KR20230109802A - Apparatus for inspecting battery pack protection circuit - Google Patents

Abstract

The present invention relates to an apparatus for inspecting a protection circuit composed of n+1 channels in which n (n is a natural number of 2 or more) or more battery cells are connected and monitoring charging and discharging of each of the n battery cells. A power supply unit that sequentially provides a driving voltage to n + 1 channels to operate the protection circuit, a current sensing unit that outputs a current signal by detecting a current flowing in the protection circuit as the driving voltage is applied, and a microcomputer for generating analysis information on a short circuit or short circuit state in the protection circuit using the sensed current signal.

Description

Battery pack protection circuit inspection device {Apparatus for inspecting battery pack protection circuit}

The present invention relates to an inspection of a battery pack protection circuit.

Recently, rapid charging is a topic in which research and development are actively occurring in the field of electronic devices using secondary batteries. Rapid charging is a method of supplying a higher current than standard charging so that charging is completed quickly. Rapid charging has the effect of shortening the waiting time for the user to charge by charging the battery of the terminal to be charged in a short time.

In the case of an electric vehicle, which has recently become an issue, the charging method is divided into slow charging and rapid charging. In the case of slow charging, it generally takes more than 8 hours to charge, and in the case of rapid charging, it aims to be fully charged within 30 minutes. Even in the case of small mobile devices such as electric bicycles or electric kickboards, chargers with a charging current of around 2A in the past were mostly used, but recently, rapid chargers with a charging current of 4 to 5A or more have been popularized.

On the other hand, small battery packs used in terminals such as smartphones are composed of one cell and only need to perform protection against the charger voltage, but large-capacity battery packs for vehicles are often composed of multiple cells to improve charging and discharging characteristics.

In general, a battery pack management system composed of a plurality of cells rectifies AC power supplied from an external power supply source into DC power and supplies it to the battery cells, and adjusts the current supplied to the battery cells or drains the current stored in the battery cells. A protection circuit, such as a BMS (Battery Management System), is provided to control the charging and discharging state of the battery cells.

Since a plurality of battery cells may have slightly different internal electromotive force and internal impedance of an internal power supply source, voltage and current characteristics are different in a no-load state, a discharge state, and a charge state.

BMS is a means of measuring the voltage of battery packs used in smartphones, electric bicycles, electric scooters, electric kickboards, etc., and managing them so that they are not damaged and maintained in optimal conditions during the charging and discharging process.

If the operation of the BMS is not performed accurately, the lifespan of the battery pack may be shortened or an accident such as fire or explosion may occur. Therefore, a device for inspecting whether the operation of the BMS is performed correctly is used.

In the case of protection circuits for smartphones (single cell) or laptop protection circuits (3-4 cells), which are mass-produced, exclusive inspection equipment costing tens of millions of won is introduced and applied.

KR 10-1270798 B1

The present invention provides an inspection device for a battery pack protection circuit capable of quickly inspecting a BMS, which is a protection circuit in a battery pack system.

In addition, the present invention provides an inspection device for a battery pack protection circuit by detecting a leakage current of the protection circuit.

The problems to be solved by the present invention are not limited to those mentioned above, and other problems to be solved that are not mentioned will be clearly understood by those skilled in the art from the description below.

In order to solve the problem to be solved, an inspection apparatus for a battery pack protection circuit according to an embodiment of the present invention is an apparatus for inspecting a protection circuit composed of n + 1 channels in which n (n is a natural number of 2 or more) or more battery cells are connected to control charging and discharging through monitoring of each of the n battery cells, a connection part connected to a connector of the protection circuit composed of n + 1 battery-side terminals connected to the n battery cells, and a connection terminal connected to each of the n + 1 battery-side terminals, A power supply unit that sequentially applies a driving voltage to each of the negative connection terminals to sequentially provide a driving voltage to n+1 channels of the protection circuit to operate the protection circuit, and a current sensing unit that outputs a current signal by detecting a current flowing in the protection circuit as the driving voltage is applied, and a microcomputer that generates analysis information about a short circuit or short circuit state in the protection circuit using the sensed current signal.

According to an embodiment of the present invention, the power supply unit includes a power supply unit that provides the driving voltage, a switching unit that is connected between the power supply unit and the connection unit, connects one of the connection terminals of the connection unit to the power supply unit, applies a driving voltage to one of the connection terminals, provides a driving voltage to a channel connected to a battery-side terminal connected to the one connection terminal, operates the protection circuit, and changes the connection terminal connected to the power supply unit based on a switching control signal, wherein the micom includes a predetermined time interval It is possible to generate a switching control signal for changing a connection terminal connected to the power supply unit.

