BATTERY CONTROL DEVICE AND SHORT-CIRCUIT DETECTION METHOD THEREOF

Abstract

A battery control device includes: a first battery control unit configured to control an electrical connection between an external load and a first battery module, the first battery control unit including: a first switch connected between a positive terminal for the first battery module and the external load; a second switch connected between a negative terminal for the first battery module and the external load; and a first controller configured to control an open/closed state of the first and second switches. The first controller may be configured to detect a short-circuit between the external load and the first battery control unit, according to a voltage between both ends of the first switch detected with the first switch open and the second switch closed.

Claims

1. An abnormal cell detection method of a battery pack including a plurality of cells, the method comprising: receiving, by a battery management system controlling the battery pack, one or more first signals from at least one state detection device during a first rest period in which cell balancing of the plurality of cells is permitted, the first signals being indicative of a cell voltage of each of the plurality of cells; obtaining, by the battery management system, a first discharge rate of each of the plurality of cells based on cell voltage over time during the first rest period; prohibiting, by the battery management system, cell balancing of the plurality of cells if at least one cell having the first discharge rate greater than or equal to a first threshold value is detected; receiving, by the battery management system, one or more second signals from the at least one state detection device during a second rest period in which cell balancing of the plurality of cells is prohibited, the second signals being indicative of a cell voltage of each of the plurality of cells; obtaining, by the battery management system, a second discharge rate for at least one cell having the first discharge rate greater than or equal to the first threshold value among the plurality of cells, based on cell voltage over time during the second rest period; detecting, by the battery management system, an abnormal cell having the second discharge rate greater than or equal to a second threshold value; and blocking, by the battery management system, charging and discharging of the battery pack if the abnormal cell is detected.

2. The abnormal cell detection method as claimed in claim 1, wherein the second threshold value is greater than the first threshold value.

3. The abnormal cell detection method as claimed in claim 1, wherein prohibiting cell balancing includes deactivating a cell balancing function so that cell balancing is not performed even if a cell balancing initiation criterion is satisfied.

4. The abnormal cell detection method as claimed in claim 1, further comprising transferring notification information indicating that the abnormal cell is detected along with information on the abnormal cell to a user.

5. An abnormal cell detection device, comprising: a voltage detector to detect a cell voltage of each of a plurality of cells included in a battery pack; and a battery management system including at least one processor configured to: receive one or more first signals from the voltage detector during a first rest period in which cell balancing of the plurality of cells is permitted, the first signals being indicative of the cell voltage of each of the plurality of cells; obtain a first discharge rate of each of the plurality of cells based on cell voltage over time during the first rest period; prohibit cell balancing of the plurality of cells if at least one cell having the first discharge rate greater than or equal to a first threshold value is detected; receive one or more second signals from the voltage detector during a second rest period in which cell balancing of the plurality of cells is prohibited, the second signals being indicative of the cell voltage of each of the plurality of cells; obtain a second discharge rate for at least one cell having the first discharge rate greater than or equal to the first threshold value among the plurality of cells, based on cell voltage over time during the second rest period; detect an abnormal cell having the second discharge rate greater than or equal to a second threshold value; and block charging and discharging of the battery pack if the abnormal cell is detected.

6. The abnormal cell detection device as claimed in claim 5, wherein the second threshold value is greater than the first threshold value.

7. The abnormal cell detection device as claimed in claim 5, wherein the at least one processor is further configured to deactivate a cell balancing function so that cell balancing of the plurality of cells is prohibited even if a cell balancing initiation criterion is satisfied.

8. The abnormal cell detection device as claimed in claim 5, wherein the at least one processor is further configured to transfer notification information indicating that the abnormal cell is detected along with information on the abnormal cell to a user.

9. A battery pack including an abnormal cell detection device, the battery pack comprising: a voltage detector to detect a cell voltage of each of a plurality of cells included in the battery pack; and a battery management system including at least one processor, wherein the at least one processor is configured to: receive one or more first signals from the voltage detector during a first rest period in which cell balancing of the plurality of cells is permitted, the first signals being indicative of the cell voltage of each of the plurality of cells; obtain a first discharge rate of each of the plurality of cells based on cell voltage over time during the first rest period; prohibit cell balancing of the plurality of cells if at least one cell having the first discharge rate greater than or equal to a first threshold value is detected; receive one or more second signals from the voltage detector during a second rest period in which cell balancing of the plurality of cells is prohibited, the second signals being indicative of the cell voltage of each of the plurality of cells; obtain a second discharge rate for at least one cell having the first discharge rate greater than or equal to the first threshold value among the plurality of cells, based on cell voltage over time during the second rest period; detect an abnormal cell having the second discharge rate greater than or equal to a second threshold value; and block charging and discharging of the battery pack if the abnormal cell is detected.

