KR20190086967A - Battery management system and method for diagnosing a fault of a busbar - Google Patents

Abstract

Disclosed are a battery management system for diagnosing a fault of a busbar installed between two battery modules and a method thereof. According to one embodiment of the present invention, the battery management system comprises: a voltage measurement circuit connected to the other end of each of a first sensing wire having one end connected to one end of the busbar and a second sensing wire having one end connected to the other end of the busbar and configured to measure a diagnostic voltage indicating a potential difference between the other end of the first sensing wire and the other end of the second sensing wire; and a control unit operably coupled to the voltage measurement circuit. The control unit is configured to: determine a first voltage value corresponding to a diagnostic voltage measured by the voltage measurement circuit at a first time in which a current which flows via the first battery module and the second battery module is cut off; determine a second voltage value corresponding to a diagnostic voltage measured by the voltage measurement circuit at a second time in which the current which flows via the first battery module and the second battery module exceeds a reference voltage; and determine whether the busbar has a fault based on the first voltage value and the second voltage value.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery management system and method for diagnosing a failure of a bus bar,

The present invention relates to a battery management system and method, and more particularly, to a battery management system and method for diagnosing a failure of a bus bar installed between two battery modules.

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.

In recent years, in order to provide a high voltage, a demand for a battery pack including two or more battery modules connected in series through a bus bar is increasing. One end of the bus bar is connected to the positive terminal of one of the battery modules and the other end of the bus bar is connected to the negative terminal of the other battery module so that a path of current through the two battery modules can be provided.

However, due to external impact or aging of the bus bar itself, the connection between the bus bar and the battery module may be deteriorated. For example, if cracks occur in the bus bar, or if the contact area between one end of the bus bar and the terminals of the battery module is reduced, the resistance of the current path between the two battery modules may increase and heat generation may become worse, The battery module may be electrically disconnected completely.

Thus, there is a growing need for a technique that can properly diagnose faults in bus bars that provide a current path between two battery modules.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a battery management system and method for properly diagnosing a failure of a bus bar that provides a current path between two battery modules included in a battery pack .

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 battery management system for diagnosing a failure of a bus bar connected between a first battery module and a second battery module according to an embodiment of the present invention includes a first sensing wire having one end connected to one end of the bus bar, A voltage measuring circuit connected to the other end of each of the second sensing wires connected to the other end of the bus bar and configured to measure a diagnostic voltage indicating a potential difference between the other end of the first sensing wire and the other end of the second sensing wire; And a controller operatively coupled to the voltage measurement circuit. The control unit determines a first voltage value corresponding to the diagnostic voltage measured by the voltage measurement circuit at a first time when the flow of current through the first battery module and the second battery module is blocked. The control unit determines a second voltage value corresponding to the diagnostic voltage measured by the voltage measurement circuit at a second time when a current flowing through the first battery module and the second battery module exceeds a reference current. The controller diagnoses whether the bus bar is faulty based on the first voltage value and the second voltage value.

The controller may determine the second voltage value when the first voltage value is equal to or greater than the reference voltage value.

The controller may diagnose that the bus bar is broken when the difference between the first voltage value and the second voltage value is equal to or greater than the threshold voltage value.

Wherein the controller is configured to control at least one of the first sensing wire and the second sensing wire when the first voltage value is equal to or greater than the reference voltage value and the difference between the first voltage value and the second voltage value is less than the threshold voltage value One can be diagnosed as having a failure.

The control unit may calculate the resistance of the bus bar based on the first voltage value and the second voltage value and diagnose that the bus bar is faulty when the resistance of the bus bar is equal to or greater than the threshold resistance.

The control unit calculates the following equation:

The resistance of the bus bar can be calculated. In the equation, V _{diag _1} is the first voltage value, V _{diag _ 2} are the second voltage values, I _m is the current at the second time that flows through the first battery module and second battery module, R _bus is the resistance of the bus bar.