According to an embodiment of the present invention, the switching unit may be a relay switch.

According to an embodiment of the present invention, the signal processing unit includes a differential amplifier that detects a current flowing in the protection circuit after applying a driving voltage through the connection unit, and then amplifies and outputs the current flowing through comparison with a reference signal, and an A/D conversion unit that converts the signal output from the differential amplifier into a digital signal and outputs the digital signal to the microcomputer. You can.

According to an embodiment of the present invention, the test apparatus blinks according to a predetermined notification signal and further includes a notification unit composed of LEDs corresponding to the number of the battery-side terminals, and the microcontroller may apply the alarm signal to the notification unit for blinking an LED corresponding to a battery-side terminal connected to a channel to which the driving voltage is applied when a short circuit or short circuit state is detected in a channel to which the driving voltage is applied.

According to an embodiment of the present invention, the test device further includes a communication unit for connecting an external device and the test device through a wired or wireless network, and the microcomputer transmits the digital signal or the analysis information to the device through the communication unit.

According to the above-described problem solving means of the present invention, after removing the battery pack from the protection circuit for protecting a battery pack composed of at least two or more battery cells, by providing a device capable of testing by connecting to a connector of the protection circuit connected to the battery pack, since it is possible to perform an inspection for each channel (i.e., circuit) connected to each battery cell, the inspection accuracy can be improved, and operator convenience and inspection time can be shortened.

1 is a diagram for explaining the configuration of a protection circuit to which a test apparatus according to an embodiment of the present invention is applied.
2 is a diagram for explaining a connection structure between a test device and a protection circuit according to an embodiment of the present invention.
3 is a diagram showing the configuration of a protection circuit inspection device according to an embodiment of the present invention.
4 is a diagram showing the configuration of a signal processing unit in a testing device according to an embodiment of the present invention.
5 is a diagram illustrating that a test device according to an embodiment of the present invention transmits information by communicating with the outside.

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. The detailed descriptions that follow are provided to provide a comprehensive understanding of the methods, devices and/or systems described herein. However, this is only an example and the present invention is not limited thereto.

In describing the embodiments of the present invention, if it is determined that the detailed description of the known technology related to the present invention may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. In addition, terms to be described later are terms defined in consideration of functions in the present invention, which may vary according to the intention or custom of a user or operator. Therefore, the definition should be made based on the contents throughout this specification. Terminology used in the detailed description is only for describing the embodiments of the present invention and should in no way be limiting. Unless expressly used otherwise, singular forms of expression include plural forms. In this description, expressions such as “comprising” or “comprising” are intended to indicate certain characteristics, numbers, steps, operations, elements, parts or combinations thereof, and should not be construed to exclude the existence or possibility of one or more other characteristics, numbers, steps, operations, elements, parts or combinations thereof other than those described.

Hereinafter, an inspection apparatus and method for a protection circuit, that is, a battery management system (BMS) will be described with reference to the accompanying drawings.

1 is a diagram for explaining the configuration of a protection circuit to which a test device according to an embodiment of the present invention is applied, FIG. 2 is a diagram for explaining a connection structure between a test device and a protection circuit according to an embodiment of the present invention, FIG. 3 is a diagram showing the configuration of a test device for a protection circuit according to an embodiment of the present invention, and FIG.

As shown in FIGS. 1 and 2 , the protection circuit 100 connected to the inspection device 200 according to an embodiment of the present invention may include a connector 110 composed of battery-side terminals (B+, B1, B2, B3, B-) connected to a plurality of battery cells 10, charger-side terminals (P+, P-) connected to an external power source to receive external power, and a controller 120 that controls the operation of the protection circuit 100. there is For example, when four battery cells 10 are connected, the connector 110 may be composed of five battery-side terminals (B+, B1, B2, B3, B-), one battery cell 10 is connected between the battery-side terminals of B+ and B1, and the battery cell 10 is connected between the battery-side terminals of B1 and B2. , B2, B3, B-).

The controller 120 charges the battery cells 10 connected to the battery terminals B+, B1, B2, B3, and B- with external power supplied through the charger terminals P+ and P-, or discharges each battery cell 10, and monitors each battery cell 10 through the battery terminals B+, B1, B2, B3, and B-.

In particular, in the protection circuit 100 according to the embodiment of the present invention, each battery-side terminal (B+, B1, B2, B3, B-) of the connector 110 may be connected to the controller 120 through each channel 20 in which a circuit for charging and discharging and monitoring each battery cell 10 is formed.

