JP6749166B2 - Large capacity battery system - Google Patents

Description

The present invention relates to a large capacity storage battery system.

BACKGROUND ART Conventionally, there is known a technique related to a storage battery system in which a plurality of storage batteries are connected in parallel to a load and power is supplied to the load without interruption. For example, Patent Document 1 discloses a discharge device including a plurality of storage batteries connected in parallel to a load and a plurality of switching elements that are respectively connected in series to the plurality of storage batteries and turn on/off a discharge current path of each storage battery. Has been done. In this discharge device, one switching element is turned on and only the corresponding storage battery is discharged, and when this storage battery becomes below the discharge completion voltage, the corresponding switching element is turned off and the other switching element is turned on. Then, electric power is supplied to the load from each of the plurality of storage batteries.

JP, 10-123225, A

When the single cell capacity of the storage battery is small, it is preferable to connect multiple storage batteries in parallel with the power supply target in order to store sufficient power, but connect multiple storage batteries in parallel with the power supply target. If it is continued, a large short circuit current will flow from the plurality of storage batteries to the power supply target side when a short circuit occurs in the circuit. Therefore, if the switching element corresponding to the storage battery that is not used is turned off as in the discharge device disclosed in Patent Document 1, it is possible to prevent a large current from flowing when a short circuit occurs. However, in the discharge device of Patent Document 1, the switching element corresponding to the storage battery being used is turned off and the switching element corresponding to the storage battery to be used next is turned on at the same time, so control at the time of switching the storage battery is performed. It becomes complicated. Further, the discharge device of Patent Document 1 requires the same number of switching elements as the number of storage batteries in parallel.

The present invention has been made in view of the above, and in a large-capacity storage battery system in which a plurality of storage batteries are connected in parallel to the power supply target, while ensuring safety, the power supply target does not need to be provided with a simpler configuration and control. The purpose is to supply power to a power outage.

In order to solve the above-mentioned problems and achieve the object, the present invention includes a first storage battery group including at least one first storage battery module having a plurality of storage batteries, and a plurality of storage batteries connected to the power supply target. A second storage battery group including at least one second storage battery module having the second storage battery group connected in parallel to the first storage battery group to the power supply target, and from the first storage battery group to the power supply target when a trigger signal is input. When a reverse bias voltage is applied in the conductive state in which the power is supplied and in the conductive state and the trigger signal is not input, the power supply from the first storage battery group to the power supply target is cut off. A first thyristor switch that is in a non-conducting state and a conducting state in which electric power is supplied from the second storage battery group to the power supply target when a trigger signal is input, and the conducting state and the trigger signal are input. A second thyristor switch in a non-conducting state that cuts off the supply of electric power from the second storage battery group to the power supply target when a reverse bias voltage is applied in a non-conducting state, the first thyristor switch and the second thyristor A control unit for outputting the trigger signal to a switch, wherein the control unit outputs the trigger signal to the first thyristor switch to bring the first thyristor switch into the conducting state, and to the first storage battery group. Electric power is supplied from the included first storage battery module to the power supply target, and the trigger signal to the first thyristor switch is supplied before the voltage of the first storage battery module during power supply becomes equal to or lower than the switching voltage. The output is stopped and the trigger signal is output to the second thyristor switch to output the trigger signal to the second thyristor switch when the voltage of the first storage battery module during power supply becomes equal to or lower than the switching voltage. It is characterized in that the second storage battery module before power supply included in the second storage battery group supplies power to the power supply target in a conductive state.

In the large-capacity storage battery system of the present invention, when the voltage of the first storage battery module during power supply is not lower than the switching voltage, the other first storage battery module and the second storage battery group may be separated from the power supply target. it can. As a result, when a short circuit occurs in the circuit, it is possible to prevent an excessive current from flowing from the first storage battery group and the second storage battery group connected in parallel to the power supply target to the power supply target. On the other hand, when the voltage of the first storage battery module during power supply becomes equal to or lower than the voltage at the time of switching, the second thyristor switch is turned on, and the power is supplied from the second storage battery module included in the second storage battery group before power supply. The supply of electric power is started. As a result, the first thyristor switch corresponding to the first storage battery module whose voltage has dropped to the voltage equal to or lower than the switching voltage is automatically brought into a non-conducting state by applying the reverse bias voltage. That is, it is possible to switch the storage battery group that supplies power to the power supply target by simply outputting the trigger signal to one thyristor switch. Further, even when the first storage battery module and the second storage battery module have a plurality of storage batteries connected in parallel, a switching element corresponding to each storage battery module and a thyristor switch corresponding to each storage battery group may be used. It is not necessary to provide switching elements according to the number of storage batteries in parallel. Therefore, according to the large-capacity storage battery system of the present invention, in a large-capacity storage battery system in which a plurality of storage batteries are connected in parallel to the power supply target, while ensuring safety, the power supply target can be uninterrupted with a simpler configuration and control. Power can be supplied.