The controller may diagnose that the first sensing wire or the second sensing wire is faulty when the first voltage value is equal to or greater than the reference voltage value and the resistance of the bus bar is less than the threshold resistance.

The control unit may generate a diagnostic message indicating a diagnostic result of the failure of the bus bar.

The battery pack according to another embodiment of the present invention includes the battery management system.

A method for diagnosing a fault in a bus bar connected between a first battery module and a second battery module according to another embodiment of the present invention is characterized in that the flow of current through the first battery module and the second battery module Determining a first voltage value corresponding to the diagnostic voltage measured at the first time off; Determining a second voltage value corresponding to a diagnostic voltage measured at a second time when a current flowing through the first battery module and the second battery module exceeds a reference current; And determining whether the bus bar is faulty based on the first voltage value and the second voltage value. The diagnostic voltage represents a potential difference between the other end of the first sensing wire, one end of which is connected to one end of the bus bar, and the other end of the second sensing wire, which is connected to the other end of the bus bar.

The step of determining whether the bus bar is faulty may diagnose that the bus bar is faulty if the difference between the first voltage value and the second voltage value is equal to or greater than a threshold voltage value.

Wherein the step of determining whether the bus bar is faulty comprises: calculating a resistance of the bus bar based on the first voltage value and the second voltage value; And diagnosing that the bus bar is faulty if the resistance of the bus bar is greater than or equal to the threshold resistance.

A recording medium according to another embodiment of the present invention records a computer program for executing the above method.

According to at least one of the embodiments of the present invention, the failure of the bus bar providing the current path between the two battery modules included in the battery pack can be suitably diagnosed.

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 functional block diagram of a battery pack according to an embodiment of the present invention.
FIG. 2 is an exemplary view illustrating a state where the first battery module shown in FIG. 1 is connected to the second battery module through a bus bar.
Fig. 3 is a diagram showing equivalently a closed circuit corresponding to area A in Fig. 1 using a resistor. Fig.
4-7 are flowcharts illustrating a method for detecting a busbar failure according to different embodiments 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" .

FIG. 1 is a diagram showing a functional configuration of a battery pack 1 according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of a first battery module 11 shown in FIG. 1, FIG. 3 is an equivalent view of a closed circuit corresponding to region A in FIG. 1, using a resistor. FIG.

1 and 2, the battery pack 1 includes a first pack terminal P +, a second pack terminal P-, a battery assembly 10, a bus bar 20, a switch 30, A first sensing wire 41, a second sensing wire 42, and a battery management system 100.

The battery assembly 10 includes a first battery module 11 and a second battery module 12. Each of the first battery module 11 and the second battery module 12 includes one or more battery cells. The first battery module 11 includes a positive electrode terminal 11a and a negative electrode terminal 11b. The second battery module 12 includes a positive terminal 12a and a negative terminal 12b.

The bus bar 20 is electrically connected between the first battery module 11 and the second battery module 12. Specifically, one end of the bus bar 20 is connected to the positive electrode terminal 11a of the first battery module 11, and the other end of the bus bar 20 is connected to the negative electrode terminal 12b of the second battery module 12. [ Can be connected. That is, the first battery module 11 and the second battery module 12 are connected in series between the first pack terminal P + and the second pack terminal P- through the bus bar 20, The bar 20 provides a current path between the first battery module 11 and the second battery module 12. A portion where one end of the bus bar 20 is connected to the positive electrode terminal 11a of the first battery module 11 is connected to the first node and the other end of the bus bar 20 and the second battery module 12 The portion to which the negative terminal 12b is connected will be referred to as a second node.

The switch 30 is provided on the high potential side or the low potential side of the battery pack 1. [ The high potential side is a large current path between the positive terminal 12a of the second battery module 12 and the first pack terminal P + May be a large current path between the terminals P-. The switch 30 is turned on or off according to the switching signal from the control unit 140 or the external device 2. [ The external device 2 may be, for example, an ECU (eletronic control unit) of an electric vehicle.