10. The battery pack as claimed in claim 9, wherein the second threshold value is greater than the first threshold value.

11. The battery pack as claimed in claim 9, wherein the at least one processor is further configured to deactivate a cell balancing function so that cell balancing of the plurality of cells is prohibited even if a cell balancing initiation criterion is satisfied.

12. The battery pack as claimed in claim 9, wherein the at least one processor is further configured to transfer notification information indicating that the abnormal cell is detected along with information on the abnormal cell to a user.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Features will become apparent to those of skill in the art by describing in detail example embodiments with reference to the attached drawings in which:

[0026] FIG. 1 schematically illustrates a battery system according to an example embodiment.

[0027] FIG. 2A and FIG. 2B illustrate cases in which a short-circuit accident occurs in the battery system of FIG. 1 as an example.

[0028] FIG. 3 schematically illustrates a short-circuit detection method of a battery system according to an example embodiment.

[0029] FIG. 4 schematically illustrates a battery system according to another example embodiment.

[0030] FIG. 5A and FIG. 5B illustrate cases in which a short-circuit accident occurs due to a misconnection in the battery system of FIG. 4 as an example.

[0031] FIG. 6A and FIG. 6B schematically illustrate a short-circuit detection method of a battery system according to another example embodiment.

DETAILED DESCRIPTION

[0032] Example embodiments will now be described more fully hereinafter with reference to the accompanying drawings; however, they may be embodied in different forms and should not be construed as limited to the example embodiments set forth herein. Rather, these example embodiments are provided so that this disclosure will be thorough and complete, and will fully convey exemplary implementations to those skilled in the art. In the drawing figures, the dimensions of layers and regions may be exaggerated for clarity of illustration. Like reference numerals refer to like elements throughout.

[0033] In the present specification, the term and/or includes all or random combinations of a plurality of items that are related and arranged. Regarding the description on an example embodiment, a singular term may include a plural form unless stated in another way.

[0034] Terms including ordinal numbers such as first, second, and the like will be used only to describe various components, and are not to be interpreted as limiting these components. The terms are only used to differentiate one component from other components. For example, a first constituent element could be termed a second constituent element, and similarly, a second constituent element could be termed a first constituent element, without departing from the scope.

[0035] Electrically connecting two constituent elements includes directly connecting two constituent elements and connecting the same with another constituent element therebetween. The other constituent element may include a switch, a resistor, and a capacitor. When the example embodiments are described, an expression of connection signifies electrical connection when an expression of direct connection is not provided.

[0036] FIG. 1 schematically illustrates a battery system according to an example embodiment.

[0037] Referring to FIG. 1, a battery system 10 according to an example embodiment may include a battery module 11 and a battery control device 12.

[0038] The battery module 11 may include a plurality of battery cells 111 electrically connected to each other in series or in parallel.

[0039] The battery control device 12 may detect state information such as a voltage, a current, and a temperature of the battery module 11, and may control a connection between the battery module 11 and an external device (e.g., a load 20, or a charging device (not shown)) based on the state information. The battery control device 12 may include a plurality of switches, e.g., a first switch SW11 and a second switch SW12, and a controller 121.

[0040] The first and second switches SW11 and SW12 may be respectively connected between positive and negative system terminals P+ and P (which are electrically connected to the load 20 or the charging device), and between positive and negative terminals B+ and B for respective positive and negative poles of the battery module 11 to electrically connect the battery module 11 and the positive and negative system terminals P+ and P or to block an electrical connection between them. For example, the first switch SW11 may be electrically connected between the positive terminal B+ for the battery module 11 and the negative system terminal P+, and the second switch SW12 may be connected between the negative terminal B for the battery module 11 and the negative system terminal P. The first and second switches SW11 and SW12 may be relays, contactors, field effect switches (FET's), solid state switch (SSS's), or the like.

[0041] In order to monitor a state of the battery module 11, the controller 121 may acquire state information such as a voltage, a current, and a temperature related to the state of the battery module 11. In addition, the controller 121 may detect an overcharge or over-discharge state of the battery module 11 based on the state information of the battery module 11, and may control an open/closed state (or conductivity) of the first and second switches SW11 and SW12 based on the detected overcharge or over-discharge result. In addition, a function of detecting a short-circuit between the controller 121 and the positive and negative system terminals P+ and P may be performed.