Further, the first storage battery group includes a plurality of the first storage battery modules connected in parallel to the power supply target, and the second storage battery group includes a plurality of the second storage battery modules connected in parallel to the power supply target. A plurality of first switching elements, each of which has a storage battery module and is on/off controlled by the control unit to switch between connection and disconnection of each of the first storage battery modules and the first thyristor switch; and on/off by the control unit. A plurality of second switching elements that are controlled and switch between connection and disconnection of each of the second storage battery modules and the second thyristor switch are further included, and the control unit includes one of the first switching elements. One of the first storage battery modules included in the first storage battery group to the power supply target by turning on one of them and outputting a trigger signal to the first thyristor switch to bring the first thyristor switch into the conductive state. Power is supplied, and the output of the trigger signal to the first thyristor switch is stopped before the voltage of the first storage battery module during the power supply becomes equal to or lower than the switching voltage, and the power is being supplied. When the voltage of the first storage battery module becomes equal to or lower than a predetermined voltage higher than the switching voltage, the second switching element corresponding to one of the second storage battery modules before the power supply is turned on. Every time, when the voltage of the first storage battery module during the power supply becomes equal to or lower than the switching voltage, the trigger signal is output to the second thyristor switch to make the second thyristor switch conductive, and It is preferable that power be supplied from one of the second storage battery modules before power supply to the power supply target.

Accordingly, when the voltage of the first storage battery module that is supplying power is not lower than the switching voltage, the storage battery modules other than the first storage battery module are disconnected from the power supply target by turning off the corresponding switching element. be able to. As a result, while further improving the capacities of the first storage battery group and the second storage battery group, when a short circuit occurs in the circuit, an excessive current is supplied from the storage battery modules connected in parallel to the power supply target to the power supply target. It is possible to suppress the flow and ensure safety. Further, when the voltage of the first storage battery module during power supply becomes equal to or lower than a predetermined voltage higher than the switching voltage, the second switching element corresponding to one of the second storage battery modules before power supply is turned on. By so setting, when the voltage of the first storage battery module during power supply becomes equal to or lower than the voltage at the time of switching, a trigger signal is output to the second thyristor switch to quickly supply power from the second storage battery module before power supply. Power can be supplied to the target. In other words, it is possible to switch the storage battery module that supplies power to the power supply target by simply outputting the trigger signal to one thyristor switch. As a result, the power of the first storage battery group and the second storage battery group can be further improved, and the power can be supplied to the power supply target with uninterrupted power by simpler control.

Further, a charging power supply unit that supplies charging power to the first storage battery group and the second storage battery group, and on/off control by the control unit, and the connection and connection between the first storage battery group and the charging power supply unit. And a second charging-side switching element that is on/off controlled by the control unit and that switches between connection and cancellation of the connection between the second storage battery group and the charging power supply unit. Further comprising, when the charging power is not supplied from the charging power supply unit to the first storage battery group and the second storage battery group, the control unit includes the first charging side switching element and the second charging side switching device. It is preferable to turn off the device.

As a result, the first storage battery group and the second storage battery group can be separated from the charging power supply unit except when the charging power is supplied, so that the safety can be further improved. Further, by avoiding the constant charging of the storage battery, it is possible to favorably suppress the generation of hydrogen gas and the like from the inside of the storage battery, particularly when the storage battery is a lithium ion battery having a flammable electrolyte, It is possible to satisfactorily suppress an abnormality associated with thermal runaway that may be a concern during charging.

Further, a power source power supply unit that supplies power from a power source different from those of the first storage battery group and the second storage battery group to the power supply target, and on/off control by the control unit. A first power feeding side switching element that switches between connection with a target and disconnection, and on/off control by the control unit, one end of which is connected between the first power feeding side switching element and the power feeding target and the other end of which is connected. Is connected between the charging power supply unit and the first charging side switching element and the second charging side switching element, and switches connection and disconnection between the charging power supply unit and the power supply target. And a second power feeding side switching element, wherein the control unit turns on the first power feeding side switching element and supplies power to the power feeding target from the power source power feeding unit. When turning off the element and performing maintenance and inspection of the power supply unit, it is preferable to turn off the first power feeding side switching element and turn on the second power feeding side switching element.

As a result, when the first charging side switching element or the second charging side switching element is turned on in the state where the first power feeding side switching element is turned on and the second power feeding side switching element is turned off, the power source power supply unit The charging power can be supplied from the charging power supply unit to the first storage battery group or the second storage battery group while supplying power to the power supply target. At this time, the first thyristor switch and the second thyristor switch prevent the current from the power source power supply unit from flowing toward the first storage battery group and the second storage battery group, so that the charging power supply unit transfers the first storage battery. It is possible to accurately control the charging power supplied to the group or the second storage battery group to a charging current and a charging voltage that match the charging characteristics of the storage battery. Further, when performing maintenance and inspection of the power supply unit, the first power supply side switching element is turned off and the second power supply side switching element is turned on to supply power from the charging power supply unit to the power supply target. It is possible to supply power to the power supply target while performing maintenance and inspection of the power supply unit.

Further, a circuit breaker provided between the first storage battery group and the second storage battery group and the power supply target is further provided, and a plurality of the storage batteries in the first storage battery module and the second storage battery module are the power supply targets. When connected in parallel with respect to, the number of parallel storage batteries, the number of the short-circuit current is less than the rated breaking capacity of the circuit breaker, when a short-circuit current flows from the first storage battery module or the second storage battery module. Is preferred.

In this way, while the short-circuit current that can flow from each of the first storage battery modules or the second storage battery modules does not exceed the rated breaking capacity of the circuit breaker, a plurality of the storage battery modules are connected in parallel to the power supply target. Then, it becomes possible to sufficiently improve the storage capacity of the entire first storage battery group and the second storage battery group, even though a relatively simple (general) circuit breaker is used.