While the switch 30 is turned on, the pack current can flow through the large current path of the battery pack 1. [ On the other hand, while the switch 30 is turned off, the flow of the pack current through the high current path of the battery pack 1 is cut off. As the switch 30, for example, a semiconductor relay such as a mechanical relay or a MOSFET equipped with an electromagnet may be used.

The first sensing wire 41 is connected at one end to the first node and at the other end to the battery management system 100. The first sensing wire 41 serves to transmit the potential of the first node to the battery management system 100.

The second sensing wire 42 is connected at one end to the second node and at the other end to the battery management system 100. The second sensing wire 42 serves to transfer the potential of the second node to the battery management system 100.

The battery management system 100 includes a voltage measurement circuit 110 and a control unit 140. The battery management system 100 may further include at least one of a current sensor 120, a temperature sensor 130, and a communication unit 150.

The voltage measuring circuit 110 is implemented using application specific integrated circuits (ASICs) or the like and includes at least one voltage sensor (not shown), a first voltage sensing terminal S ₁ and a second voltage sensing terminal S ₂ ). The voltage measuring circuit 110 may further include a current source 111. The current source 111 may be connected between the first voltage sensing terminal S ₁ and the second voltage sensing terminal S ₂ . Accordingly, a closed circuit (region A in FIG. 1) including the first sensing wire 41, the bus bar 20, the second sensing wire 42 and the current source 111 can be formed in the battery pack 1 have. A constant current supplied by the current source 111 flows along the closed circuit so that a potential difference is generated between one end and the other end of each of the first sensing wire 41, the bus bar 20 and the second sensing wire 42 .

The first voltage sensing terminal S ₁ is connected to the other end of the first sensing wire 41. The second voltage sensing terminal S ₂ is connected to the other end of the second sensing wire 42. The voltage measuring circuit 110 periodically or in response to a command from the controller 140 measures the diagnostic voltage which is the voltage between the first voltage sensing terminal S ₁ and the second voltage sensing terminal S ₂ .

The diagnostic voltage indicates a potential difference between the other end of the first sensing wire 41 and the other end of the second sensing wire 42 and is a voltage V ₁ between one end and the other end of the first sensing wire 41, Corresponds to the sum of V ₂ , which is the voltage between one end and the other end of the sensing wire 42, and V _bus , which is the voltage between one end and the other end of the bus bar 20. 3, the resistance between one end of the first sensing wire 41 and the other end of the second sensing wire 42 is R ₁ , the resistance between the other end of the second sensing wire 42 is R ₂ , The resistance between the other ends is R _bus , the constant current outputted from the current source 111 is I _cst , and the pack current is I _pack , the diagnostic voltage V _diag can be expressed by the following equation (1).

&Quot; (1) "

V _diag = V ₁ + V ₂ + V _bus = R ₁ I _cst + R ₂ I _cst + R _bus (I _cst + I _pack )

R ₁ is the resistance of the first sensing wire 41, the contact resistance between one end of the first sensing wire 41 and the first node, and the contact resistance between the other end of the first sensing wire 41 and the first voltage sensing terminal S ₁ ) of the contact resistance.

R ₂ is the resistance of the second sensing wire 42, the contact resistance between one end of the second sensing wire 42 and the second node, and the contact resistance between the other end of the second sensing wire 42 and the second voltage sensing terminal S ₂ ) of the contact resistance.

The R _bus may correspond to a sum of resistivity of the bus bar 20, contact resistance between one end of the bus bar 20 and the first node, and contact resistance between the other end of the bus bar 20 and the second node.

The voltage measuring circuit 110 outputs a voltage signal indicating the measured diagnostic voltage to the control unit 140. [ Referring to Equation 1, those skilled in the art will readily understand that if the pack current I _{pack, which} is the current flowing through the first battery module 11 and the second battery module 12, changes, the diagnostic voltage V _diag will also change .

