KR20180113409A - Power storage apparatus and method for controling the same - Google Patents

Abstract

Provided are a power storage apparatus and a control method thereof for interrupting a current of a battery in an abnormal state. According to one embodiment of the present invention, the power storage apparatus comprises: a plurality of battery groups arranged to be in mutually parallel connection and having a cathode commonly connected to a second integrated power line; a plurality of battery management systems individually monitoring states of the battery groups; a plurality of sub power lines interconnecting a first electrode of two battery groups adjacent to each other among the battery groups; a plurality of main power lines having one end connected to the sub power lines on a one-to-one basis and the other end commonly connected to a first integrated power line; and a plurality of breakers installed on each connection node of the sub power lines and the main power lines.

Description

[0001] POWER STORAGE APPARATUS AND METHOD FOR CONTROLLING THE SAME [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power storage device and a method of controlling the same, and more particularly, to a device including a plurality of batteries arranged in parallel to each other and a method of controlling the device to protect a plurality of batteries from transients .

2. Description of the Related Art In recent years, demand for portable electronic products such as notebook computers, video cameras, and portable telephones has rapidly increased, and electric vehicles, storage batteries for energy storage, robots, and satellites have been developed in earnest. Researches are being actively conducted.

Currently, commercialized batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium batteries. Among them, lithium batteries have little memory effect compared to nickel-based batteries, And is attracting attention because of its high energy density.

A power storage device includes a plurality of batteries and is used to supply stable power to a load in various fields related to an uninterruptible power supply, a power conversion device, and the like.

In this case, at least some of the plurality of batteries included in the power storage device are required to be connected in parallel. During operation of the power storage device, when at least one of the batteries included therein is in an abnormal state, it is necessary to electrically isolate the battery in an abnormal state from the remaining battery. As a patent document disclosing related art related thereto, Korean Patent Laid-Open Publication No. 10-2014-0059909 (published on May 19, 2014) is known. The patent document discloses a technique of reducing a transient current due to a voltage difference between batteries using a breaker connected between an inverter and a first electrode of each of a plurality of batteries.

However, if the current to some of the plurality of batteries is cut off while the magnitude of the current flowing from any one of the load and the power storage device is kept constant, all the currents are discharged to the remaining battery, There is a problem that serious damage is caused in the power storage device.

The present invention has been conceived to solve the above-mentioned problems, and it is an object of the present invention to prevent a situation in which a current of a battery which is in an abnormal state is blocked while a transient current flows in the remaining battery And a control method thereof.

Other objects and advantages of the present invention will become apparent from the following description, and it will be understood by those skilled in the art that the present invention is not limited thereto. It is also to be understood that the objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations thereof.

Various embodiments of the present invention for achieving the above object are as follows.

A power storage device according to an aspect of the present invention includes: a plurality of battery groups arranged in parallel to each other and having cathodes commonly connected to a second integrated power line; A plurality of battery management systems that individually monitor states of the plurality of battery groups; A plurality of sub power lines interconnecting first electrodes of two adjacent battery groups among the plurality of battery groups; A plurality of main power lines, one end of which is connected to the plurality of sub power lines on a one-to-one basis and the other end is commonly connected to a first integrated power line; And a plurality of breakers provided for each of the plurality of sub power lines and the connection nodes of the plurality of main power lines. Each of the battery management systems outputs a current shutoff signal for turning off at least two of the plurality of circuit breakers when a state of a battery group designated to itself among the plurality of battery groups is determined to be a predetermined abnormal state do.

Each of the battery management systems may determine that the battery group assigned to the battery management system is in an abnormal state when the voltage of the battery group designated to itself is equal to or lower than a predetermined discharge end voltage.

Each of the battery management systems may determine that the battery group designated in the battery management system is in an abnormal state when the SOH of the battery group designated to itself is equal to or less than a predetermined threshold SOH.

Each of the battery management systems may determine that the battery group assigned to the battery management system is in an abnormal state when the current of the battery group designated to itself is equal to or greater than a predetermined threshold current.

The controller may further include a plurality of controllers provided on the plurality of circuit breakers on a one-to-one basis. In this case, each of the controllers may turn off one of the circuit breakers assigned to itself when receiving the current interruption signal.

