KR101749731B1 - Two-way checking device and method of bus bar locking - Google Patents

Abstract

The present invention relates to an apparatus and method for checking the state of fastening of a bus bar when a battery is charged and a method and an apparatus for checking the fastened state of a bus bar when discharging a battery, You can check the status.
Further, by using one integrated apparatus and method which use different apparatuses and methods when charging and discharging the battery, the structure is simplified and the production cost of the battery pack can be reduced.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-

The present invention relates to an apparatus and a method for confirming the fastening state of a bus bar by measuring the voltage of the bus bar in both directions regardless of the charging or discharging state of the battery.

In recent years, interest in the environment has increased, and electric batteries are attracting attention as electric power sources for electric vehicles and hybrid vehicles, which are proposed as solutions for air pollution caused by existing gasoline vehicles and diesel vehicles using fossil fuels have.

Such electric vehicles or hybrid vehicles are required to have a high-power, large-capacity power source. To meet such demands, a middle or large battery module electrically connected to a plurality of battery cells or a large battery pack electrically connected with battery modules is used.

As described above, a bus bar is used as a member for electrically connecting two or more battery cells or two or more battery modules, and the bus bar is a passage through which the current drawn from the battery cell moves.

Since the battery cell, the battery module, and the battery pack, which are fastened to the bus, are generally used for devices and devices that are frequently moved, the bus bars and the battery cells may be poorly fastened.

If the fastening state of the bus bar constituting the battery module by tightening the battery cell in the battery is poor, the resistance between the battery cell and the bus bar may increase, and the resistance of the cell and the bus bar may increase due to the energy of the battery Not only does it lead to a loss, but also generates heat, which increases the overall temperature of the battery, leading to ignition or explosion of the battery, which is also a serious problem.

Therefore, in order to prevent and solve the above problems, it is necessary to check the fastening state of the bus bar from time to time. As a method of confirming the fastening state of the bus bar, a method of checking the fastening state of the bus bar by measuring the voltage of the bus bar is widely .

As described above, Korean Patent Publication No. KR2014-0055065 is known as a technology for confirming the state of fastening of a bus bar. In the conventional technology, the difference between the voltage sum of the battery cells and the voltage between both ends of the bus bar is measured and the presence or absence of the bus bar fastening state is judged from the measured values. Is different from the technical idea of checking the fastening state of the bus bar.

In addition, in the prior art, there is a circuit for measuring the voltage of the bus bar at the time of charging and discharging instead of measuring in both directions of charging or discharging, so that the circuit configuration for checking the state of the bus bar is complicated and occupies a lot of space Respectively.

Therefore, the present invention provides an apparatus and method for confirming the fastening state of a bidirectional bus bar capable of measuring both the charging and discharging directions of the battery by measuring the voltage difference between the module bus bar and the module bus bar for confirming the fastening state of the bus bar.

Korean Unexamined Patent Publication No. 2014-0055065

The present invention provides an apparatus and method for checking the state of fastening of a bus bar by measuring the voltage of the bus bar.

The present invention provides an apparatus and method for confirming the fastening state of a bus bar by measuring the voltage of the bus bar with one device regardless of the charging or discharging state of the battery.

The present invention relates to an apparatus for verifying the state of a bus bar by measuring a voltage of a bus bar, comprising: a plurality of module bus bars; a voltage measuring unit for measuring a voltage between the plurality of module bus bars; And a BMS for confirming the fastening state of the module bus bar from the voltage value measured by the voltage measuring unit. [5] The bidirectional bus bar fastening state checking apparatus according to claim 1, .

A method for determining a fastening state of bus bars by measuring a voltage between battery module bus bars, the method comprising:

A step of increasing a reference voltage between bus bars by applying a predetermined boosting voltage between the bus bars, measuring a voltage between the bus bars, comparing the measured voltage with the boosted reference voltage, And determining a fastening state of the two-way bus bar.

The present invention relates to an apparatus and method for checking the state of fastening of a bus bar when a battery is charged and a method and an apparatus for checking the fastened state of a bus bar when discharging a battery, You can check the status.

Also, by using one integrated device and method that use different devices and methods when charging and discharging the battery, the structure is simplified, space utilization is increased, and the manufacturing cost of the battery pack can be reduced.