[0042] For example, a short-circuit condition to be detected by the controller 121 may be due to an abnormal short-circuit accident. The controller 121 may detect voltages V11 and V12 at respective ends of the first switch SW11 when the second switch SW12 is in a closed state (i.e., conductive state) and the first switch SW11 is in an open state (i.e., non-conductive state), and when the voltage between respective ends of the first switch SW11 calculated therefrom (e.g., |V11V12|) is greater than 0 V (while the first switch SW11 is open and the second switch SW12 is closed), the controller 121 may determine that a short-circuit has occurred between the positive and negative system terminals P+ and P. This will now be explained in further detail.

[0043] FIG. 2A and FIG. 2B illustrate two different example cases in which a short-circuit occurs outside the battery system 10 between the positive and negative system terminals P+ and P (while the first switch SW11 is open and the second switch SW12 is closed). FIG. 2A illustrates a first case in which the positive and negative system terminals P+ and P are short-circuited with each other due to a misconnection between the positive and negative system terminals P+ and P and the load 20 resulting in the presence of a short-circuit between the positive and negative system terminals P+ and P. FIG. 2B illustrates an example in which the positive and negative system terminals P+ and P are short-circuited with each other due to a short-circuit inside the load 20.

[0044] Referring to FIG. 2A and FIG. 2B, when the first switch SW11 is open and the second switch SW12 is closed while the positive and negative system terminals P+ and P are shorted to each other, the positive system terminal P+ is electrically connected to the negative terminal B for the battery module 11 (via the short-circuit and the closed second switch SW12). Accordingly, one end of the first switch SW11 is connected to the positive terminal B+ for the battery module 11, and the other end of the (open) switch SW11 (i.e., the end at fuse F11, discussed below) is connected to the negative terminal B for the battery module 11 (via the short-circuit and the closed second switch SW12). Thus, the voltage between both ends of the switch SW11 may be about equal to an output voltage of the battery module 11 (i.e., the voltage across the battery module terminals B+, B), and thus greater than 0 V.

[0045] On the other hand, in a normal state when the positive and negative system terminals P+ and P are not shorted to each other (as in FIG. 1) and the first switch SW11 is open and the switch second SW12 is closed, the positive system terminal P+ may be in a floating state, whereby one end of the first switch SW11 is connected to the positive terminal B+ for the battery module 11 and the other end of the first switch SW11 (i.e., the end at fuse F11, discussed below) is in a floating state. In this state, a voltage measuring circuit (not shown) inside the controller 121 may detect that the voltage between both ends of the switch SW11 is 0 V or about 0 V, or may determine that the voltage between both ends of the switch SW11 is in an unmeasurable state. Accordingly, in the state in which the second switch SW12 is closed in order to detect a short-circuit, when the voltage between both ends of the first switch SW11 (in the open state) is detected as 0 V or is detected as unmeasurable, the controller 121 may determine that the system is in a normal state in which a short-circuit between the positive and negative system terminals P+ and P does not occur.

[0046] The controller 121 may perform the above-described short-circuit state detection function before an operation, e.g., before an initial operation, of the battery system 10, and when a short-circuit is detected through this, the controller 121 may control the first and second switches SW11 and SW12 to be in an open state, and may output a failure alarm or transmit a state signal warning of a short-circuit to an upper or higher-level system (not shown). On the other hand, when no short-circuit state is detected, the controller 121 may determine that a normal operation of the battery system 10 exists, and may allow for or control the switches SW11 and SW12 to be closed.

[0047] The battery control device 12 may further include at least one fuse to protect the battery module 11 from an overcurrent. Referring to FIG. 1 as an example, the battery control device 12 may further include the fuse F11 connected between the positive terminal B+ for the battery module 11 and the positive system terminal P+, and a fuse F12 connected between the negative terminal B for the battery module 11 and the negative system terminal P.

[0048] FIG. 3 schematically illustrates a short-circuit detection method of a battery system according to an example embodiment. The method of FIG. 3 may be performed by the battery control device 12 of the battery system 10 described with reference to FIG. 1.

[0049] Referring to FIG. 3, the battery control device 12, before operating the battery system 10, controls the first switch SW1 to be in the closed state through the controller 121 to detect a short-circuit condition of the positive and negative system terminals P+ and P, that is, a short-circuit condition outside the battery system 10 (S30). The first and second switches SW11 and SW12 may be in an open state before starting of the battery system 10, and when the second switch SW12 is closed, the first switch SW11 maintains an open state. In this state, the controller 121 of the battery control device 12 detects the voltage between both ends of the first switch SW11 in the open state (S31).

[0050] When the voltage between both ends of the first switch SW11 detected through operation S31 is greater than 0 V (S32), the controller 121 determines that a short-circuit occurs outside of the battery system 10, that is, that the positive and negative system terminals P+ and P are shorted to each other to form a closed circuit (S33)

[0051] As the short-circuit condition is detected, the controller 121 controls both of the first and second switches SW11 and SW12 to be in the open state (S34). In addition, the controller 121 may output a failure alarm or transmit a state signal warning that a short-circuit has occurred to the upper system.