In addition, each of the battery management systems, when it is determined that the state of any one of the battery groups designated to the battery management system is a predetermined abnormal state, is connected to the connection nodes of two sub power lines connected to the first electrode of one battery group The current cutoff signal can be outputted to the two breakers installed.

The battery management system may further include an integrated controller configured to individually communicate with the plurality of battery management systems. Wherein the integrated controller includes: a number of battery groups electrically connected to the first and second integrated power lines of the plurality of battery groups; And a current value of the first and second integrated power lines; and setting signals indicating the target number to the plurality of battery management systems individually.

Each of the battery management systems may further cause the circuit breaker corresponding to the target number of the plurality of circuit breakers to perform the current shutoff in accordance with the setting signal when a state of any one of the battery groups designated to the battery management system is determined to be a predetermined abnormal state, Signal can be transmitted.

According to at least one embodiment of the present invention, when a part of a plurality of batteries included in the power storage device is in an abnormal state, a state in which the current of the battery that is in an abnormal state is shut off, can do.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the description of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate preferred embodiments of the invention and, together with the description of the invention given below, serve to further the understanding of the technical idea of the invention. And should not be construed as limiting.
1 is a schematic view showing a configuration of a power storage device according to an embodiment of the present invention.
FIG. 2 illustrates a configuration in which six battery groups are included in the power storage device of FIG.
FIG. 3 and FIG. 4 are diagrams for explaining the operation when some of the battery groups in FIG. 2 are in an abnormal state.
5 is a simplified view of the power storage device of FIG.
Figs. 6 to 8 are diagrams for explaining the operation in the case where any battery group of the power storage device of Fig. 5 is in an abnormal state.
9 is a flowchart showing a method of controlling a power storage device according to another embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the inventor should appropriately interpret the concepts of the terms appropriately It should be construed as meaning and concept consistent with the technical idea of the present invention based on the principle that it can be defined.

Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, It is to be understood that equivalents and modifications are possible.

In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

Terms including ordinals, such as first, second, etc., are used for the purpose of distinguishing one of the various components from the rest, and are not used to define components by such terms.

Throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements, not excluding other elements unless specifically stated otherwise. In addition, the term " control unit " as described in the specification means a unit for processing at least one function or operation, and may be implemented by hardware or software, or a combination of hardware and software.

In addition, throughout the specification, when a portion is referred to as being "connected" to another portion, it is not necessarily the case that it is "directly connected", but also "indirectly connected" .

1 is a schematic view showing a configuration of a power storage device 100 according to an embodiment of the present invention.

1, a power storage device 100 includes a plurality of battery groups B, a plurality of battery management systems (BMS), a plurality of sub power lines SL, a plurality of main power lines ML, A breaker CB and an integrated control unit 300. [ Alternatively, the power storage device 100 may further include at least one of the current sensor 210 and the voltage sensor 220. Hereinafter, it is assumed that '#' is used to distinguish among a plurality of configurations which are in the same role. For example, when there are several configurations of 'A', 'A # X' means 'X' among the plurality of 'A'.

The power storage device 100 may include N battery groups B # 1 to B # N. N is an integer of 2 or more. Each battery group B includes at least one battery cell. When a plurality of battery cells are included in each battery group B, the plurality of battery cells may be connected to each other in parallel and / or in series. The battery groups B # 1 to B # N are arranged so that they can be connected in parallel with each other.

The power storage device 100 may include N battery management systems (BMS # 1 to BMS # N). Each battery management system (BMS) is assigned one-to-one to a plurality of battery groups B # 1 to B # N. Each battery management system (BMS) monitors the state of one battery group B assigned to itself. For example, each battery management system (BMS) detects a parameter (e.g., current, voltage, temperature, SOC and / or SOH) of one battery group B assigned to itself at a predetermined time period, Parameters to another battery management system (BMS) or the integrated control unit 300. [ Each battery management system (BMS) can communicate with another battery management system (BMS).