The storage battery may be any one of a lithium ion battery, a nickel hydrogen battery, an all-solid battery, a metal/air battery, an organic secondary battery, a lithium metal battery, a sodium ion battery, a magnesium ion battery and an aluminum ion battery. preferable.

According to the present invention, even when such a storage battery having a small single cell capacity is used, it is possible to secure a sufficient stored power by connecting a plurality of storage batteries in parallel to a power supply target while ensuring safety. it can.

The large-capacity storage battery system according to the present invention, in a large-capacity storage battery system in which a plurality of storage batteries are connected in parallel to the power supply target, supplies power to the power supply target uninterruptively with a simpler configuration and control while ensuring safety. There is an effect that can be done.

FIG. 1 is a schematic diagram showing a large-capacity storage battery system according to an embodiment. FIG. 2 is a schematic diagram showing a state where the storage battery module included in the first storage battery group and the power supply target are connected in the large capacity storage battery system of FIG. 1. FIG. 3 is a schematic diagram showing a state in which the storage battery module included in the second storage battery group and the power supply target are connected in the large capacity storage battery system of FIG. 1.

Embodiments of a large-capacity storage battery system according to the present invention will be described below in detail with reference to the drawings. The present invention is not limited to this embodiment.

FIG. 1 is a schematic diagram showing a large-capacity storage battery system according to an embodiment. The large-capacity storage battery system 1 shown in FIG. 1 is an apparatus for supplying electric power to a power supply target 50 included in various plant equipment such as nuclear power plant equipment without interruption. The power supply target 50 is a device such as various measuring instruments in a plant facility. In the present embodiment, the power supply target 50 is supplied with direct current power of, for example, 125V.

As shown in FIG. 1, the large-capacity storage battery system 1 cannot supply power from the AC power supply 11 and the first power supply unit (power supply power supply unit) 10 that supplies the power of the AC power supply 11 to the power supply target 50. Second power supply unit 20 for supplying stored power to the power supply target 50, supply of charging power to the second power supply unit 20, and AC power supply to the power supply target 50 during maintenance and inspection of the first power supply unit 10. A third power supply unit (charging power supply unit) 30 that supplies power from 11 and a control unit 40 that controls the first power supply unit 10, the second power supply unit 20, and the third power supply unit 30. Prepare

The first power supply unit 10 includes an AC power supply 11 that is a commercial AC power supply, and a rectifier 12 that is connected to the AC power supply 11 and the power supply target 50. The AC power supply 11 is, for example, a commercial AC power supply. The rectifier 12 converts the AC power from the AC power supply 11 into DC power and supplies the DC power to the power supply target 50. A circuit breaker (MCCB) 60 is provided between the rectifier 12 and the power supply target 50. The circuit breaker 60 interrupts a short circuit current. The rated breaking capacity of the circuit breaker 60 is, for example, 40 kA.

The second power supply unit 20 includes a first storage battery group 21 connected to the power supply target 50, a second storage battery group 22 connected to the power supply target 50 in parallel with the first storage battery group 21, and a first storage battery group 21. A first thyristor switch SCR1 that rectifies a current flow in one direction toward the power supply target 50 side; a second thyristor switch SCR2 that rectifies a current flow in one direction from the second storage battery group 22 toward the power supply target 50 side; The switching element S11 and the switching element S12 as the first switching element provided between the first storage battery group 21 and the first thyristor switch SCR1 and the second storage battery group 22 and the second thyristor switch SCR2. A switching element S21 and a switching element S22 as second switching elements, a voltage sensor 23 that detects the voltage V21 of the first storage battery group 21, and a voltage sensor 24 that detects the voltage V22 of the second storage battery group 22 are provided.

The first storage battery group 21 includes a storage battery module 211 and a storage battery module 212 as a first storage battery module in which a plurality of storage batteries are connected in series and in parallel. The second storage battery group 22 includes a storage battery module 221 and a storage battery module 222 as a second storage battery module in which a plurality of storage batteries are connected in series and in parallel. The number of series of storage batteries included in each storage battery module 211, 212, 221, 222 is set according to the voltage of the power to be supplied to the power supply target 50. Further, the number of parallel storage batteries included in each storage battery module 211, 212, 221, 222 is determined by the short circuit current from each storage battery module 211, 212, 221, 222 when the short circuit occurs in the circuit. It is set to a number that is less than or equal to the rated breaking capacity. The storage battery modules 211, 212, 221, 222 are connected in parallel to the power supply target 50. As a result, the capacities of the first storage battery group 21 and the second storage battery group 22 can be further improved one by one. In the present embodiment, the plurality of storage batteries included in each storage battery module 211, 212, 221, 222 are lithium ion batteries. In the present embodiment, the capacity of each storage battery module 211, 212, 221, 222 is, for example, about 25 kWh, and the storage capacity of the entire first storage battery group 21 and the second storage battery group 22 is, for example, about 100 kWh. ..

The first thyristor switch SCR1 is a reverse blocking three-terminal type thyristor switch that blocks the flow of current from the power supply target 50 side to the first storage battery group 21 side. The first thyristor switch SCR1 is rendered conductive by the input of the trigger signal to the gate, and supplies power from the first storage battery group 21 side to the power supply target 50 side. Further, the first thyristor switch SCR1 becomes the first thyristor switch SCR1 when the voltage of the power supply target 50 side becomes higher than that of the first storage battery group 21 side in the conductive state and the trigger signal is not input, that is, when the reverse bias is applied. A non-conducting state is established in which the supply of power from the storage battery group 21 side to the power supply target 50 side is cut off. The trigger signal input to the gate of the first thyristor switch SCR1 is generated by the control unit 40. The first thyristor switch SCR1 is provided closer to the first storage battery group 21 side than the circuit breaker 60.