[0052] Meanwhile, when the voltage between both ends of the first switch SW11 in operation S32 is not greater than 0 V, that is, when it is 0 V or an unmeasurable state, the controller 121 determines that a short-circuit does not occur between the positive and negative system terminals P+ and P of the battery system 10 (S35). When it is determined that the short-circuit has not occurred, the controller 121 determines that the normal operation of the battery system 10 is possible and allows the connection between the battery system 10 and the load 20 (S36). Thus, the first and second switches SW11 and SW12 are allowed to be switched to be in the closed state.

[0053] In the above-described example embodiment, the battery system 10 including one battery module 11 is illustrated as an example, but the battery system 10 may include a plurality of battery modules.

[0054] FIG. 4 schematically illustrates a battery system according to another example embodiment, wherein the battery system includes a plurality of battery modules that are connected to each other in parallel.

[0055] In FIG. 4, a battery system 40 may correspond to an energy storage system (ESS), and a load 50 connected to the battery system 40 may correspond to a power conditioning system (PCS). The load 50, e.g., a power conditioning system (PCS) may be a system that converts DC power supplied from the battery system 40, e.g., an energy storage system (ESS), into AC power to supply it to power consumers, and it may include a plurality of switches SW51 and SW52, a smoothing capacitor C, and an insulating gate bipolar transistor IGBT.

[0056] Referring to FIG. 4, the battery system 40 according to the present example embodiment may include a plurality of battery modules 41, and a battery control device for controlling connection between the plurality of battery modules 41 and the load 50. The battery control device may include a plurality of battery control units 42 respectively connected to the plurality of battery modules 41 to control connection for each battery module 41, a main controller 43, and a connecting device 44 connected between the plurality of battery control units 42 and the load 50 to control connection between the battery system 40 and the load 50.

[0057] Each battery module 41 may include a plurality of battery cells 411 electrically connected to each other in series or in parallel.

[0058] Each battery control unit 42 may detect state information such as a voltage, a current, and a temperature of the corresponding battery module 41, and may control the connection between the corresponding battery module 41 and the connecting device 44 based on this. Each battery control unit 42 may include a plurality of switches, e.g., first and second switches SW41 and SW42, and a controller 421.

[0059] The first and second switches SW41 and SW12 may be respectively connected between the positive and negative system terminals P+ and P and between both terminals of the corresponding battery module 41 to electrically connect the corresponding battery module 41 and the positive and negative system terminals P+ and P or to block an electrical connection between them. For example, the first switch SW41 may be electrically connected between a positive terminal B+ for the corresponding battery module 41 and the positive system terminal P+, and the second switch SW42 may be connected between a negative terminal B for the corresponding battery module 41 and the negative system terminal P. The first and second switches SW41 and SW42 may be relays, contactors, FETs, SSSs, or the like.

[0060] In order to monitor a state of the battery module 41, the controller 421 may acquire state information such as a voltage, a current, and a temperature related to the state of the battery module 41. In addition, the controller 421 may detect an overcharge or over-discharge state of the battery module 41 based on the state information of the battery module 41, and may control an open/closed state of the first and second switches SW41 and SW42 based on the detected overcharge or over-discharge result.

[0061] Each battery control unit 42 may further include at least one fuse to protect the corresponding battery module 41 from an overcurrent. Referring to FIG. 4 as an example, each battery control unit 42 may further include a fuse F41 connected between the positive terminal B+ for the corresponding battery module 41 and the positive system terminal P+, and a fuse F42 connected between the negative terminal B for the corresponding battery module 41 and the negative system terminal P.

[0062] The connecting device 44 may be disposed between the plurality of battery control units 42 and the load 50 to block or allow the connection between the plurality of battery control units 42 and the load 50. The connecting device 44 may include a plurality of input terminals PI and NI, a plurality of output terminals PO and NO, and a plurality of main switches, e.g., a first main switch MSW41 and a second main switch MSW42, connected between the plurality of input terminals PI and NI and the plurality of output terminals PO and NO.

[0063] The positive system terminals P+ of the battery control units 42 may be electrically connected to the positive input terminal PI, and the negative system terminals P of the battery control units 42 may be electrically connected to the negative input terminal NI. The positive output terminal PO of the connecting device 44 may be electrically connected to a positive connector T+ of the load 50, and the negative output terminal NO of the connecting device 44 may be electrically connected to a negative connector T of the load 50. The connecting device 44 may be implemented as a connecting device for configuring an electrical connection between equipments (the battery control unit 42 and the load 50) with a homopolar multi-line, and wires connected to respective input terminals PI and NI and respective output terminals PO and NO may be electrically combined to each other by a corresponding connector. Accordingly, the plurality of battery modules 41 may be connected in parallel to each other by the connecting device 44.