Each battery management system (BMS) can determine whether the corresponding battery group B is in an abnormal state, based on the monitored parameters from any one of the battery groups B assigned thereto. For example, when the temperature of the i-th battery group B # i is lower than or equal to the first threshold temperature or higher than the second threshold temperature higher than the first threshold temperature, the i-th battery management system BMS # It can be determined that the group B # i is in an abnormal state. As another example, when the voltage of the ith battery group B # i is equal to or higher than a predetermined discharge end voltage or higher than the charge end voltage higher than the discharge end voltage, the i-th battery management system BMS # B # i) can be determined to be in an abnormal state. As another example, when the SOH (State Of Health) of the i-th battery group B # i is equal to or less than a predetermined threshold SOH, the i-th battery group B # State. Alternatively, the i-th battery management system (BMS # i) can determine that the ith battery group B # i is in an abnormal state when the current of the ith battery group B # i is equal to or greater than a predetermined threshold current have. Each battery management system BMS can be transmitted to the integrated control unit 300 with an identifier of the battery group G determined to be in an abnormal state when the battery group G assigned to itself is determined to be in an abnormal state.

Further, each battery management system (BMS) controls charging / discharging of one battery group B designated to itself. Thus, individual monitoring and charge / discharge control of the plurality of batteries B # 1 to B # N is possible.

Each of the battery management systems BMS is configured to turn off at least one of the plurality of circuit breakers CB # 1 to CB # N based on a result of the determination as to whether a certain battery group B designated to itself is in an abnormal state. The current blocking signal can be outputted. Preferably, each of the battery management systems (BMS) is configured to turn off at least two of the plurality of circuit breakers CB # 1 to CB # N when it is determined that a certain battery group B designated to itself is in an abnormal state A current shutoff signal can be output.

The power storage device 100 may include N sub power lines SL # 1 to SL # N. Each sub power line SL electrically connects the first electrodes of two adjacent battery groups among the plurality of battery groups B # 1 to B # N. The first electrode refers to either the positive electrode or the negative electrode of the battery group (B). For example, one end and the other end of the k-th sub power line SL # k are connected to the node (PN # 1) corresponding to the first electrode of the k-th battery group B # (PN # k + 1) corresponding to the first electrode of the first node (B # k + 1). Of course, one end and the other end of the Nth sub power line SL # N are connected to the node (PN # N) corresponding to the first electrode of the Nth battery group B # N and the node (PN # 1) corresponding to the first electrode of the first transistor (e.g., transistor).

One of two ends of the plurality of sub power lines SL # 1 to SL # N is electrically connected to the first electrode of one of the battery groups B via the same node PN. For example, one end of the p-th sub power line SL # p and one end of the (p + 1) th sub power line SL # p + 1 are connected to each other through the p-th node PN # p + And is electrically connected to the first electrode of the +1 battery group B # p + 1. Of course, one end of the Nth sub power line SL # N and one end of the first sub power line SL # 1 are connected to each other through the first node PN # It can be easily understood by those skilled in the art that it can be electrically connected to one electrode.

The power storage device 100 may include N main power lines ML # 1 to ML # N. One end of each main power line ML may be electrically connected to the plurality of sub power lines SL # 1 to SL # N on a one-to-one basis. For example, the mth main power line ML # m may be electrically connected to the mth sub power line SL # m on a one-to-one basis. That is, each main power line ML is electrically connected to one point of any one of the plurality of sub power lines SL # 1 to SL # N.

The other ends of the plurality of main power lines ML # 1 to ML # N may be commonly connected to the first integrated power line HL via the integration node CN. As shown, the second electrodes of the plurality of battery groups B # 1 to B # N can be connected in common to the second integrated power line LL through the integration node NN. The second electrode is different from the first electrode of the positive electrode and the negative electrode of the battery group (B). The first and second integrated power lines HL LL may be electrically connected to the uninterruptible power supply unit, the power conversion unit, and the like. Hereinafter, it is assumed that the first electrode is the anode and the second electrode is the cathode, as shown in FIG.

The power storage device 100 may include N breakers CB # 1 to CB # N. Each of the breakers CB is provided for each of the connection nodes of the plurality of sub power lines SL # 1 to SL # N and the plurality of main power lines ML # 1 to ML # N. Each circuit breaker CB transitions from a turn-on state to a turn-off state in response to a current cutoff signal from the outside. When the circuit breaker CB is turned off, no current can flow through the connection node provided with the circuit breaker CB. That is, each of the breakers CB can cut off the current of the sub power line SL and the main power line ML electrically connected thereto.