Meanwhile, the inspection device 200 according to the embodiment of the present invention can be disconnected from the battery pack 15 composed of the battery cells 10, that is, connected to the protection circuit 100 separated through the connector 110. That is, the test device 200 connects the connector 110 of the protection circuit 100 disconnected from the battery pack 15 through the separation of the connector 110 and the connection part 210, thereby connecting to the protection circuit 100 It is possible to perform an inspection.

In addition, as shown in FIG. 3, the inspection device 200 is sequentially connected to the battery-side terminals (B+, B1, B2, B3, B-) of the connector 110 at a predetermined time (t) interval to check the state of the protection circuit 100, for example, a short circuit or a short circuit. Specifically, the test device 200 is connected to the battery-side terminal B+, applies a driving voltage necessary for driving the protection circuit 100 through the battery-side terminal B+, and then senses a corresponding current signal to check the state of the protection circuit 100. As a predetermined time (t) elapses, it is connected to the battery-side terminal B1, applies a driving voltage necessary for driving the protection circuit 100 through the battery-side terminal B1, and then senses a corresponding current signal to protect circuit 1 00), the channel 20 in the protection circuit 100 connected to each battery-side terminal (B+, B1, B2, B3, B-), that is, the overall operation of the protection circuit 100. The state of the circuit can be checked.

To this end, the inspection device 200 according to an embodiment of the present invention may include a connection unit 210 connected to the connector 110, a power supply unit 220, a current sensing unit 221, a signal processing unit 225, and a microcomputer 230.

The connection unit 210 may have connection terminals C+, C1, C2, C3, and C- connected to portions corresponding to the battery-side terminals B+, B1, B2, B3, and B- provided in the connector 110.

The power supply unit 220 sequentially applies a driving voltage to the connection terminals (C+, C1, C2, C3, C-) at predetermined time intervals, and supplies the driving voltage to the protection circuit 100 through the battery-side terminals (B+, B1, B2, B3, B-) connected to the connection terminals (C+, C1, C2, C3, C-) to operate the protection circuit 100.

To this end, the power supply unit 220 may include a power supply unit 222 that generates power required for the driving voltage and a switching unit 224 that sequentially connects the connection terminals (C+, C1, C2, C3, and C-) of the connection unit 210 to the power supply unit 222 to provide a driving voltage through a switching operation at predetermined time intervals. That is, by providing a driving voltage to the connection terminal C+, the power supply unit 220 applies the driving voltage to the channel 20 connected to the battery side terminal B+ of the protection circuit 100 through the battery side terminal B+ of the connector 110 connected to the connection terminal C+ to operate the protection circuit 100, and as a predetermined time elapses (i.e., a switching control signal from the microcomputer 230 is applied), based on the switching operation of the switching unit 224 By connecting the power supply unit 222 to the connection terminal C1 and applying a driving voltage to the channel 20 connected to the battery side terminal B1 of the protection circuit 100 through the battery side terminal B1 of the connector 110 connected to the connection terminal C1 to operate the protection circuit 100, the protection circuit 100 is operated through each channel 20 connected to each battery side terminal (B+, B1, B2, B3, B-) of the protection circuit 100. can make it

The switching unit 224 may perform a switching operation based on a switching control signal provided from the microcomputer 230 .

Meanwhile, the current sensing unit 221 may sense a current signal as the protection circuit 100 operates by the driving voltage and then provide the current signal to the signal processing unit 225 .

In an embodiment of the present invention, the current sensing unit 221 may be disposed between the power supply unit 222 and the switching unit 224 .

On the other hand, as shown in FIG. 4, the signal processing unit 225 may include a differential amplifier 226 that receives a current signal and a preset reference signal and amplifies a current signal greater than or equal to the reference signal Vcc, and an A/D converter 227 that converts the current signal amplified by the differential amplifier 226 into a digital signal and outputs it to the microcomputer 230. Specifically, the signal processing unit 225 receives the current signal sensed by the current sensing unit 221 and amplifies it when the voltage across the resistor R is greater than or equal to the reference signal Vcc, and outputs the amplified signal to the A/D converter 227.

The microcomputer 230 determines whether leakage current is detected through analysis of the digital signal provided from the A/D converter 227, and when the leakage current is detected, an alarm signal corresponding thereto may be applied to the notification unit 235. Accordingly, the notification unit 235 may notify the inspector of the state of the protection circuit 100 by outputting LED flashing, beeping, etc. based on the alarm signal.

In particular, in the embodiment of the present invention, the notification unit 235 may be composed of a plurality of LEDs 235/1 to 235/n to inform the status of each channel 20, and based on an alarm signal applied from the microcomputer 230, only one of the plurality of LEDs 235/1 to 235/n may blink. Specifically, the micom 230 applies a switching control signal to the switching unit 222 so that a driving voltage is applied to B+ among the battery-side terminals, and then, as a result of analyzing the digital signal output from the signal processing unit 225, it is recognized that an abnormality has occurred in the state of the protection circuit 100. As a result, a notification signal may be applied to the LED 235/1 corresponding to the battery-side terminal of B+ to make it blink.