The second thyristor switch SCR2 is a reverse blocking three-terminal type thyristor switch that blocks the flow of current from the power supply target 50 side to the second storage battery group 22 side. The second thyristor switch SCR2 is turned on when a trigger signal is input to the gate, and supplies power from the second storage battery group 22 side to the power supply target 50 side. In addition, the second thyristor switch SCR2 becomes the second when the voltage on the power supply target 50 side is higher than the voltage on the second storage battery group 22 side in the conductive state and the trigger signal is not input, that is, when the reverse bias is applied. A non-conducting state is established in which the power supply from the storage battery group 22 side to the power supply target 50 side is cut off. The trigger signal input to the gate of the second thyristor switch SCR2 is generated by the control unit 40. The second thyristor switch SCR2 is provided closer to the second storage battery group 21 side than the circuit breaker 60. That is, the circuit breaker 60 is provided between the first storage battery group 21 and the second storage battery group 22 and the power supply target 50.

The switching elements S11, S12, S21, S22 are well-known switching elements such as contactors that can be switched on and off. The switching element S11 switches between connection and disconnection of the storage battery module 211 and the first thyristor switch SCR1. The switching element S12 switches between connection and disconnection of the storage battery module 212 and the first thyristor switch SCR1. The switching element S21 switches between connection and disconnection of the storage battery module 221 and the second thyristor switch SCR2. The switching element S22 switches between connection and disconnection of the storage battery module 222 and the second thyristor switch SCR2. The switching elements S11, S12, S21, S22 are on/off controlled by the control unit 40.

The voltage sensor 23 outputs the detected voltage V21 of the first storage battery group 21 to the control unit 40. The voltage sensor 24 outputs the detected voltage V22 of the second storage battery group 22 to the control unit 40. It should be noted that the voltage sensors may be provided one by one to detect the voltages of the storage battery modules 211, 212, 221, 222, respectively.

The third power supply unit 30 converts the AC power from the AC power supply 11 into DC power and supplies the DC power to the first storage battery group 21 and the second storage battery group 22, a charger 31, a first storage battery group 21, and a charger 31. And a switching element S31 provided between the second storage battery group 22 and the second storage battery group 22. The switching element S31 is a known switching element such as a contactor that can be switched on and off, and is on/off controlled by the control unit 40.

Here, the large-capacity storage battery system 1 includes a switching element S32 as a first charging-side switching element that switches between connection and disconnection of the third power supply unit 30 and the first storage battery group 21, and a third power supply unit. 30 and a switching element S33 as a second charging side switching element that switches between connection and disconnection of the second storage battery group 22. The switching element S32 is connected to the switching element S31 of the third power supply unit 30 and the switching elements S11 and S12 of the second power supply unit 20. The switching element S33 is connected to the switching element S31 of the third power supply unit 30 and the switching elements S21 and S22 of the second power supply unit 20. The switching elements S32 and S33 are well-known switching elements such as contactors that can be switched on and off, and are on/off controlled by the control unit 40.

In addition, the large-capacity storage battery system 1 includes a switching element S34 as a first power supply side switching element that switches connection and disconnection between the first power supply unit 10 and the power supply target 50, and one end of the switching element S34 and the power supply target. 50 and the other end is connected between the third power supply unit 30 and the switching element S32 and the switching element S33 to connect and connect the third power supply unit 30 and the power supply target 50. A switching element S35 as a second power supply side switching element for switching between release and release. The switching element S34 and the switching element S35 are well-known switching elements such as contactors that can be switched on and off, and are on/off controlled by the controller 40.

The control unit 40 inputs the value of the voltage V21 of the first storage battery group 21 from the voltage sensor 23 and the value of the voltage V22 of the second storage battery group 22 from the voltage sensor 24. The control unit 40 switches the switching element S11, so that power is uninterruptibly supplied from any one of the first power supply unit 10, the second power supply unit 20, and the third power supply unit 30 to the power supply target 50. ON/OFF control of S12, S21, S22, S31, S32, S33, S34, and S35 is performed, and a trigger signal is output to the first thyristor switch SCR1 and the second thyristor switch SCR2.

In a normal state, that is, when power is supplied from the AC power supply 11 to the power supply target 50, the control unit 40 does not output a trigger signal to the first thyristor switch SCR1 and the second thyristor switch SCR2 and remains in the non-conduction state. The switching element S34 is turned on and the switching element S35 is turned off. As a result, the power from the AC power supply 11 converted into DC power by the rectifier 12 of the first power supply unit 10 is supplied to the power supply target 50.