1 is a block diagram of a bidirectional bus bar engagement state confirmation apparatus of the present invention.
2 is a circuit diagram of a bidirectional bus bar fastening state checking apparatus according to the present invention.
FIG. 3 is an embodiment using the apparatus and method for checking the state of the bi-directional bus bar fastening state of the present invention.
4 is a flow chart of an apparatus and method for checking the state of the bi-directional bus bar engagement state of the present invention.

1. Basic structure of BMS and bus bar

In addition to automobile batteries, the role of the battery as an energy storage source is becoming more and more important, and thus a battery pack having a multi-module structure in which a plurality of battery modules are fastened is widely used.

The plurality of battery modules 200 includes a plurality of battery cells 210. The BMS 300 for efficiently managing the cell voltage measurement of each battery cell 210 and the balancing control of the battery cell 210, .

The BMS 300 includes a controller, and the controller collects information on the battery cells, and controls the battery cells according to information of the collected battery cells.

In general, the module bus bar 220 is used as a member necessary for electrical connection between the battery cell 210 and the battery module 200 and for connection with an external device to receive power from the battery cell.

The module bus bar 220 is a passage through which the current drawn from the battery cell 210 moves and the module bus bar 220 is connected to the power input part 221, the power output part 222 and the main body part 223 And the like.

The power input unit 221 receives a current from an output terminal of the battery cell 210. The power output unit 222 outputs a current received from the power input unit 221 of the battery module 200, To the external circuit and device connected to the bar 220. The main body 223 electrically connects the power input unit 221 and the power output unit 222.

2. Method for measuring the fastening state of the bus bar of the present invention

The general battery module 200 has a structure including the BMS 300 and the module bus bar 220. The entire battery module 200 is managed by the BMS 300, A plurality of battery cells 210 constituting a battery module 200 are connected to the battery module 220.

Since the plurality of battery cells are connected to the module bus bar to constitute the battery module, it is important to check the fastening state of the module bus bar in order to secure the output stability of the battery module.

The conventional method of checking the state of the module bus bar 220 is to calculate the difference between the sum of the voltages of the battery cells 210 connected to the module bus bar 220 and the voltage value across the module bus bar 220, The fastening state of the fastener 220 was confirmed.

In order to measure the voltage value at both ends of the module bus bar, since the flow of the current flowing through the module bus bar during charging and discharging are opposite to each other, the voltage measuring circuit between the module bus bar and the module bus bar Both voltage measurement circuits had to be configured separately.

In contrast, the present invention is not limited to calculating the difference between the sum of the voltages of the battery cells and the voltage between both ends of the module bus bar, but the module bus bar 220 And a module bus bar 220. The module bus bar 220 is connected to the module bus bar 220 by a cable.

In the present invention, a device for confirming the state of connection of the module bus bar 220 at the time of battery charging and a device for checking the state of connection of the module bus bar 220 at the time of battery discharge are conventionally integrated, Thereby confirming the fastened state of the bus bar irrespective of the charging or discharging state of the battery.

Hereinafter, a bidirectional bus bar fastening state checking apparatus 100 according to the present invention will be described in detail with reference to FIG.

The bidirectional bus bar connection state confirmation apparatus 100 includes a voltage measurement unit 110 for measuring a voltage between module bus bars 220 and a boosted voltage for boosting a reference voltage between the module bus bars 220 And a step-up voltage supplier 120 for supplying the boost voltage.

The voltage measuring unit 110 of the bidirectional bus bar connection state checking apparatus 100 measures the voltage between the module bus bars 220 constituting the battery module 200 by connecting the battery cells 210, The control unit of the BMS 300 compares the measurement value with the reference voltage value. When the measurement value and the reference voltage value are within a predetermined error range, the control unit of the BMS 300 compares the measurement value and the reference voltage value, If the difference between the measured value and the reference voltage value is outside a predetermined error range, it is determined that the fastening state of the module bus bar 220 is poor.

In order to allow the voltage measurement unit 110 to measure the voltage between the module bus bars 220 in both the charging and discharging directions of the battery, the voltage-boosting voltage supply unit 120 of the bidirectional bus- When the connection state of the module bus bars 220 is normal, the voltage measuring unit 110 of the bidirectional bus bar check unit 110 applies a boost voltage for boosting the reference voltage measured at 0 V to a predetermined reference voltage .