On the other hand, the microcomputer 230 according to the embodiment of the present invention is connected to an external device 300, for example, any one of a smartphone, computer, laptop, and server through a wired or wireless network through the communication unit 240 to transmit a digital signal or an analysis result.

When a digital signal is transmitted, the device 300 stores a program 310 for analyzing the digital signal, and as the digital signal is received, the program 310 is driven to analyze the digital signal, and then the corresponding analysis result, that is, information about the state of the protection circuit 100, can be displayed on a display (not shown).

When the device 300 is a smartphone, the test device 200 can access a mobile communication system, which is a wireless network, and transmit a digital signal or an analysis result to a pre-registered smartphone through the mobile communication system.

To this end, the communication unit 240 in the test apparatus 200 includes RF, 3rd Generation Partnership Project (3GPP) network, Long Term Evolution (LTE) network, 5th Generation Partnership Project (5GPP) network, World Interoperability for Microwave Access (WIMAX) network, Internet, Local Area Network (LAN), Wireless Local Area Network (LAN), Wide Area Network (WAN), Personal Area Network (PAN), and Bluetooth (Bluetooth). tooth) network, NFC network, satellite broadcasting network, analog broadcasting network, DMB (Digital Multimedia Broadcasting) network, etc. may be provided with a communication chip connectable.

The above description is merely an example of the technical idea of the present invention, and various modifications and variations can be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments expressed in the present invention are not intended to limit the technical idea of the present invention, but to explain, and the scope of the present invention is not limited by these embodiments. The protection scope of the present invention should be construed according to the claims below, and all technical ideas that are equivalent or within the scope of equivalents should be construed as being included in the scope of the present invention.

100: protection circuit
200: inspection device

Claims (6)

In the apparatus for inspecting a protection circuit composed of n + 1 channels for controlling charging and discharging through monitoring of each of the n battery cells connected to n (n is a natural number of 2 or more),
A connection portion connected to a connector of the protection circuit composed of n+1 battery-side terminals connected to the n battery cells and composed of connection terminals connected to each of the n+1 battery-side terminals;
A power supply unit for operating the protection circuit by sequentially applying a driving voltage to each of the connection terminals of the connection unit and sequentially providing a driving voltage to n+1 channels of the protection circuit;
a current sensing unit outputting a current signal by sensing a current flowing in the protection circuit as the driving voltage is applied;
A battery pack protection circuit inspection device including a microcomputer for generating analysis information on a short circuit or short circuit state in the protection circuit using the sensed current signal.
According to claim 1,
The power supply unit,
a power supply unit providing the driving voltage;
It is connected between the power supply unit and the connection unit, connects any one of the connection terminals of the connection unit to the power supply unit, applies a driving voltage to any one of the connection terminals, and provides a driving voltage to a channel connected to a battery side terminal connected to the one connection terminal to operate the protection circuit, and a switching unit that changes the connection terminal connected to the power supply unit based on a switching control signal,
Wherein the microcomputer generates a switching control signal for changing a connection terminal connected to the power supply unit at a predetermined time interval.
According to claim 2,
The switching unit,
Inspection device for battery pack protection circuit, which is a relay switch.
According to claim 1,
The signal processing unit,
A differential amplifier for amplifying and outputting a current flowing in the protection circuit after applying a driving voltage through the connection part, and then comparing it with a reference signal;
An A/D conversion unit converting a signal output from the differential amplifier into a digital signal and outputting the converted digital signal to the microcomputer;
The microcomputer determines whether there is an overcurrent in the protection circuit through analysis of the digital signal output by the A / D conversion unit, and generates analysis information about a short circuit or short circuit in the protection circuit.
According to any one of claims 1 to 4,
The inspection device,
Further comprising a notification unit composed of LEDs blinking according to a predetermined notification signal and corresponding to the number of the battery-side terminals,
The micom detects a short circuit or short circuit in the channel to which the driving voltage is applied, and the alarm signal for blinking an LED corresponding to a battery-side terminal connected to the channel to which the driving voltage is applied is applied to the notification unit. Testing device of a battery pack protection circuit.
According to any one of claims 1 to 4,
The inspection device,
Further comprising a communication unit for connecting an external device and the test device through a wired or wireless network,
The microcomputer,
A battery pack protection circuit inspection device for transmitting the digital signal or the analysis information to the device through the communication unit.

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