The control unit 40 supplies the power from the first power supply unit 10 to the power supply target 50 (the switching element S34 is turned on and the switching element S35 is turned off), and the voltage input from the voltage sensor 23 is supplied. Based on the value of the voltage V22 input from V21 or the voltage sensor 24, the switching elements S11, S12, S21, S22 are on/off controlled, and the switching elements S31, S32, S33 are on/off controlled, and the third power supply unit 30 Charging power is supplied to each storage battery module 211, 212, 221, 222. Specifically, the control unit 40 turns on the switching element S31 and decreases the voltage when there is a battery whose voltage is lowered among the storage battery modules 211, 212, 221, 222. One of the switching elements S11, S12, S21, S22 corresponding to the storage battery modules 211, 212, 221, 222, and the switching element S32 or the switching element S33 are turned on. Thereby, the electric power from the AC power supply 11 is supplied via the charger 31 to any of the storage battery modules 211, 212, 221, 222 whose voltage has dropped. When there are a plurality of storage battery modules 211, 212, 221, 222 whose voltage has dropped, charging power may be simultaneously supplied to those whose voltage has dropped.

As described above, when the switching element S32 or the switching element S33 is turned on in the state where the switching element S34 is turned on and the switching element S35 is turned off, the first power supply unit 10 supplies power to the power supply target 50. The charging power can be supplied from the third power supply unit 30 to the first storage battery group 21 or the second storage battery group 22. At this time, the first thyristor switch SCR1 and the second thyristor switch SCR2 prevent the current from the first power supply unit 10 from flowing to the first storage battery group 21 and the second storage battery group 22 side. It is possible to accurately control the charging power supplied from the power supply unit 30 to the first storage battery group 21 or the second storage battery group 22 to a charging current and a charging voltage that match the charging characteristics of the storage battery.

On the other hand, when the control unit 40 does not supply the charging power from the third power supply unit 30 to the first storage battery group 21 and the second storage battery group 22, the control unit 40 keeps the switching element S31 or the switching element S32 and the switching element S33 off. .. That is, in the large-capacity storage battery system 1 of the present embodiment, the third power supply unit 30 and the storage battery modules 211, 212, 221, 222 are separated from each other except when charging is performed. As a result, it is possible to suppress the occurrence of abnormalities that may occur during charging of the lithium-ion battery, and to suppress thermal runaway satisfactorily. Therefore, the safety of the device can be ensured. Furthermore, by not always charging the storage battery modules 211, 212, 221, 222, it is possible to suppress the generation of hydrogen gas or the like from the inside of each storage battery. Since the lithium-ion battery does not easily self-discharge, it is possible to secure sufficient stored power even if the storage battery modules 211, 212, 221, 222 are not always charged.

When performing maintenance and inspection on the rectifier 12 of the first power supply unit 10, the control unit 40 turns off the switching element S34 and turns on the switching elements S31 and S35 so that the third power supply unit 30 operates. The power of the AC power supply 11 is supplied to the power supply target 50. At this time, the control unit 40 turns off the switching elements S32 and S33, and does not allow the third power supply unit 30 to supply the charging power to the first storage battery group 21 and the second storage battery group 22. Accordingly, even when performing maintenance and inspection on the rectifier 12 of the first power supply unit 10, the power from the AC power supply 11 can be supplied to the power supply target 50 via the third power supply unit 30.

When power cannot be supplied from the AC power supply 11 of the first power supply unit 10 to the power supply target 50 in an emergency such as a power failure, the control unit 40, based on the value of the input voltage V21 or voltage V22, the first thyristor. In addition to generating and outputting a trigger signal to the switch SCR1 and the second thyristor switch SCR2, the switching elements S11, S12, S21, and S22 are on/off controlled, and the second power supply unit 20 supplies power to the power supply target 50. Hereinafter, the operation of the large-capacity storage battery system 1 in this case will be described in detail.

FIG. 2 is a schematic diagram showing a state in which the storage battery module 211 included in the first storage battery group 21 and the power supply target 50 are connected in the large capacity storage battery system 1. The control unit 40 sets the switching element S11 corresponding to the storage battery module 211 to the ON state in advance, and when the AC power supply 11 of the first power supply unit 10 cannot supply power to the power supply target 50 due to a power failure or the like, As shown in FIG. 2, a pulsed trigger signal is output to the gate of the first thyristor switch SCR1 corresponding to the first storage battery group 21 including the storage battery module 211 to bring it into a conductive state. As a result, DC power is supplied from the storage battery module 211 to the power supply target 50, as indicated by the solid white arrow in FIG. In this embodiment, since a pulsed signal is used as the trigger signal, it is assumed that the output of the trigger signal from the control unit 40 is stopped after the first thyristor switch SCR1 becomes conductive.

The control unit 40 monitors the voltage V21 of the first storage battery group 21, which is input from the voltage sensor 23, that is, the voltage V21 of the storage battery module 211, while supplying power from the storage battery module 211 to the power supply target 50. deep. When the value of voltage V21 of storage battery module 211 is not lower than or equal to predetermined voltage Vref, control unit 40 continues the state shown in FIG.

When the discharge of the storage battery module 211 progresses and the value of the voltage V21 of the storage battery module 211 becomes equal to or lower than the predetermined voltage Vref, the control unit 40 turns on the switching element S21 corresponding to the storage battery module 221, and the storage battery module 221 and the second The second thyristor switch SCR2 corresponding to the storage battery group 22 is connected. The predetermined voltage Vref is set to a value larger than the switching voltage Vs described later.