Each circuit breaker CB may be provided with a controller. That is, a plurality of controllers may be provided one-to-one in the plurality of breakers CB # 1 to CB # N. Each of the controllers receives a current cutoff signal from the outside, and turns off the circuit breaker CB provided in accordance with the received current cutoff signal. For example, when the current cutoff signal output by any one of the plurality of battery management systems (BMS # 1 to BMS # N) is transmitted to the controller of the hth circuit breaker CB # h, the hth circuit breaker CB # The controller of h) turns off the h-th breaker CB # h. As a result, the current of the control main power line (ML # h) is cut off.

The current sensor 210 senses the direction and magnitude of the current flowing through the first and second integrated power lines HL and LL and integrates the first monitoring signal S1 indicating the direction and magnitude of the sensed current To the control unit 300. The voltage sensor 220 detects a potential difference between the first integrated power line HL and the second integrated power line LL and transmits a second monitoring signal S2 indicating the sensed potential difference to the integrated controller 300 .

The integrated control unit 300 is connected to the plurality of battery management systems (BMS # 1 to BMS # N) so as to be able to communicate separately. Optionally, the integrated controller 300 is communicably coupled to at least one of the current sensor 210 and the voltage sensor 220. [ The integrated control unit 300 includes at least one input port and at least one output port. Each input port is connected to the battery management system (BMS # 1 to BMS # N), the breakers CB # 1 to CB # N, the current sensor 210 and / do. Each battery management system (BMS) may transmit to the integrated control unit 300 a signal S3 indicating whether the battery group B is abnormal or not. Each output port is connected to be individually communicable with the battery management systems BMS # 1 to BMS # N and / or the breakers CB # 1 to CB # N.

For example, the first input port I1 is used to receive the signal S1 from the current sensor 210 and the second input port I2 is used to receive the signal S2 from the voltage sensor 220, The third input port I3 is used to receive the signal S3 from the battery management system BMS # 1 to BMS # N, and the first output port OUT1 is used to receive the signal S3 from the battery management system Is used to transmit the signal S4 to the battery management systems BMS # 1 to BMS # N and the second output port OUT2 transmits the signal S5 to the breakers CB # 1 to CB # . In this case, the integrated control unit 300 receives a signal corresponding to the direction and magnitude of the current sensed by the current sensor 210 from the current sensor 210 through the first input port, Receives signals corresponding to the potential difference sensed by the voltage sensor 220 from the sensor 220 and receives the signals corresponding to the battery groups B # 1 to B # N from the battery management systems BMS # 1 to BMS # N via the third input port. #N) can receive signals corresponding to the respective abnormal states. The signal S3 may include data indicating whether each battery group B is electrically connected to the first and second integrated power lines HL and LL. Further, the signal S3 may include an identifier of the battery group G determined to be in an abnormal state. The signal S4 may be a setting signal to be described later. The signal S5 may be a current interruption signal to be described later.

The integrated control unit 300 may be implemented in hardware as application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays Processors, microprocessors, and other electronic units for performing other functions.

The integrated control unit 300 may include a memory. The memory may store data, commands and software required for the overall operation of the power storage device 100. [ In addition, the allowable current value of each battery group B can be stored. The allowable current values of all the battery groups may be equal to each other. Of course, when a deviation occurs between the battery groups depending on the use environment of the power storage device 100, the allowable current value of one of the battery groups may be different from at least one of the remaining battery groups. The integrated control unit 300 refers to the data and commands stored in the memory or drives the software to control the operation of the battery management systems BMS # 1 to BMS # N and the breakers CB # 1 to CB # N Generating, and / or outputting the data for the mobile terminal.

Such a memory may be a flash memory type, a hard disk type, a solid state disk type, an SDD type (Silicon Disk Drive type), a multimedia card micro type, At least one of a random access memory (RAM), a static random access memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), and a programmable read- Type storage medium.

Hereinafter, 'X' is marked on the circuit breaker CB shown in FIG. 3 or the like, which means that the circuit breaker CB is in a turned off state.

FIG. 2 illustrates a configuration in which six battery groups are included in the power storage device 100 of FIG. 1, and FIGS. 3 and 4 illustrate operations when some of the battery groups of FIG. 2 are in an abnormal state Fig.