The voltage measuring circuit 110 is included in the first battery module 11 and the second battery module 12 through an additional sensing wire (not shown) other than the first sensing wire 41 and the second sensing wire 42 And may output a signal indicating the measured cell voltage to the control unit 140. The control unit 140 may be configured to measure the cell voltage of each battery cell.

The current sensor 120 measures the current flowing through the large current path of the battery pack 1. [ For example, as shown, the current sensor 120 may be installed between the positive terminal 12a of the second battery module 12 and the first pack terminal P +. Of course, the current sensor 120 may be installed between the negative terminal 11b of the first battery module 11 and the second pack terminal P-. The current sensor 120 outputs a current signal indicative of the measured current to the control unit 140.

The temperature sensor 130 may be attached to or disposed adjacent to at least one of the first battery module 11 and the second battery module 12. [ The temperature sensor 130 measures the temperature of at least one of the first battery module 11 and the second battery module 12 and outputs a temperature signal indicating the measured temperature to the controller 140.

The controller 140 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 (FPGAs) microprocessors, and other electronic units for performing other functions. The control unit 140 may include a memory. A program and various data for executing a method to be described later can be stored in the memory. The memory may be, for example, 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) Lt; / RTI > type of storage medium.

The control unit 140 is operatively coupled to the voltage measurement circuit 110. The control unit 140 may be operably coupled to the switch 30, the current sensor 120, the temperature sensor 130, and the communication unit 150.

The control unit 140 estimates the state of charge and life of each of the first battery module 11 and the second battery module 12 based on at least one of the voltage signal, the current signal, and the temperature signal, To the external device (2) through the communication unit (150).

The control unit 140 can determine whether the current flowing through the first battery module 11 and the second battery module 12 is equal to or lower than the reference current based on the current signal from the current sensor 120 .

The control unit 140 can determine the first voltage value corresponding to the diagnostic voltage measured by the voltage measurement circuit 110 at the first time. The first time may be a time within a period in which the pack current is less than the reference current or the flow of the pack current is blocked as the switch 30 is turned off. For example, the first voltage value is a diagnostic voltage measured when the pack current I _pack is 0 A, in which case the first voltage value depends only on the constant current of the current source 111. Therefore, the first voltage value can be expressed by Equation (2) below from Equation (1).

&Quot; (2) "

V _{diag _ 1} = (R ₁ + R ₂ + R _bus ) I _cst

V _{diag _1} shows a first voltage value.

Alternatively, the first voltage value may be indicative of an experimentally predetermined voltage, rather than a diagnostic voltage measured by the voltage measurement circuit 110.

The control unit 140 can determine the second voltage value corresponding to the diagnostic voltage measured by the voltage measurement circuit 110 at the second time. The second time may be a time at which a pack current different from the pack current at the first time flows. For example, the second time may be a time within a period (for example, during charging of the battery pack 1) in which the pack current exceeds the reference current (for example, 0.1 A) as the switch 30 is turned on. When the pack current I _pack measured by the current sensor 120 at the second time is equal to I _m , the second voltage value can be expressed by Equation (3) from Equation (1).

&Quot; (3) "

_{V diag _2 = (R 1 +} R 2) I cst + R bus (I cst + I _m )

_Diag V _{_ 2} shows a second voltage value.

The reference current may be predetermined according to the measurement error of the current sensor 120 or may be changeable by the control unit 140. [

The control unit 140 can diagnose the failure of the bus bar 20 based on the first voltage value and the second voltage value. For example, when the difference between the first voltage value and the second voltage value is equal to or greater than the threshold voltage value, the control unit 140 diagnoses that the bus bar 20 is malfunctioning. Otherwise, the first sensing wire 41 And the second sensing wire 42 may be diagnosed to be malfunctioning.