When the storage battery module 211 is further discharged and the value of the voltage V21 of the storage battery module 211 becomes equal to or lower than the switching voltage Vs, the control unit 40 outputs a pulse-shaped trigger signal to the gate of the second thyristor switch SCR2, and the second The thyristor switch SCR2 is turned on. In the present embodiment, the switching voltage Vs is the final voltage of the storage battery modules 211, 212, 221, 222. The switching voltage Vs may be a value larger than the final voltage of the storage battery modules 211, 212, 221, 222. As a result, the storage battery module 221 before power supply included in the second storage battery group 22 and the power supply target 50 are connected. FIG. 3 is a schematic diagram showing a state in which the storage battery module 221 included in the second storage battery group 22 and the power supply target 50 are connected in the large capacity storage battery system 1. In this state, supply of electric power from the storage battery module 221 to the power supply target 50 is started as indicated by a white solid arrow in FIG.

Here, the storage battery module 221 immediately after the start of the power supply, in which the voltage has not yet dropped, has a higher voltage than the storage battery module 211, which has reached the switching voltage (the final voltage in this embodiment) Vs. Therefore, when the supply of power from the storage battery module 221 to the power supply target 50 is started, the voltage of the power supply target 50 side of the first thyristor switch SCR1 becomes higher than the voltage of the storage battery module 211 side. Then, as described above, the output of the pulse-shaped trigger signal from the control unit 40 to the first thyristor switch SCR1 is stopped after the first thyristor switch SCR1 becomes conductive, and therefore the storage battery module 211. Is stopped before the voltage V21 of the switch becomes lower than the switching voltage Vs. Therefore, the first thyristor switch SCR1 is automatically brought into a non-conducting state by applying a so-called reverse bias in the conducting state and the state where the trigger signal is not input. As a result, the power supply from the storage battery module 211 to the power supply target 50 is stopped. That is, the large-capacity storage battery system 1 switches the storage battery group that supplies power to the power supply target 50 from the first storage battery group 21 to the second storage battery group 22 simply by outputting the trigger signal to the second thyristor switch SCR2. It becomes possible. Further, in the present embodiment, the storage battery modules 211, 212, 213, 214 have a plurality of storage batteries connected in parallel. However, the first thyristor switch SCR1 and the switching elements S11, S12, Since only the second thyristor switch SCR2 corresponding to the two storage battery group 22 and the switching elements S21 and S22 need be used, it is not necessary to provide switching elements according to the number of parallel storage batteries. Therefore, it is possible to supply power to the power supply target 50 uninterruptibly with a simpler configuration and control.

Further, as described above, in the large-capacity storage battery system 1 of the present embodiment, when the voltage V21 of the storage battery module 211 becomes equal to or lower than the predetermined voltage Vref that is higher than the switching voltage Vs, the switching element corresponding to the storage battery module 221. Turn on S21. Accordingly, when the voltage of the storage battery module 211 becomes equal to or lower than the switching voltage Vs, it is possible to promptly start the supply of electric power from the storage battery module 221 to the power supply target 50 only by outputting the second thyristor switch SCR2. it can. That is, the large-capacity storage battery system 1 can switch the storage battery module that supplies power to the power supply target 50 from the storage battery module 211 to the storage battery module 221 only by outputting the trigger signal to the second thyristor switch SCR2. Become. As a result, the capacities of the first storage battery group 21 and the second storage battery group 22 can be further improved, and the power can be supplied to the power supply target 50 more reliably and uninterrupted by simpler control.

The control unit 40 switches the storage battery module that supplies electric power to the power supply target 50 from the storage battery module 211 to the storage battery module 221, and then the control unit 40 keeps the switching element S11 off and the voltage V22 of the storage battery module 221. Keep an eye on. Then, when the voltage V22 of the storage battery module 221 decreases, the large-capacity storage battery system 1 supplies the power to the power supply target 50 by the same procedure as the switching from the storage battery module 211 to the storage battery module 221. Switches to the storage battery module 212 included in the first storage battery group 21 before power supply. Furthermore, when the voltage V21 of the storage battery module 212 decreases, the large-capacity storage battery system 1 performs the same procedure to supply the power supply target 50 with the storage battery module included in the second storage battery group 22 before the power supply. The storage battery module 222 is switched to. The values of the predetermined voltage Vref and the switching voltage Vs may be different for each storage battery module 211, 212, 221, 222.

As described above, the large-capacity storage battery system 1 has a plurality of storage battery modules 211, 212, 221, 222 connected in parallel to the power supply target 50, and when the AC power supply 11 cannot supply power to the power supply target 50, such as a power failure, Each storage battery module 211, 212, 221, 222 is sequentially connected to the power supply target 50. Thereby, it is possible to sufficiently secure the stored electric power to be supplied to the power supply target 50 in an emergency such as a power failure. In particular, even when a lithium ion battery having a relatively small single cell capacity is used as the storage battery as in this embodiment, it is possible to sufficiently secure the stored power.

Further, the large-capacity storage battery system 1 may disconnect all the storage battery modules 211, 212, 221, and 222 from the power supply target 50 except the storage battery module that is supplying power by sequentially connecting the plurality of storage battery modules 211, 212, 221, and 222 to the power supply target 50. it can. As a result, when the short circuit occurs in any of the circuits while further improving the capacities of the first storage battery group 21 and the second storage battery group 22, the short circuit currents from the plurality of storage battery modules 211, 212, 221, 222. It is possible to suppress the flow of a large short-circuit current due to the combination of the above, and to favorably protect the power supply target 50.