Referring to FIG. 2, six battery groups B # 1 to B # 6 are connected in parallel to each other through six sub power lines SL # 1 to SL # 6. Both ends of each sub power line SL are electrically connected between two adjacent nodes of the nodes PN # 1 to PN # 6. One of two adjacent nodes corresponds to one of the six battery groups B # 1 to B # 6, and the other corresponds to one of the six battery groups B # 1 to B # 6 Corresponds to the anode.

At this time, each battery management system (BMS) transmits a current cutoff signal to at least two of the plurality of breakers CB # 1 to CB # 6 when the battery group B designated to itself is determined to be in an abnormal state . Preferably, each battery management system (BMS) includes two breakers CB installed in each of two sub-power lines SL electrically connected to a node PN corresponding to the anode of the battery group B assigned to it, Lt; / RTI >

FIG. 3 illustrates a case where the first battery group B # 1 among the six battery groups B # 1 to B # 6 shown in FIG. 2 is in an abnormal state. The first battery management system BMS # 1 determines whether or not the first node PN # 1 corresponding to the positive polarity of the first battery group B # 1, according to the result of the determination that the first battery group B # (CB # 1) and the sixth circuit breaker (CB # 6) provided in the first sub power line (SL # 1) and the sixth sub power line (SL # Can be transmitted. When the first breaker CB # 1 and the sixth breaker CB # 6 are turned off in response to the current cutoff signal, the first main power line ML # 1 and the sixth main power line ML # The current is cut off. Thus, the first to sixth battery groups B # 1 and B # 2 maintain the parallel connection state, while the second to sixth battery groups B # 2 to B # B # 6).

Of course, if the first battery group B # 1 is determined to be in an abnormal state, the first battery management system BMS # 1 may select the first breaker CB # 1 and the sixth breaker CB # 6 to the at least one circuit breaker CB.

FIG. 4 illustrates a case where the second battery group B # 2 among the five battery groups B # 2 to B # 6 in FIG. 3 is additionally determined to be in an abnormal state. The second battery management system BMS # 2 determines whether or not the second node PN # 2 corresponding to the anode of the second battery group B # 2, according to the result of the determination that the second battery group B # The second breaker CB # 2 and the first breaker CB # 1 provided in the second sub power line SL # 2 and the first sub power line SL # 1 electrically connected to the first breaker CB # A blocking signal can be transmitted. 3, the second battery management system BMS # 2 may not transmit the current cutoff signal to the first breaker CB # 1, because the first breaker CB # 1 is already turned off as shown in FIG. 3 . When the second breaker CB # 2 is turned off in response to the current cutoff signal, the current of the second main power line ML # 2 is cut off. Accordingly, the third to sixth battery groups B # 3 to B # 6 maintain the parallel connection state, while the second battery group B # B # 6).

5 is a simplified view of the power storage device 100 of FIG. 4, and FIGS. 6 to 8 illustrate an operation when a battery group of the power storage device 100 of FIG. 5 is in an abnormal state Fig.

4, since the first and second battery groups B # 1 and B # 2 are electrically separated from the power storage device 100, the third to sixth battery groups B # 3 to B # 6) can be simplified to be connected in parallel between the first integrated power line HL and the second integrated power line LL.

Meanwhile, the integrated control unit 300 monitors the number of battery groups B electrically connected to the power storage device 100 at predetermined time intervals while performing individual communication with the battery management systems. 5, the integrated controller 300 determines that four (B # 3 to B # 6) of the battery groups B # 1 to B # 6 of the power storage device 100 are currently electrically connected .

The integrated control unit 300 is configured to control the current flowing through the first integrated power line HL and the second integrated power line HL based on (i) a current value corresponding to a signal from the current sensor 210 Sets a target number based on the number of battery groups B (hereinafter, referred to as a 'reference number') currently electrically connected between the power storage device LL and the current battery 100 To the battery management system (BMS) of the battery group B that is electrically connected to the battery group B. For example, in the situation shown in FIG. 5, the reference number monitored by the integrated control unit 300 is four.

Preferably, the integrated control unit 300 can set the target number based on a result of the determination on any one of the second condition and the third condition while the first condition below is satisfied.