Hereinafter, when all the fastened state of the module bus bar 220 is normal, the reference voltage between the module bus bars, which is measured at 0 V by the voltage measuring unit 110 of the bidirectional bus bar fastening state checking apparatus, And the voltage is increased to a predetermined reference voltage.

When there is no device or method for applying a boosted voltage as in the prior art, when the fastening state of the module bus bar is normal, the voltage between the module bus bars 220 is measured to be 0 V, The potential difference between the module bus bars is measured and it can be understood that the fastening state of the module bus bar is poor.

If there is a module bus bar 220 having a poor connection state when the battery is in a charged state, the potential difference between the module bus bar 220 in the normally engaged state and the module bus bar 220 in the improperly connected state is measured as it is It can be confirmed that the fastening state of the bus bar is poor.

However, when there is a module bus bar 220 having a poor connection state in a discharged state of the battery, the voltage of the module bus bar 220 in the normally engaged state and the (-) potential of the module bus bar 220 in the poorly- (-) potential difference is 0 V due to the characteristic of the connection state check circuit of the module bus bar 220, it is determined whether the voltage difference between the module bus bar 220 and the module bus bar 220 is 0 V, It is not possible to distinguish whether the bus bar 220 is in a poor state of connection and the (-) potential difference is 0 V, so that it is impossible to accurately check the state of the connection of the module bus bar 220.

Accordingly, in the present invention, since the two cases in which the voltage between the module bus bars 220 is measured at 0 V when the battery is discharged are not distinguished, a problem that the state of the module bus bar 220 can not be confirmed can be solved A predetermined boost voltage is applied to boost the reference voltage 0V measured between the module bus bars 220 in the normally engaged state to a predetermined reference voltage.

If the voltage between the module bus bars 220 is measured when the reference voltage is raised to a predetermined reference voltage by the step-up voltage, if the two module bus bars 220 are in a normal state, The reference voltage value is measured.

On the other hand, when the battery bus 220 is in a poorly fastened state in a charged state,

(The boosted reference voltage) + (the potential difference between the module bus bar and the module bus bar) is measured, and when the battery bus is in a discharged state and the module bus bar 220 is in a poor state,

(The boosted reference voltage) - (potential difference between the module bus bar and the module bus bar)

Value can be measured to measure the voltage across module bus bars 220 in both the charge and discharge directions.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be understood, however, that the invention is not limited to the disclosed embodiments, but is capable of other various forms of implementation, and that these embodiments are provided so that this disclosure will be thorough and complete, It is provided to let you know completely.

3. Embodiments of the Invention

When a battery pack (not shown) having a structure in which a plurality of battery modules 200 are connected as shown in FIG. 1 is used in a hybrid vehicle, the battery pack (not shown) In the case of charging the battery pack (not shown) through regenerative braking in which the electric motor serves as a generator at the time of braking of the vehicle or discharging power from the engine by fuel combustion at the time of braking of the vehicle, Thereby charging the battery pack (not shown).

In the case of a battery pack (not shown), which is frequently charged and discharged as described above, in order to confirm the fastened state of the module bus bar 220 in both charging and discharging directions, the battery cells 210 are connected to the battery module 220, The voltage between the module bus bars 220 constituting the module bus bar 220 is measured to check the fastening state of the module bus bar 220 in both charging and discharging directions.

Referring to FIG. 2, the bidirectional bus bar fastening state checking apparatus 100 includes a bus bar voltage measuring unit 110 including a resistor 112 and a resistor 111 between module bus bars, And a power supply unit 120 for supplying a step-up voltage for stepping up the reference voltage of the power supply unit 120.

The accuracy of the measurement value is determined by the ratio of the resistance (112) to the resistance value (111) of the bidirectional bus bar fastening state checking apparatus 100 according to the present invention. Is determined.

The bus bar voltage calculation method of the bidirectional bus bar engagement state confirmation device

[수식1]

[Equation 1]

[수식2]

[Equation 2]

Can be expressed by Equations (1) and (2).

The first battery module 200 is connected to the first module bus bar power input part 221 so that the voltage of 10 V is output from the first module bus bar power output part 222 It is set to be. The second battery module 200 is configured such that the battery cells 210 are connected to the second module bus bar power input part 221 so that a voltage of 10 V is output from the second module bus bar power output part 222.