Alternatively, the controller 140 may calculate the resistance of the bus bar 20 based on the first voltage value and the second voltage value, and then, when the calculated resistance of the bus bar 20 is equal to or greater than the threshold resistance, It is possible to diagnose that the bar 20 is malfunctioning. The control unit 140 can calculate the resistance of the bus bar 20 using the following equation (4).

&Quot; (4) "

The control unit 140 selects a critical resistance associated with a temperature range to which the temperature signal from the temperature sensor 130 belongs and selects the selected critical resistance by using Equation 4 The failure of the bus bar 20 can be diagnosed by comparing the calculated resistance with the resistance of the bus bar 20. [ Of course, the threshold resistance may be predetermined regardless of the temperature of the first battery module 11 or the second battery module 12. [

The communication unit 150 is configured to support bidirectional communication between the control unit 140 and the external device 2. [ The communication unit 150 can transmit a diagnostic message indicating the diagnosis result from the control unit 140 to the external device 2. [ The communication unit 150 can transmit a command from the external device 2 to the control unit 140. [

4 is a flowchart showing a method for detecting a failure of the bus bar 20 according to an embodiment of the present invention.

Referring to FIG. 4, in step S400, the control unit 140 determines a first voltage value indicating the diagnostic voltage measured at the first time. The first time may be a time within a period in which the pack current is less than the reference current or the flow of the pack current is blocked. The first voltage value may be experimentally predetermined, and in this case, step S400 may be omitted.

In step S410, the control unit 140 determines a second voltage value indicating the diagnostic voltage measured at the second time. The second time may be a time within a period in which the pack current exceeds the reference current. In this case, the reference current may be predetermined.

In step S420, the control unit 140 calculates the difference between the first voltage value and the second voltage value. The difference between the first voltage value and the second voltage value may be an absolute value of a value obtained by subtracting one from the first voltage value and the second voltage value.

In step S430, the control unit 140 determines whether the difference between the first voltage value and the second voltage value is equal to or greater than the threshold voltage value. If the value of step S430 is YES, step S440 is performed. If the value of step S440 is "NO ", the process proceeds to step S450.

In step S440, the control unit 140 generates a diagnostic message indicating that the bus bar 20 has failed.

In step S450, the control unit 140 generates a diagnostic message indicating that at least one of the first sensing wire 41 and the second sensing wire 42 is faulty.

In step S460, the control unit 140 transmits the diagnostic message to the external device 2 through the communication unit 150. [

5 is a flowchart showing a method for detecting a failure of the bus bar 20 according to another embodiment of the present invention.

Referring to FIG. 5, in step S500, the control unit 140 determines a first voltage value indicating the diagnostic voltage measured at the first time. The first time may be a time within a period in which the pack current is less than the reference current or the flow of the pack current is blocked. The first voltage value may be experimentally predetermined, and in this case, step S500 may be omitted.

In step S510, the control unit 140 determines a second voltage value indicating the diagnostic voltage measured at the second time. The second time may be a time within a period in which the pack current exceeds the reference current. In this case, the reference current may be predetermined.

In step S520, the control unit 140 calculates the resistance of the bus bar 20 based on the first voltage value and the second voltage value. In this case, the controller 140 can calculate the resistance of the bus bar 20 using Equation (4).

In step S530, the control unit 140 determines whether or not the resistance of the bus bar 20 is equal to or greater than the threshold resistance. If the value of step S530 is YES, step S540 is performed. If the value of step S540 is NO, step S550 is performed.

In step S540, the control unit 140 generates a diagnostic message indicating that the bus bar 20 has failed.

In step S550, the control unit 140 generates a diagnostic message indicating that at least one of the first sensing wire 41 and the second sensing wire 42 is faulty.

In step S560, the control unit 140 transmits the diagnostic message to the external device 2 through the communication unit 150. [

6 is a flowchart showing a method for detecting a failure of the bus bar 20 according to another embodiment of the present invention.

