system which supplies commercial power to a load, charging a storage battery, and supplies the electric power which a storage battery outputs to a load at the time of a power failure.

Explanation of symbols

1, 1a, 1b, 1c ... assembled battery, 2 ... load, 3, 3a, 3b, 3c ... circuit breaker, 4 ... control unit, 4a ... voltage monitoring unit, 4b ... circuit breaker control unit, 4c ... load control unit, 4d ... time counting unit, 5 ... AC input, 6 ... charger, 7 ... inverter, 8 ... switch, 9 ... AC load, 10 ... bypass circuit.

Claims (9)

A battery system having one or more battery packs formed by connecting a plurality of batteries in series and / or in parallel, and supplying power output from the battery pack to a load, wherein one or more battery packs are connected in parallel Connected to the load, and each of the assembled batteries has a circuit breaker on the output side to the load, the output voltage of any of the assembled batteries is predetermined for each of the assembled batteries. and when it becomes below the voltage threshold, comprising means for opening the circuit breaker, which is connected to the output side of said set battery, and, when the circuit breaker is closed becomes remaining one, said After the instruction to stop the operation of the load when the output voltage of the remaining one assembled battery in a state where the circuit breaker is closed is equal to or lower than a predetermined voltage threshold, the predetermined voltage is further determined. Cell system, characterized in that it comprises a means for opening the circuit breaker, which is connected to the output side of said set battery after elapse of the over-time.   A battery system having one or more battery packs formed by connecting a plurality of batteries in series and / or in parallel, and supplying power output from the battery pack to a load, wherein one or more battery packs are connected in parallel In the battery system having a circuit breaker on the output side to the load, each of the assembled batteries is connected to the load, and the output voltage of each of the assembled batteries is used as a control unit that controls the operation of the battery system. Voltage monitoring means for monitoring, circuit breaker control means for transmitting a control signal for controlling opening / closing of the circuit breaker, load control means for transmitting a control signal for controlling the operation of the load, and counting a predetermined elapsed time Time counting means, and is configured to supply the operating power of the control unit from each of the assembled batteries via the circuit breaker, and the voltage monitoring of the control unit When the stage detects that the output voltage of any one of the assembled batteries is equal to or lower than a predetermined voltage threshold value for each of the assembled batteries, the circuit breaker control means causes the output voltage of the assembled battery to A control signal for opening the connected circuit breaker is transmitted to open the circuit breaker, or the voltage monitoring means of the control unit is left as one of the closed circuit breakers. In this case, when it is detected that the output voltage of the remaining one assembled battery in the closed state of the circuit breaker is equal to or lower than a predetermined voltage threshold value, the load control means controls the operation of the load. Is transmitted to the output side of the assembled battery by the circuit breaker control means after counting the passage of a predetermined elapsed time by the time counting means. Cell system which transmits a control signal to open, characterized in that for opening the circuit breaker the circuit breaker was. 3. The battery system according to claim 1, wherein the load is an AC load driven by AC power, and the connection point where the circuit breakers connected to the output side of one or more sets of the battery packs are connected in parallel. When the inverter for converting DC power to AC power is connected and the load is driven by the output of the inverter, the closed circuit breaker is the remaining one, and the circuit breaker is closed. When the output voltage of the remaining one of the assembled batteries in the set state falls below a predetermined voltage threshold value, an instruction to stop the operation of the inverter is issued instead of an instruction to stop the operation of the load. A battery system characterized by that. The battery system according to any one of claims 1 to 3, a battery system, wherein the battery is a secondary battery. A battery system control method that includes one or more battery packs formed by connecting a plurality of batteries in series and / or in parallel, and that supplies power output from the battery pack to a load, wherein the battery pack includes one or more battery packs. Are connected in parallel and connected to the load, and each of the assembled batteries has a circuit breaker on the output side to the load, the output voltage of any one of the assembled batteries is the respective assembled battery. When the voltage threshold is less than or equal to a predetermined voltage threshold value, a procedure for opening the circuit breaker connected to the output side of the assembled battery is provided, and the remaining circuit breaker is one remaining. If the, when the output voltage of the remaining one of the battery pack in a state where the circuit breaker is closed is equal to or less than a predetermined voltage threshold, after the command to stop the operation of the load, further Cell system control method characterized by having a procedure to open a connection to said circuit breaker after a predetermined elapsed time to the output side of said set battery. 6. The battery system control method according to claim 5 , wherein the load is an AC load driven by AC power, and is connected to a connection point in which the breakers connected to the output side of one or more sets of the assembled batteries are connected in parallel. When the inverter for converting DC power to AC power is connected and the load is driven by the output of the inverter, the closed circuit breaker is the remaining one, and the circuit breaker is closed. When the output voltage of the remaining one of the assembled batteries in the set state falls below a predetermined voltage threshold value, an instruction to stop the operation of the inverter is issued instead of an instruction to stop the operation of the load. A battery system control method. 7. The battery system control method according to claim 5 , wherein the battery is a secondary battery. The procedure of the battery system control method according to any one of claims 5 to 7, the battery system control program, characterized by being implemented as a program executable by a computer. 9. A program recording medium, wherein the battery system control program according to claim 8 is recorded on a computer-readable recording medium.

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