The resistance value of the bidirectional bus bar fastening state checking apparatus 100 according to the present invention is set to 10 MΩ respectively and the boost voltage 113 of 3.3 V is further added between the module bus bars And the reference voltage of the circuit is raised to 1.65 V to check the state of the bus bar. The measured values according to the state of the bus bar are as follows.

When both of the two module bus bars 220 are in a normal state, the voltage between the two bus bars 220 is increased by applying a step-up voltage to the device to increase the reference voltage to 1.65 V The measured value is transmitted to the control unit of the BMS 300 and it is determined that the state of the module bus bar 220 is normal.

When the output of the module bus bar 220 is reduced from 10V to 8.5V due to a poor coupling of the first module bus bar 220, when the battery is being charged, the first module bus bar 220 The voltage difference between the two module bus bars 220 is 1.5 V. In the voltage measuring unit 110 of the bidirectional bus bar connection state checking apparatus of the present invention, the voltage value between the two module bus bars 220 is 1.65 + 1.5 = 3.65 V, and the voltage value between the measured module bus bars 220 is transmitted to the control unit of the BMS 300 to measure the voltage value and the boosted reference voltage between the module bus bars 220 It is judged that the fastening state is poor.

On the other hand, when the battery is being discharged, the potential difference between the first module bus bar 220 and the second module bus bar 220 is 1.5 V, but the direction of the current is opposite to that during charging of the battery, In the measurement unit 110 of the bidirectional bus bar fastening state checking apparatus of the present invention, the voltage value between the two module bus bars 220 is measured as 1.65-1.5 = 0.15 V, and the measured module bus bars 220 May be transmitted to the controller of the BMS 300 and compared with the measured voltage value and the boosted reference voltage between the module bus bars 220 to determine that the connection state is poor.

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 limited to the disclosed exemplary embodiments. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention.

100: Bus bar check condition
110: Checking the state of bus bar connection
120: Checking the state of the bus bar connection device Step-up voltage supply part
200: Battery module
210: battery cell
220: Module bus bar

Claims (7)

It measures the voltage of the bus bar and checks the state of the bus bar.
A plurality of module bus bars;
A voltage measuring unit for measuring a voltage between the plurality of module bus bars;
A boost voltage application unit for applying a voltage for boosting a reference voltage between the module bus bars;
A BMS for confirming the state of connection of the module bus bar from the voltage measured by the voltage measuring unit;
And a controller for controlling the operation of the bidirectional bus bar. The apparatus according to claim 1, wherein the step-up voltage applying unit applies a predetermined step-up voltage between the battery module bus bars to step up the reference voltage between the module bus bars. 2. The apparatus according to claim 1, wherein the voltage measuring unit measures a potential difference between the module bus bars whose reference voltage is stepped up by a predetermined step-up voltage. 4. The method of claim 3, wherein the BMS comprises:
And comparing the measured voltage value of the voltage measuring unit with the boosted reference voltage value to determine the fastening state of the module bus bars. 4. The method according to claim 3 or 4,
Wherein the BMS determines that the fastening state of the module bus bars is not normal when the difference between the measured voltage of the voltage measuring unit and the boosted reference voltage is greater than a predetermined error range, Identification device. A method for determining a fastening state of bus bars by measuring a voltage between battery module bus bars,
Increasing a reference voltage between bus bars by applying a predetermined boosting voltage between the bus bars;
Measuring a voltage between the bus bars;
Comparing the measured voltage with the boosted reference voltage to determine a fastening state of the bus bars;
And determining whether or not the two-way bus bar is connected. The method according to claim 6,
The step of comparing the measured voltage with the boosted reference voltage to determine the state of bus bars,
When the difference between the boosted reference voltage and the measured voltage falls within a predetermined error range, it is determined that the connection state of the module bus bar is normal;
When the battery is charged, if the measured voltage is higher than the boosted reference voltage, it is determined that the fastening state of the module bus bar is poor.
When the battery is discharged, if the measured voltage is lower than the boosted reference voltage, it is determined that the fastening state of the module bus bar is poor;
The bus bar is connected to the bus bar.

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