Referring to FIG. 6, in step S600, the control unit 140 determines a first voltage value representing the diagnostic voltage measured at the first time. The first time may be a time within a period in which the pack current is less than the reference current or the flow of the pack current is blocked.

In step S605, the control unit 140 determines whether or not the first voltage value is equal to or greater than the first reference voltage value. The first reference voltage value may be a predetermined experimentally based on the constant current of the current source 111 and the intrinsic resistance of each of the first sensing wire 41, the second sensing wire 42 and the bus bar 20 . The first voltage value being equal to or higher than the first reference voltage value indicates that at least one of the first sensing wire 41, the second sensing wire 42, and the bus bar 20 has failed. On the other hand, when the first voltage value is less than the first reference voltage value, it is determined that none of the first sensing wire 41, the second sensing wire 42, and the bus bar 20 is malfunctioning . If the value of step S605 is "YES ", the process proceeds to step S610. If the value of step S605 is "NO ", the process may return to step S600.

In step S610, the control unit 140 determines a second voltage value representing the diagnostic voltage measured at the second time. The second time may be a time within a period in which the pack current exceeds the reference current. In this case, the reference current may be predetermined.

In step S620, the control unit 140 calculates a difference between the first voltage value and the second voltage value.

In step S630, the control unit 140 determines whether the difference between the first voltage value and the second voltage value is equal to or greater than the threshold voltage value. If the value of the step S630 is "YES ", the step S640 proceeds. If the value of the step S640 is "NO ", the step S650 proceeds. Instead of steps S620 and S630, steps S520 and S530 of FIG. 5 may be performed.

In step S640, the control unit 140 generates a diagnostic message indicating that the bus bar 20 has failed.

In step S650, the control unit 140 generates a diagnostic message indicating that at least one of the first sensing wire 41 and the second sensing wire 42 is faulty.

In step S660, the control unit 140 transmits the diagnostic message to the external device 2 via the communication unit 150. [

7 is a flowchart showing a method for detecting a failure of the bus bar 20 according to another embodiment of the present invention.

Referring to Fig. 7, in step S700, the control unit 140 determines a first voltage value indicating the diagnostic voltage measured at the first time. The first time may be a time within a period in which the flow of the pack current is blocked.

In step S705, the control unit 140 determines the reference current based on the difference between the first voltage value and the second reference voltage value. For example, when the first voltage value is equal to or lower than the second reference voltage value, the controller 140 determines a predetermined current (e.g., 10A) as the reference current. On the other hand, when the first voltage value is greater than the second reference voltage value A current inversely proportional to a value obtained by subtracting the second reference voltage value from the first voltage value can be determined as the reference current. The second reference voltage value may be predetermined experimentally based on the constant current of the current source 111 and the intrinsic resistance of each of the first sensing wire 41, the second sensing wire 42 and the bus bar 20 .

In step S710, the control unit 140 determines a second voltage value representing the diagnostic voltage measured at the second time. The second time may be a time within a period in which the pack current exceeds the reference current determined in step S705.

In step S720, the control unit 140 calculates the difference between the first voltage value and the second voltage value.

In step S730, the control unit 140 determines whether the difference between the first voltage value and the second voltage value is equal to or greater than the threshold voltage value. If the value of step S730 is YES, step S740 is performed. If the value of the step S740 is "NO ", the step S750 proceeds. Instead of steps S720 and S730, steps S520 and S530 of FIG. 5 may be performed.

In step S740, the control unit 140 generates a diagnostic message indicating that the bus bar 20 has failed.

In step S750, the control unit 140 generates a diagnostic message indicating that at least one of the first sensing wire 41 and the second sensing wire 42 is faulty.

In step S760, the control unit 140 transmits the diagnostic message to the external device 2 via the communication unit 150. [

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.