[0064] The first main switch MSW41 may be connected between the positive input terminal PI and the positive output terminal PO to electrically connect the positive input terminal PI and the positive output terminal PO or to block the connection between them. The second main switch MSW42 may be connected between the negative input terminal NI and the negative output terminal NO to electrically connect the negative input terminal NI and the negative output terminal NO or to block the connection between them. Opening/closing (or conductivity) of the first and second main switches MSW41 and MSW42 may be controlled by a control signal input from the main controller 43.

[0065] The main controller 43 may control the open/closed state of first and second main switches MSW41 and MSW42 included in the connecting device 44 to control the connection between the battery control units 42 and the load 50. Thus, the main controller 43 may control the supply of power from the battery system 40 to the load 50 by controlling the connection between the battery system 40 and the load 50 by controlling the open/closed state of the first and second main switches MSW41 and MSW42.

[0066] The main controller 43 may detect an actual open/closed state of the first and second main switches MSW41 and MSW42. The main controller 43 may compare the control signals output by the main controller 43 to the first and second main switches MSW41 and MSW42 with the actual open/closed states of the first and second main switches MSW41 and MSW42 to detect whether the main switches MSW41 and MSW42 are in a failure state. Thus, when the open/closed state indicated by the control signal output to the first and second main switches MSW41 and MSW42 is different from the actual open/closed state of the first and second main switches MSW41 and MSW42, the main controller 43 may determine that the first and second main switches MSW41 and MSW42 are in a failure state.

[0067] The main controller 43 may communicate with the controller 421 of each battery control unit 42. The main controller 43 may receive the state information of the corresponding battery module 41 or the open/closed state information of the corresponding first and second switches SW41 and SW42 from the controller 421 of each battery control unit 42 through communication. In addition, the main controller 43 may transmit the open/closed state information of the main switches MSW41 and MSW42 to the controller 421 of each battery control unit 42.

[0068] Each of the battery control units 42 may perform a function of detecting a short-circuit state between the positive and negative system terminals P+ and P due to misconnection or the like in a similar manner to the battery control device 12 of FIG. 1. The short-circuit state detected by the battery control unit 42 is due to an abnormal short-circuit accident. When the switch second SW12 is in the closed state (or conducting state) and the first switch SW41 is in the open state (or non-conducting state), voltages V41 and V42 at both ends of the first switch SW41 are detected, and when the detected voltages V41 and V42 at both ends of the switch SW41 are greater than 0 V, the controller 421 may determine that a short-circuit has occurred between the positive and negative system terminals P+ and P.

[0069] FIG. 5A and FIG. 5B illustrate example cases in which a short-circuit occurs between the positive and negative system terminals P+ and P due to misconnection in the battery system 40 of FIG. 4. FIG. 5A illustrates a case in which the positive and negative system terminals P+ and P are short-circuited to each other due to misconnection at the level of the battery control unit 42, that is, misconnection between the battery control unit 42 and the connecting device 44. FIG. 5B illustrates a case in which the positive and negative system terminals P+ and P are short-circuited to each other due to misconnection at the level of the battery system 40, that is, misconnection between the connecting device 44 and the load 50.

[0070] In the example illustrated in FIG. 5A, a wire NL41 between a negative system terminal P of a first battery control unit 42-1 and the connecting device 44 is misconnected, such that the positive and negative system terminals P+ and P of the first battery control unit 42-1 are both connected to the positive input terminal PI of the connecting device 44. Accordingly, the positive and negative system terminals P+ and P of the first battery control unit 42-1 are shorted to each other when the first and second switches SW41 and SW42 of the first battery control unit 42-1 are closed, a short-circuit current Ishort occurs.

[0071] In the example illustrated in FIG. 5B, a wire PL42 connected to the positive output terminal PO of the connecting device 44 is misconnected to the negative connector T instead of the positive connector T+ of the load 50, and a wire NL42 connected to the negative output terminal NO is misconnected to the positive connector T+ of the load 50. Accordingly, the output terminals PO and NO of the connecting device 44 are short-circuited to each other when the first and second switches SW41 and SW42 of a battery control unit 42 are closed and the first and second main switches MSW41 and MSW42 are closed, and the short-circuit current Ishort occurs.

