KR102690979B1 - Apparatus and method for diagnosing a power switch - Google Patents

Abstract

A power switch diagnostic device and method are disclosed. According to an embodiment of the present invention, a power switch diagnostic device includes a DC-DC voltage converter configured to output a driving voltage using an input voltage; a power switch that applies or blocks the input voltage to the DC-DC voltage converter; When the driving voltage is applied and driven and a shutdown signal commanding shutdown is input, a control unit that outputs a hold signal and an invalid trigger signal to induce the power switch to maintain an operating state in a turn-on state; And when the driving voltage is applied and driven and the invalid trigger signal is input, the control unit outputs a reset signal to induce the control unit to stop outputting the hold signal so that the operating state of the power switch is changed to a turn-off state. and a watchdog timer, wherein when the reset signal is input, the control unit stops outputting the hold signal and determines whether the power switch is broken based on whether the driving voltage is applied and whether the shutdown signal is input. can be diagnosed.

Description

Power switch diagnostic device and method {APPARATUS AND METHOD FOR DIAGNOSING A POWER SWITCH}

The present invention relates to a power switch diagnostic device and method, and more specifically, to a power switch diagnostic device and method for diagnosing a failure of a power switch that turns on or off power to a battery management device.

Recently, as the demand for portable electronic products such as laptops, video cameras, and portable phones has rapidly increased, and as the development of electric vehicles, energy storage batteries, robots, and satellites has begun, the need for high-performance batteries capable of repeated charging and discharging has increased. Research is actively underway.

Currently commercialized batteries include nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, and lithium batteries. Among these, lithium batteries have almost no memory effect compared to nickel-based batteries, so they can be freely charged and discharged, and have a very high self-discharge rate. It is attracting attention due to its low and high energy density.

Battery packs mounted on electric vehicles, etc. generally include at least one battery module. At this time, each battery module includes one or two or more battery cells connected in series.

The status of each battery module included in this battery pack is monitored by a battery management system (BMS). The battery management device may output signals for controlling balancing operations, cooling operations, charging operations, discharging operations, etc., based on parameters (e.g., voltage, current, temperature) monitored from each battery module.

This battery management device also operates by receiving power from the battery module, and the power output from the battery module is applied or cut off depending on the operating state of the power switch.

When the battery pack is not charged or discharged for a long time, such as when an electric vehicle is parked, the power switch is turned off and the battery management device operates in sleep mode to block unnecessary power consumption.

Conversely, when the battery pack is charged or discharged, such as when an electric vehicle is running or charging, the power switch turns on and the battery management device changes from sleep mode to wake-up mode and operates.

As such, since the power switch of the battery management device plays a role in controlling the operation mode of the battery management device, there is a need for technology that can diagnose whether the operating state is accurately controlled.

The present invention was made to solve the above problems, and provides a power switch diagnostic device and method for diagnosing whether a power switch that applies or blocks the driving voltage of a battery management device included in a battery pack is malfunctioning. The purpose.

Other objects and advantages of the present invention can be understood from the following description, and will be more clearly understood by practicing the present invention. In addition, it will be readily apparent that the objects and advantages of the present invention can be realized by means and combinations thereof indicated in the claims.

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

According to an embodiment of the present invention, a power switch diagnostic device includes a DC-DC voltage converter configured to output a driving voltage using an input voltage; a power switch that applies or blocks the input voltage to the DC-DC voltage converter; When the driving voltage is applied and driven and a shutdown signal commanding shutdown is input, a control unit that outputs a hold signal and an invalid trigger signal to induce the power switch to maintain an operating state in a turn-on state; And when the driving voltage is applied and driven and the invalid trigger signal is input, the control unit outputs a reset signal to induce the control unit to stop outputting the hold signal so that the operating state of the power switch is changed to a turn-off state. It can include a watchdog timer that does this.

Preferably, when the reset signal is input, the control unit stops outputting the hold signal and diagnoses whether the power switch is broken based on whether the driving voltage is applied and whether the shutdown signal is input. .

Preferably, the control unit may diagnose that a failure has occurred in the power switch when the driving voltage is input and the shutdown signal is input after the reset signal is input to stop outputting the hold signal.

Preferably, when a wake-up signal commanding wake-up is input, the control unit may output diagnostic data indicating a diagnosis result of whether the power switch is malfunctioning.

Preferably, the control unit may diagnose whether the watchdog timer is broken based on whether the reset signal is input within a predetermined threshold time from when the invalid trigger signal is output.

Preferably, the control unit may diagnose that a failure has occurred in the watchdog timer when the reset signal is not input within a predetermined threshold time from when the invalid trigger signal is output.

Preferably, when a wake-up signal commanding wake-up is input, the control unit may output diagnostic data indicating a diagnosis result of whether the watchdog timer is malfunctioning.

According to another embodiment of the present invention, a battery management device may include the power switch diagnostic device.

According to another embodiment of the present invention, a battery pack may include the power switch diagnostic device.

According to another embodiment of the present invention, a power switch diagnosis method includes: a DC-DC voltage converter configured to output a driving voltage using an input voltage; a power switch that applies or blocks the input voltage to the DC-DC voltage converter; a control unit driven by applying the driving voltage; A power switch diagnostic device including a watchdog timer driven by applying the driving voltage can be used to diagnose whether the power switch is malfunctioning.