Further, it is not necessary to enhance the breaking performance of the circuit breaker 60 by suppressing the short circuit currents from the storage battery modules 211, 212, 221, 222 from flowing and the large short circuit current from flowing. As a result, a relatively simple (general) breaker can be used as the circuit breaker 60, or existing equipment can be used as it is, so that the cost of the equipment as a whole can be reduced. Further, as described above, the number of parallel storage batteries included in each storage battery module 211, 212, 221, 222 is determined by the short-circuit current from each storage battery module 211, 212, 221, 222 when a short circuit occurs in the circuit. Is set to a number not exceeding the rated breaking capacity of the circuit breaker 60. In this way, the short circuit current that may flow from each of the storage battery modules 211, 212, 221, 222 is supplied to the storage battery modules 211, 212, 221, 222 while preventing the short circuit current from exceeding the rated breaking capacity of the circuit breaker 60. By connecting a plurality of parallel connections to the target, it is possible to sufficiently improve the overall storage capacity of the first storage battery group 21 and the second storage battery group 22 while using a relatively simple (general) circuit breaker 60. Becomes

As described above, according to the large-capacity storage battery system 1 of the present embodiment, in a large-capacity storage battery system in which a plurality of storage batteries are connected in parallel to the power supply target 50, power supply is performed with simpler control while ensuring safety. Power can be supplied to the target 50 uninterruptedly.

In the present embodiment, the second power supply unit 20 includes two storage battery groups (first storage battery group 21 and second storage battery group 22) and two thyristor switches (first thyristor switch SCR1 and second thyristor switch SCR2). However, the second power supply unit 20 may include three or more storage battery groups and three or more thyristor switches corresponding to each storage battery group. Also in this case, each storage battery module included in each storage battery group may be sequentially connected to the power supply target 50 by the procedure described above.

Further, in the present embodiment, the first storage battery group 21 has the storage battery modules 211 and 212, and the second storage battery group 22 has the storage battery modules 221 and 222. However, the first storage battery group 21 and the second storage battery group The storage battery group 22 may include at least one storage battery module, and may include three or more storage battery modules connected in parallel to the power supply target 50. When the first storage battery group 21 and the second storage battery group 22 include only one storage battery module, the switching elements S11, S12, S21, S22 may be omitted. In addition, when only the capacity of the first power storage group 21 is sufficient and the second storage battery group 22 is not required, the second storage battery group 22, the second thyristor switch SCR2, and the switching element S33 may be omitted. When the first storage battery group 21 and the second storage battery group 22 include three or more storage battery modules, a switching element is provided between each storage battery module and the first thyristor switch SCR1 or the second thyristor switch SCR2. It should be provided.

In addition, in the present embodiment, the third power supply unit 30 is separated from the first storage battery group 21 and the second storage battery group 22 except when charging power is supplied from the third power supply unit 30. The third power supply unit 30, the first storage battery group 21, and the second storage battery group 22 may be connected as necessary.

Further, in the present embodiment, the lithium ion battery is used as the storage battery included in the storage battery module 211, 212, 221, 222, but the storage battery may be a nickel hydride battery, an all-solid-state battery, a metal/air battery, an organic secondary battery. , Lithium metal battery, sodium ion battery, magnesium ion battery and aluminum ion battery. Also in this case, according to the large-capacity storage battery system 1, since it is possible to suppress a large short-circuit current from flowing from each storage battery group, it is possible to ensure the safety of the device and increase the storage capacity. You can

In the present embodiment, the control unit 40 outputs a pulse-shaped trigger signal to the gates of the first thyristor switch SCR1 and the second thyristor switch SCR2. However, after the control unit 40 outputs the trigger signal, As long as the output is stopped before the voltage of the storage battery module being fed reaches the switching voltage Vs, the pulsed signal is not necessary.

In addition, in the present embodiment, the control unit 40 causes the first storage battery group 21 including the storage battery module 211 to be in a state where power cannot be supplied from the AC power supply 11 of the first power supply unit 10 to the power supply target 50 due to a power failure or the like. The pulse-shaped trigger signal is output to the gate of the corresponding first thyristor switch SCR1 to make it conductive, but when the output voltage of the rectifier 12 is set higher than the output voltage of the charger 31, the first voltage is set in advance. A trigger signal may be output to the gate of the 1-thyristor switch SCR1.

Accordingly, when the charging power is supplied from the charger 31 (third power supply unit 30) to the first storage battery group 21 while supplying power to the power supply target 50 from the rectifier 12 (first power supply unit 10). In addition, the first thyristor switch SCR1 is applied with the reverse bias voltage to maintain the non-conduction state. As a result, the power from the charger 31 (third power supply unit 30) is not supplied to the power supply target 50 side, and the charging power can be satisfactorily supplied to the first storage battery group 21. Then, since the trigger signal is output to the first thyristor switch SCR1 in advance, the first thyristor switch SCR1 outputs the output of the rectifier 12 in an emergency when power from the AC power supply 11 cannot be supplied to the power supply target 50 such as a power failure. As the voltage decreases, the reverse bias voltage is immediately turned on at the timing when the application of the reverse bias voltage is stopped. As a result, in the event of an emergency such as a power failure, it is possible to promptly start power supply from the storage battery module 211 to the power supply target 50. It is assumed that the output of the trigger signal from the control unit 40 is stopped after the first thyristor switch SCR1 becomes conductive due to the decrease in the output voltage of the rectifier 12 due to a power failure or the like.