[0072] As shown in FIG. 5A, when a short-circuit occurs between the first battery control unit 42-1 and the connecting device 44 due to misconnection and the like, the first battery control unit 42-1 may detect the occurrence of the short-circuit by performing the above-described short-circuit detection function, regardless of the open/closed state of the main switches MSW41 and MSW42. Thus, the controller 421 of the first battery control unit 42-1 may measure the voltages V41 and V42 at both ends of the first switch SW41 in the open state (with the second switch SW12 in the closed state), thereby detecting occurrence of a short-circuit between the positive and negative system terminals P+ and P of the first battery control unit 42-1.

[0073] As shown in FIG. 5B, when a short-circuit occurs between the connecting device 44 and the load 50 due to misconnection, any of the battery control units 42 may detect the occurrence of the short-circuit by performing the above-described short-circuit detection function when both of the first and second main switches MSW41 and MSW42 of the connecting device 44 are closed. Thus, the controller 421 of one of the battery control units 42, e.g., the first battery control unit 42-1, may control its second switch SW42 to be in the closed state while the first and second main switches MSW41 and MSW42 are both closed, and in this state, it may detect a short-circuit between its positive and negative system terminals P+ and P by measuring the voltages V41 and V42 at both ends of its first switch SW41 while its first switch SW41 is in the open state.

[0074] Based on the above, a short-circuit occurs between the battery control units 42 and the connecting device 44 or between the connecting device 44 and the load 50, may be detected. For example, the battery system 40 may first sequentially perform the short-circuit state detection function for each battery control unit 42 while both of the first and second main switches MSW41 and MSW42 are in the open state, to thus check the connection state, that is, the short-circuit occurrence, between each of the battery control units 42 and the connecting device 44. Then, after confirming that all the connection states between the battery control units 42 and the connecting device 44 are all normal, both the main switches MSW41 and MSW42 may be closed, and in this state, the connection state between the connecting device 44 and the load 50 may be checked by performing the above-described short-circuit detection function in one of the battery control units 42.

[0075] The battery control units 42 may perform the above-described short-circuit state detection function before an operation, e.g., an initial operation, of the battery system 40, and when a short-circuit is detected through this, they may control the corresponding first and second switches SW41 and SW42 to be in an open state, and may transmit a state signal warning of this to the main controller 43. On the other hand, when no short-circuit state is detected by any of the battery control units 42, the battery control units 42 determine that a normal operation of the battery system 40 is possible and allow the corresponding switches SW41 and SW42 to be closed. In addition, a state signal notifying a normal state of the connections between the battery control units 42 and the connecting device 44, and the connection between the connecting device 44 and the load 50, may be transmitted to the main controller 43.

[0076] When the main controller 43 receives a state signal indicating the occurrence of a short-circuit from at least one battery control unit 42, the main controller 43 may separate the battery system 40 from the load 50 by controlling the first and second main switches MSW41 and MSW42 to be in an open state. In addition, the main controller 43 may output a failure alarm or notify the failure occurrence to a higher-level system (not shown) or an administrator terminal (not shown). On the other hand, when the state signals indicating that the states of the connections between all the battery control units 42 and the connecting device 44, and of the connection between the connecting device 44 and the load 50, are normal are received, the main controller 43 may determine that the normal operation of the battery system 40 is possible and allows closing of the first and second main switches MSW41 and MSW42.

[0077] FIG. 6A and FIG. 6B schematically illustrate a short-circuit detection method of a battery system according to an example embodiment. The method of FIG. 6A and FIG. 6B may be performed by the battery control device of the battery system 40 described with reference to FIG. 4.

[0078] Referring to FIG. 6A, in order to detect a short-circuit in a level of the battery control unit 42 before an operation of the battery system 40, the battery control device maintains the first and second main switches MSW41 and MSW42 in an open state (S60), and in this state, it sequentially performs short-circuit detection for each battery control unit 42 (S61).

[0079] FIG. 6B specifically illustrates a method of performing the short-circuit detection at the level of the battery control unit 42 in each battery control unit 42 in operation S61.

[0080] Referring to FIG. 6B, the controller 421 of each battery control unit 42 controls the second switch SW42 to be in a closed state through the controller 421 in order to detect occurrence of a short-circuit between the battery control unit 42 and the connecting device 44 (S610). In this case, the first switch SW41 of the corresponding battery control unit 42 maintains an open state, and the controller 421 detects a voltage between both ends of the first switch SW41 of the open state (S611).

[0081] When the voltage between both ends of the first switch SW41 detected through operation S611 is greater than 0 V (S612), the controller 421 determines that a short-circuit occurs between the corresponding battery control unit 42 and the connecting device 44 to form a closed circuit, e.g., the controller determines that the positive and negative system terminals P+ and P have been shorted to each other (S613). As the short-circuit is detected, the controller 421 may transmit a state signal, indicating that the short-circuit has occurred between the corresponding battery control unit 42 and the connecting device 44, to the main controller 43.