1: Battery pack
10: Battery assembly
11: first battery module
12: Second battery module
20: bus bar
30: Relay
41: first sensing wire
42: second sensing wire
100: Battery management system
110: Voltage measurement circuit
120: Current sensor
130: Temperature sensor
140:
150:

Claims (13)

A battery management system for diagnosing a failure of a bus bar connected between a first battery module and a second battery module,
A first sensing wire having one end connected to one end of the bus bar and a second sensing wire having one end connected to the other end of each of the second sensing wires connected to the other end of the bus bar and connected between the other end of the first sensing wire and the other end of the second sensing wire A voltage measuring circuit configured to measure a diagnostic voltage indicating a potential difference of the voltage; And
And a controller operatively coupled to the voltage measurement circuit,
Wherein,
Determining a first voltage value corresponding to a diagnostic voltage measured by the voltage measuring circuit at a first time when the flow of current through the first battery module and the second battery module is cut off,
Determines a second voltage value corresponding to a diagnostic voltage measured by the voltage measurement circuit at a second time when a current flowing through the first battery module and the second battery module exceeds a reference current,
And diagnoses whether or not the bus bar is faulty based on the first voltage value and the second voltage value.
The method according to claim 1,
Wherein,
And determines the second voltage value when the first voltage value is equal to or greater than the reference voltage value.
The method according to claim 1,
Wherein,
And diagnoses that the bus bar is faulty if the difference between the first voltage value and the second voltage value is greater than or equal to a threshold voltage value.
The method of claim 3,
Wherein,
When at least one of the first sensing wire and the second sensing wire is in a failure state when the first voltage value is equal to or greater than the reference voltage value and the difference between the first voltage value and the second voltage value is less than the threshold voltage value, Battery management system.
The method according to claim 1,
Wherein,
Calculating a resistance of the bus bar based on the first voltage value and the second voltage value,
And diagnoses that the bus bar is faulty if the resistance of the bus bar is greater than or equal to the threshold resistance.
6. The method of claim 5,
Wherein,
The following formula:

The resistance of the bus bar is calculated,
V _{diag _1} is the first voltage value, V _{diag _ 2} are the second voltage values, I _m is the current, R _bus flows through the first battery module and second battery module at the second time is the bus Battery management system, which is the resistance of the bar.
6. The method of claim 5,
Wherein,
And diagnoses that the first sensing wire or the second sensing wire is a failure if the first voltage value is greater than or equal to a reference voltage value and the resistance of the bus bar is less than the threshold resistance.
The method according to claim 1,
Wherein,
And generates a diagnostic message indicating a diagnosis result of whether or not the bus bar is faulty.
The battery management system according to any one of claims 1 to 8,
And a battery pack.
A method for diagnosing a fault in a bus bar connected between a first battery module and a second battery module,
Determining a first voltage value corresponding to a diagnostic voltage measured at a first time when the flow of current through the first battery module and the second battery module is blocked;
Determining a second voltage value corresponding to a diagnostic voltage measured at a second time when a current flowing through the first battery module and the second battery module exceeds a reference current; And
Determining whether the bus bar is faulty based on the first voltage value and the second voltage value,
Wherein the diagnostic voltage represents a potential difference between the other end of the first sensing wire, one end of which is connected to one end of the bus bar, and the other end of the second sensing wire, the end of which is connected to the other end of the bus bar.
11. The method of claim 10,
Wherein the step of determining whether the bus bar is faulty comprises:
If the difference between the first voltage value and the second voltage value is greater than or equal to the threshold voltage value, diagnoses that the bus bar is faulty.
11. The method of claim 10,
The step of diagnosing whether the bus bar is faulty comprises:
Calculating a resistance of the bus bar based on the first voltage value and the second voltage value; And
Diagnosing that the bus bar is faulty if the resistance of the bus bar is greater than or equal to a threshold resistance;
/ RTI >
A recording medium on which a computer program for executing the method according to any one of claims 10 to 12 is recorded.

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