Further, in the present embodiment, the charging power is supplied from the third power supply unit 30 to the first storage battery group 21 and the second storage battery group 22, but the charging characteristics of the storage battery, the charging voltage of the rectifier 12, and the charging current. In consideration of the controllability of the third power supply unit 30 (charger 31 and switching element S31), the first power supply unit 10 (rectifier 12) supplies power to the power supply target 50 and the first storage battery. Both charging power may be supplied to the group 21 and the second storage battery group 22. In this case, when the switching element 34 is turned on and the switching element 35 is turned off, power is supplied from the first power supply unit 10 to the power supply target 50, and charging power for the first storage battery group 21 and the second storage battery group 22 is supplied. Supply can be stopped.

1 Large Capacity Storage Battery System 10 First Power Supply Unit 11 AC Power Supply 12 Rectifier 20 Second Power Supply Unit 21 First Storage Battery Group 22 Second Storage Battery Group 211, 212, 221, 222 Storage Battery Module 23, 24 Voltage Sensor 30 Third Power Supply unit 31 Charger 40 Control unit 50 Power supply target 60 Circuit breaker S11, S12, S21, S22, S31, S32, S33, S34, S35 Switching element SCR1 First thyristor switch SCR2 Second thyristor switch

Claims (5)

Have a plurality of storage batteries, see contains a plurality of first accumulator module connected in parallel to the power supply target, a first battery group connected to the power supply object,
Have a plurality of storage batteries, and the power supply object to look including a plurality of second battery modules connected in parallel, the second battery group connected in parallel with the first battery group to the power supply object,
When a trigger signal is input, the first storage battery group is brought into a conducting state for supplying electric power to the power supply target, and a reverse bias voltage is applied in the conducting state and in a state where the trigger signal is not inputted. And a first thyristor switch in a non-conducting state that cuts off the supply of electric power from the first storage battery group to the power supply target,
When a trigger signal is input, the second storage battery group is brought into a conducting state for supplying electric power to the power supply target, and a reverse bias voltage is applied in the conducting state and in a state where the trigger signal is not inputted. And a second thyristor switch in a non-conducting state that cuts off the supply of electric power from the second storage battery group to the power supply target,
A controller that outputs the trigger signal to the first thyristor switch and the second thyristor switch;
A plurality of first switching elements that are on/off controlled by the control unit and switch between connection and disconnection of each of the first storage battery modules and the first thyristor switch;
A plurality of second switching elements that are on/off controlled by the control unit and switch between connection and disconnection of each of the second storage battery modules and the second thyristor switch;
Equipped with
The control unit is
One of the first switching elements is turned on and the trigger signal is output to the first thyristor switch to bring the first thyristor switch into the conductive state, thereby setting the first storage battery module included in the first storage battery group . Power is supplied from one to the power supply target,
Output of the trigger signal to the first thyristor switch is stopped before the voltage of the first storage battery module during power supply becomes equal to or lower than the switching voltage,
When the voltage of the first storage battery module during power supply becomes equal to or lower than a predetermined voltage higher than the switching voltage, the second switching element corresponding to one of the second storage battery modules before power supply, Turn it on,
When the voltage of the first storage battery module during the power supply becomes equal to or lower than the switching voltage, the trigger signal is output to the second thyristor switch to make the second thyristor switch conductive, and the second thyristor switch is turned on. mass storage battery system characterized by to supply the power and to the power supply object from one of the second battery module before the power supply included in the battery group. A charging power supply unit that supplies charging power to the first storage battery group and the second storage battery group;
A first charging side switching element that is on/off controlled by the control unit and switches between connection and disconnection of the first storage battery group and the charging power supply unit;
A second charging side switching element that is on/off controlled by the control unit and switches between connection and disconnection of the second storage battery group and the charging power supply unit;
The control unit turns off the first charging side switching element and the second charging side switching element when the charging power supply section does not supply charging power to the first storage battery group and the second storage battery group. The large-capacity storage battery system according to claim 1 . A power source power supply unit that supplies power from a power source different from those of the first storage battery group and the second storage battery group to the power supply target;
A first power supply side switching element which is on/off controlled by the control unit and switches between connection and disconnection of the power source power supply unit and the power supply target;
On/off control is performed by the control unit, one end is connected between the first power feeding side switching element and the power feeding target, and the other end is the charging power supply unit, the first charging side switching element, and the second charging. A second power supply side switching element connected between the charging power supply section and the power supply target, the second power supply side switching element being connected between the charging power supply section and the power supply target;
Further equipped with,
The control unit is
When supplying power from the power supply unit to the power supply target, the first power supply side switching element is turned on and the second power supply side switching element is turned off,
The large-capacity storage battery system according to claim 2 , wherein the first power supply side switching element is turned off and the second power supply side switching element is turned on when performing maintenance and inspection of the power source power supply unit. Further comprising a circuit breaker provided between the first storage battery group and the second storage battery group and the power supply target,
When connecting the plurality of storage batteries in parallel to the power supply target in the first storage battery module and the second storage battery module, the parallel number of the storage batteries is the short-circuit current from the first storage battery module or the second storage battery module. If the flows, large capacity battery system according to any one of claims 1 to 3, wherein the short-circuit current is a number that is less than the rated breaking capacity of the circuit breaker. The storage battery is any one of a lithium ion battery, a nickel hydrogen battery, an all-solid battery, a metal/air battery, an organic secondary battery, a lithium metal battery, a sodium ion battery, a magnesium ion battery, and an aluminum ion battery. The large-capacity storage battery system according to any one of claims 1 to 4 .

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