[0082] Meanwhile, when the voltage between both ends of the first switch SW41 in operation S612 is not greater than 0 V, that is, when it is 0 V or an unmeasurable state, the controller 421 determines that no short-circuit occurs between the corresponding battery control unit 42 and the connecting device 44 (S614). When it is determined that no short-circuit occurs, the controller 421 may transmit a state signal, indicating that the connection between the corresponding battery control unit 42 and the connecting device 44 is in a normal state, to the main controller 43.

[0083] Each battery control unit 42 may detect occurrence of a short-circuit between the corresponding battery control unit 42 and the connecting device 44 by performing operation S610 to operation S613 described above. On the other hand, while one battery control unit 42 detects the short-circuit through operation S601 to operation S613 described above, the remaining battery control units 42 remain disconnected from the connecting device 44 in order to not affect the detection result (that is, the switches SW41 and SW42 are open).

[0084] Referring back to FIG. 6A, when no short-circuits between the battery control units 42 and the connecting device 44 are detected in operation S61 described above (S62), the main controller 43 then controls the first and second main switches MSW41 and MSW42 to be in a closed state (S63) in order to detect the occurrence of a short-circuit in the battery system 40, that is, the occurrence of a short-circuit between the connecting device 44 and the load 50. Thus, control signals instructing switching to a closed state may be output to the first and second main switches MSW41 and MSW42.

[0085] In this state, the main controller 43 obtains an actual open/closed state of the first and second main switches MSW41 and MSW42 from the connecting device 44 (S64), and based on this, it first determines whether the first and second main switches MSW41 and MSW42 are in a failure state. Thus, in the state in which the control signals instructing the switching of the closed state are output to the first and second main switches MSW41 and MSW42, when the detected actual open/closed state of the first and second main switches MSW41 and MSW42 indicates that the first main switch MSW41 or the second main switch MSW42 is in an open state (S65), the main controller 43 detects that the main switch MSW41 or the main switch MSW42 is in a failure state (S66). On the other hand, when both the first and second main switches MSW41 and MSW42 are in the closed state (S65), it is determined that both the first and second main switches MSW41 and MSW42 are normally operating, i.e., are each in a normal state, and a process of detecting the short-circuit between the connecting device 44 and the load 50 is performed.

[0086] Thus, the main controller 43 instructs the controller 421 of one of the battery control units 42 (for example, the first battery control unit 42-1 of FIG. 5B) to detect a short-circuit, and the controller 421 receiving this controls the corresponding second switch SW42 to be in a closed state (S67). In this case, the first switch SW41 of the corresponding battery control unit 42-1 maintains an open state, and the controller 421 detects a voltage between both ends of the first switch SW41 while the first switch SW41 is in the open state (S68).

[0087] When the voltage between both ends of the first switch SW41 detected through operation S68 is greater than 0 V (S69), the controller 421 determines that a short-circuit occurs between the corresponding connecting device 44 and the load 50 to form a closed circuit, e.g., the controller 421 determines that the positive and negative system terminals P+ and P are shorted to each other (S70). Meanwhile, when the voltage between both ends of the switch SW41 in operation S69 is not greater than 0 V, that is, when it is 0 V or an unmeasurable state, the controller 421 determines that a short-circuit does not occur between the connecting device 44 and the load 50 (S72).

[0088] When the short-circuit is detected between the at least one battery control unit 42 and the connecting device 44 through the above-described operation S62, when the failure of at least one of the main switches MSW41 and MSW42 is detected in the above-described operation S65, or when the short-circuit between the connecting device 44 and the load 50 is detected through the above-described operation S69, the main controller 43 may instruct each controller 421 to release the connection between each battery control unit 42 and the connecting device 44, that is, to open the switches first and second SW41 and SW42, and may block the connection between the battery system 40 and the load 50 by opening the first and second main switches MSW41 and MSW42 (S71).

[0089] On the other hand, when no short-circuit is detected and failure of the main switches MSW41 and MSW42 is not detected, the main controller 43 instructs each controller 421 to allow the closed state of the first and second switches SW41 and SW42, and allows the connection between the battery system 40 and the load by allowing the closed state of the first and second main switches MSW41 and MSW42 (S73).