First condition: reference number ≥ 2

Second condition: (reference current value)> (reference number - 1) x (allowable current value)

Third condition: (reference current value)> (reference number - 2) x (allowable current value)

The fact that the first condition is not satisfied means that the reference number is zero. In detail, (i) two adjacent battery groups (e.g., B # 1 and B # 2) are electrically connected to each other through a single sub power line (e.g., SL # 1) SL # 1) can be opened or closed by a single circuit breaker (e.g., CB # 1), so that there is no case where the reference number is 1.

The integrated control unit 300 is connected to two sub power lines (e.g., SL # 2) electrically connected to a node (e.g., PN # 3) corresponding to a first electrode of a battery group (e.g., B # (E.g., CB # 3) of the two breakers (e.g., CB # 2 and CB # 3) installed in each of the first to third circuit breakers SL and SL # 3 are turned on. On the other hand, the integrated control unit 300 has two sub power lines electrically connected to the node (for example, PN # 4) corresponding to the first electrode of the battery group (for example, B # 4) # 3, and SL # 4) are turned on, it is determined whether or not the third condition is satisfied.

Figures 6-8 can be referenced to describe operations related to the target number.

6 illustrates a case where it is determined that the third battery group B # 3 in FIG. 5 is additionally in an abnormal state when the reference current value is 1000A and the allowable current value is 500A. Since the reference number is 4, the first condition is satisfied. The second sub power line SL # 2 and the third sub power line SL # 3 electrically connected to the node (PN # 3) corresponding to the first electrode of the third battery group B # 3 Only the third breaker CB # 3 among the second breaker CB # 2 and the third breaker CB # 3 installed in the integrated circuit 300 is turned on so that the integrated controller 300 can not satisfy the second condition ≪ / RTI > 1000A ≤ (4-1) x (500A), it is determined that the second condition is not satisfied.

If the first condition is satisfied but the second condition is not satisfied, the integrated control unit 300 sets the target number to 2. Therefore, the third battery management system (BMS # 3) is installed in the second sub power line SL # 2 and the third sub power line SL # 3 electrically connected to the third node PN # 3, respectively The current cutoff signal can be transmitted only to the second breaker CB # 2 and the third breaker CB # 3. Since the second breaker CB # 2 has already been turned off (see FIG. 4), when the third breaker CB # 3 is turned off in response to the current cutoff signal, the third main power line ML # Is cut off. Thus, the third battery group B # 3 is electrically separated from the first and second integrated power lines HL and LL. In accordance with the electrical separation of the third battery group B # 3, the integrated control unit 300 can update the reference number to 3.

7 illustrates a case where it is determined that the fourth battery group B # 4 in FIG. 5 is additionally in an abnormal state when the reference current value is 1000A and the allowable current value is 500A. Since the reference number is 4, the first condition is satisfied. The third sub power line SL # 3 and the fourth sub power line SL # 4, which are connected to the node (PN # 4) corresponding to the first electrode of the fourth battery group B # Since the third circuit breaker CB # 3 and the fourth circuit breaker CB # 4 are both turned on, the integrated controller 300 determines whether the third condition is satisfied instead of the second condition. 1000A ≤ (4 - 2) x (500A), it is determined that the third condition is not satisfied.

If the first condition is satisfied but the second condition is not satisfied, the integrated control unit 300 sets the target number to 2. Therefore, the fourth battery management system (BMS # 4) is installed in the third sub power line SL # 3 and the fourth sub power line SL # 4 electrically connected to the fourth node PN # 4, respectively The current interruption signal can be transmitted to the third and fourth circuit breakers CB # 3 and CB # 4. When the third breaker CB # 3 and the fourth breaker CB # 4 are individually turned off in response to the current cutoff signal, the third main power line ML # 3 and the fourth main power line ML # Is cut off. Accordingly, the fourth battery group B # 4 is electrically disconnected from the first and second integrated power lines HL and LL as well as the third battery group B # 3. In accordance with the electrical separation of the third and fourth battery groups B # 3 and B # 4, the integrated control unit 300 can update the reference number to two.

8 illustrates a case where it is determined that the fifth battery group B # 5 of FIG. 5 is additionally in an abnormal state when the reference current value is 1000A and the allowable current value is 480A, unlike FIG. The allowable current value can be periodically updated in accordance with the SOH of each battery group (B). For example, the allowable current value may decrease in response to a decrease in SOH.