[0090] According to the above-described example embodiments, before the battery systems 10 and 40 are operated as the power source of the loads 20 and 50, the short-circuit state caused by misconnection inside or outside the battery systems 10 and 40 may be detected. Therefore, it may be possible to detect the short-circuit state and take appropriate measures before the components of the battery systems 10 and 40 are damaged due to the short-circuit current, thereby preventing the damage of the components and consequent replacement costs, and increasing the lifespan of the battery systems 10 and 40. In addition, such a short-circuit detection procedure may be automatically performed by the battery systems 10 and 40, so that human error, e.g., due to inexperience of the administrator, may be avoided, and the detection time may be shortened, thereby further improving safety and efficiency of the system.

[0091] Electronic or electrical devices according to example embodiments and/or other related devices or constituent elements may be realized by using appropriate hardware, firmware (e.g., an application-specific integrated circuit), software, or combinations of software, firmware, and hardware. For example, various configurations of the above-noted devices may be positioned on one integrated circuit (IC) chip or an individual IC chip. In addition, various configurations of the above-noted devices may be realized on a flexible printed circuit film, a tape carrier package (TCP), a printed circuit board (PCB), or one substrate. The electrical or mutual connections described in the present specification may, for example, be realized by the PCB, wires on different types of circuit carriers, or conductive elements. The conductive elements may, for example, include metallization such as surface metallizations and/or pins, and may include conductive polymers or ceramics.

[0092] In addition, the various configurations of the devices may be implemented by at least one processor so as to perform the above-described various functions, they may be performed in at least one computing device, and they may be processes or threads for performing computer program instructions and interacting with other system constituent elements. The computer program instruction may be stored in a memory realizable in a computing device using a standard memory device such as a random access memory (RAM). The computer program instruction may also be stored in a non-transitory computer readable medium such as a CD-ROM or a flash drive.

[0093] By way of summation and review, if a cable of a power conditioning system is misconnected due to a human error during an ESS installation, various protective functions are desirable to prevent accidents such as electric shock, short-circuit, and fire. A representative protective function may include a misconnection monitoring function. Generally, a misconnection monitoring function may be performed in the following two methods.

[0094] A first method is a method in which, after installation of a facility is completed, a manager checks a resistance value of the installed cables with a resistance measuring instrument to check whether a short-circuit is formed, and then if the short-circuit is confirmed, it is determined that misconnection has occurred, and the facility is reconstructed. In this case, there is a possibility that a human error may occur in the process of the manager checking whether there is the misconnection with the resistance measuring instrument.

[0095] A second method is a method in which a fuse is installed inside a control box to protect a battery from a short-circuit accident caused by misconnection of a cable, and when a short-circuit accident occurs due to a short-circuit formation during a system operation, the fuse blocks a short-circuit current to protect the system. In this case, various problems may result from the short-circuit when the system is operated. For example, when a fuse blows, time and money may be expended to find the cause of blowing the fuse. The fuse may blow due to various accidents that cause short-circuit currents. However, the fuse itself has only a function of blocking the short-circuit current, and thus does not provide any function for checking the cause of the short-circuit current. The checking of the cause of the short-circuit current to eliminate the failure is performed in a way in which an operator directly checks all possible conditions for the short-circuit current to occur. As another example, since occurrence of the short-circuit current is detected while the system is in operation, when blowing of the fuse is delayed in a short-circuit condition, the system may be exposed to a high short-circuit current for some time, and thus accidents such as component damage, explosion, and insulation breakdown may occur. As another example, in order to identify the cause of a blown fuse and restart the system, recovery costs, such as a cost of replacement of materials to replace the blown fuse, may be incurred.

[0096] As described above, embodiments may provide a battery control device and a short-circuit detection method thereof that may accurately detect whether a short-circuit occurs, due to misconnection or the like, prior to an operation of a battery system.

[0097] Example embodiments have been disclosed herein, and although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purpose of limitation. In some instances, as would be apparent to one of ordinary skill in the art as of the filing of the present application, features, characteristics, and/or elements described in connection with a particular embodiment may be used singly or in combination with features, characteristics, and/or elements described in connection with other embodiments unless otherwise specifically indicated. Accordingly, it will be understood by those of skill in the art that various changes in form and details may be made without departing from the spirit and scope of the present invention as set forth in the following claims.

DESCRIPTION OF SYMBOLS

[0098] 10, 40: battery systems [0099] 11, 41: battery modules [0100] 111, 411: battery cells [0101] 12: battery control device [0102] 121: controller [0103] 20, 50: loads [0104] 42, 42-1: battery control units [0105] 421: controller [0106] 43: main controller [0107] 44: connecting device [0108] F11, F12, F41, F42: fuses [0109] SW11, SW12, SW41, SW42: switches [0110] MSW41, MSW42: main switches [0111] B+, B: battery module terminals [0112] P+, P: system terminals [0113] PI, NI: input terminals of connecting device [0114] PO, NO: output terminals of connecting device