Since the reference number is 4, the first condition is satisfied. The fourth sub power line SL # 4 and the fifth sub power line SL # 5 electrically connected to the node (PN # 5) corresponding to the first electrode of the fifth battery group B # 5 The integrated controller 300 determines that the third condition is satisfied instead of the second condition because both the fourth circuit breaker CB # 4 and the fifth circuit breaker CB # 5 are turned on. 1000A > (4 - 2) x (480A), it is determined that the third condition is satisfied.

The integrated control unit 300 sets the target number when both the first condition and the third condition are satisfied. In this case, the integrated control unit 300 can set the target number to be equal to the reference number. Then, the integrated control unit 300 may generate a setting signal indicating the set target number, and then transmit the generated setting signal to the fifth battery management system (BMS # 5). The setting signal may include identification information of each of the breakers CB # 3 to CB # 5 to which the current interruption signal is transmitted.

Therefore, the fifth battery management system (BMS # 5) can control the third and fourth circuit breakers CB # 4 and CB # 5 in accordance with the setting signal from the integrated control unit 300, # 3). ≪ / RTI > When the third to fifth breakers CB # 3 to CB # 5 are individually turned off in response to the current cutoff signal, the currents of the third to fifth main power lines ML # 3 to ML # 5 are cut off . Thereby, none of the battery groups B electrically connected between the first integrated power line HL and the second integrated power line LL remain. Accordingly, the integrated control unit 300 can update the reference number to zero.

9 is a flowchart showing a method of controlling a power storage device according to another embodiment of the present invention. The method shown in Fig. 9 can be executed every time a predetermined time period comes. Alternatively, the method shown in Fig. 9 can be executed whenever at least one battery group is determined to be in an abnormal state.

Referring to FIG. 9, in step 900, the integrated control unit 300 determines a reference number. The integrated control unit 300 determines which of the battery groups B # 1 to B # N of the power storage device 100 and how many of them are connected to the first integrated power line HL, It can be determined whether it is currently electrically connected between the power lines LL. For example, in FIG. 1, if all the battery groups of the power storage device 100 are normally operated, the reference number determined through step 900 will be N. As another example, in FIG. 1, if only the fourth to N-th battery groups B # 4 to B # N are normally operated, the reference number determined through step 900 will be N-3.

In step 910, the integrated control unit 300 determines whether or not the first condition is satisfied. If the determination result of step 910 is "YES ", step 920 is proceeded. If the determination result of step 910 is "NO ", the method ends.

In step 920, the integrated controller 300 determines a reference current value. The integrated controller 300 can determine the reference current value that is the magnitude of the current flowing through the first and second integrated power lines HL and LL based on the signal I1.

In step 930, the integrated control unit 300 determines which one of the battery groups corresponding to the reference number determined through step 900 is in an abnormal state. For example, based on the signal S3 received after step 900, the integrated control unit 300 can check which one of the battery groups G corresponding to the reference number is determined to be in an abnormal state . If the determination result of step 930 is "YES ", step 940 is proceeded. If the determination result of step 930 is "NO ", the method may return to step 920. [

In step 940, the integrated control unit 300 determines in step 930 which of the two breakers associated with the battery group G determined to be in an abnormal state is in the turned off state. That is, the integrated controller 300 determines whether any one of the two breakers installed in each of the two sub-power lines electrically connected to the node (PN) corresponding to the first electrode of one of the battery groups G determined to be in an abnormal state, Off state and the other is turned on. If the determination result of step 940 is "YES ", step 950 proceeds. If the determination result of step 940 is "NO ", step 960 proceeds.

In step 950, the integrated control unit 300 determines whether or not the second condition is satisfied. If the determination result of step 950 is "YES ", step 972 is proceeded. If the determination result of step 950 is "NO ", step 974 is proceeded.

In step 960, the integrated control unit 300 determines whether or not the third condition is satisfied. If the determination result of step 960 is "YES ", step 972 is proceeded. If the determination result of step 960 is "NO ", step 974 is proceeded.

In step 972, the integrated control unit 300 sets the target number to be equal to the reference number.

In step 974, the integrated control unit 300 sets the target number to two.

In step 980, the integrated control unit 300 may transmit a setting signal indicating the target number. The setting signal transmitted through step 980 may be received by the battery management system (BMS) assigned to the battery group G determined to be in an abnormal state through step 930.

When the target number is set to be equal to the reference number, the battery management system (BMS), which has received the setting signal, can transmit a current cutoff signal to all the breakers CB that are currently turned on.

When the target number is set to 2, the battery management system (BMS) receiving the setting signal transmits the current cutoff signal only to the two circuit breakers associated with the battery group G assigned to itself. For example, in FIG. 5, when the third battery management system (BMS # 3) receives the setting signal, a current cutoff signal may be transmitted only to the second breaker CB # 2 and the third breaker CB # 3.

According to the power storage device 100 and the control method thereof according to the embodiments of the present invention described above with reference to Figs. 1 to 9, only one battery group G is connected to the first and second integrated power lines HL , And LL).

The embodiments of the present invention described above are not only implemented by the apparatus and method but may be implemented through a program for realizing the function corresponding to the configuration of the embodiment of the present invention or a recording medium on which the program is recorded, The embodiments can be easily implemented by those skilled in the art from the description of the embodiments described above.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not to be limited to the details thereof and that various changes and modifications will be apparent to those skilled in the art. And various modifications and variations are possible within the scope of the appended claims.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to be illustrative, The present invention is not limited to the drawings, but all or some of the embodiments may be selectively combined so that various modifications may be made.

100: Power storage device
B: Battery group
BMS: Battery management system
210: Current sensor
220: Voltage sensor
300: Integrated controller
CB: Circuit breaker
SL: Sub power line
ML: main power line
HL: 1st integrated power line
LL: 2nd integrated power line

Claims (8)

A plurality of battery groups arranged in mutually parallel connection and having cathodes commonly connected to a second integrated power line;
A plurality of battery management systems that individually monitor states of the plurality of battery groups;
A plurality of sub power lines interconnecting first electrodes of two adjacent battery groups among the plurality of battery groups;
A plurality of main power lines, one end of which is connected to the plurality of sub power lines on a one-to-one basis and the other end is commonly connected to a first integrated power line; And
And a plurality of breakers provided for each of the plurality of sub power lines and the connection nodes of the plurality of main power lines,
Each of the battery management systems includes:
And outputs a current cutoff signal for turning off at least two breakers among the plurality of breakers when a state of a battery group designated to itself among the plurality of battery groups is determined to be a predetermined abnormal state.
The method according to claim 1,
Each of the battery management systems includes:
And determines that the battery group assigned to the battery management system is in an abnormal state when the voltage of the battery group assigned to itself is equal to or lower than a predetermined discharge end voltage.
The method according to claim 1,
Each of the battery management systems includes:
And determines that the battery group designated in the battery management system is in an abnormal state when the SOH of the battery group designated to itself is equal to or less than a predetermined threshold SOH.
The method according to claim 1,
Each of the battery management systems includes:
And determines that the battery group assigned to the battery management system is in an abnormal state when the current of the battery group designated to itself is equal to or greater than a predetermined threshold current.
The method according to claim 1,
Further comprising: a plurality of controllers provided one-to-one on the plurality of circuit breakers,
Each of the controllers,
And turns off any one of the breakers assigned to itself when receiving the current interruption signal.
The method according to claim 1,
Each of the battery management systems includes:
When the state of a battery group designated to itself is determined to be a predetermined abnormal state, the current cutoff signal is applied to two breakers respectively provided at connection nodes of two sub power lines connected to the first electrode of a battery group designated to itself The power storage device.
The method according to claim 6,
And an integrated controller configured to be able to individually communicate with the plurality of battery management systems,
The integrated control unit,
A number of battery groups electrically connected to the first and second integrated power lines of the plurality of battery groups; And a current value of the first and second integrated power lines, and sets a target number indicating the target number to each of the plurality of battery management systems.
8. The method of claim 7,
Each of the battery management systems includes:
And transmits the current interruption signal to the circuit breaker corresponding to the target number of the plurality of circuit breakers in accordance with the setting signal when the state of any one of the battery groups designated to itself is determined to be a predetermined abnormal state.

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