The power switch diagnosis method includes the steps of outputting a hold signal and an invalid trigger signal to induce the power switch to maintain an operating state in a turned-on state when a shutdown signal commanding shutdown is input to the control unit; When the invalid trigger signal is input to the watchdog timer, outputting a reset signal that induces the control unit to stop outputting the hold signal so that the operating state of the power switch is changed to a turn-off state; And when the reset signal is input, the control unit stops outputting the hold signal and diagnoses whether the power switch is broken based on whether the driving voltage is applied and whether the shutdown signal is input. can do.

The step of diagnosing whether the power switch is malfunctioned includes determining that a malfunction has occurred in the power switch when the control unit stops outputting the hold signal when the reset signal is input, the driving voltage is input, and the shutdown signal is input. It may include the step of diagnosing

According to at least one of the embodiments of the present invention, it is possible to diagnose whether a power switch that applies or blocks a driving voltage of a battery management device included in a battery pack is malfunctioning.

In particular, when a shutdown signal that causes the operating state of the power switch to change to the turn-off state is input to the control unit from the outside, the control unit first outputs a hold signal that induces the operating state of the power switch to remain in the turn-on state, and then outputs a watch signal. If the driving voltage is applied even after stopping the output of the hold signal according to the reset signal input from the dock timer unit, it is diagnosed as a failure in the power switch, so it is possible to diagnose the failure of the power switch before the battery management device is shut down. .

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

The following drawings attached to this specification illustrate preferred embodiments of the present invention, and serve to further understand the technical idea of the present invention together with the detailed description of the invention described later, so the present invention includes the matters described in such drawings. It should not be interpreted as limited to only .
1 is a diagram showing the functional configuration of a battery pack according to an embodiment of the present invention.
FIG. 2 is a diagram showing the functional configuration of the battery management device of FIG. 1.
Figure 3 is a flowchart showing a method for diagnosing a power switch according to another embodiment of the present invention.
Figures 4 and 5 are timing charts showing the operation of a standard watchdog timer that can be used as the watchdog timer of Figure 2.
FIG. 6 is a timing chart showing the operation of a window watchdog timer that can be used as the watchdog timer of FIG. 2.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, the terms or words used in this specification and claims should not be construed as limited to their usual or dictionary meanings, and the inventor should appropriately define the concept of terms in order to explain his or her invention in the best way. It should be interpreted as meaning and concept consistent with the technical idea of the present invention based on the principle of definability.

Accordingly, the embodiments described in this specification and the configurations shown in the drawings are only one of the most preferred embodiments of the present invention and do not represent the entire technical idea of the present invention, so at the time of filing this application, various alternatives are available to replace them. It should be understood that equivalents and variations may exist.

Additionally, when describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description will be omitted.

Terms containing ordinal numbers, 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 limit the components by such terms.

Throughout the specification, when it is said that a part “includes” a certain element, this does not mean that other elements are excluded, but that it may further include other elements, unless specifically stated to the contrary. Additionally, terms such as <control unit> used in the specification refer to a unit that processes at least one function or operation, and may be implemented as hardware, software, or a combination of hardware and software.

Additionally, throughout the specification, when a part is said to be "connected" to another part, this refers not only to the case where it is "directly connected" but also to the case where it is "indirectly connected" with another element in between. Includes.

Hereinafter, the power switch diagnostic device 100 according to an embodiment of the present invention will be described.

Figure 1 is a diagram showing the functional configuration of a battery pack 10 according to an embodiment of the present invention.

Referring to FIG. 1 , the battery pack 10 includes a battery module 20, a contactor 30, and a battery management device 100.

The battery module 20 includes a positive terminal (B+), a negative terminal (B+), and at least one battery cell 21. When the battery module 20 includes a plurality of battery cells 21, the plurality of battery cells 21 may be connected to each other in series and/or parallel. Representative battery cells 21 include lithium ion batteries, lithium polymer batteries, nickel cadmium batteries, nickel hydrogen batteries, and nickel zinc batteries. Of course, the type of cell is not limited to the types listed above, and is not particularly limited as long as it can be repeatedly charged and discharged.

The contactor 30 is installed in the high current path of the battery pack 10 to control the charge/discharge current of the battery pack 10. The high current path of the battery pack 10 is a path between the positive terminal (B+) of the battery module 20 and the positive terminal (P+) of the battery pack 10, and the negative terminal (B-) of the battery module 20. It may include a path between the negative terminal (P-) of the battery pack 10. In Figure 1, the contactor 30 is shown as installed between the positive terminal (P+) of the battery pack 10 and the positive terminal (B+) of the battery module 20, but the installation location of the contactor 30 is It is not limited to this. For example, the contactor 30 may be installed between the negative terminal (P-) of the battery pack 10 and the negative terminal (B-) of the battery module 20.

The contactor 30 is turned on or turned off according to a switching signal from the battery management device 100, thereby opening and closing the flow of current through the battery module 20.

The battery management device 100 is operably coupled to the battery module 20 and the contactor 30 and can individually control the operations of the battery module 20 and the contactor 30. The battery management device 100 individually measures the voltage, current, and/or temperature of the battery module 20, and performs various predetermined functions (e.g., cell balancing, It is configured to selectively execute at least one of charging and discharging).

The battery management device 100 receives a control signal from the external device 1 through two-way communication with the external device 1 (e.g., ECU of an electric vehicle), and provides diagnostic data indicating a diagnosis result to the external device 1. can be transmitted.

FIG. 2 is a diagram showing the functional configuration of the battery management device 100 of FIG. 1.

Referring to FIG. 2 , the battery management device 100 includes a sensing unit 110, a communication unit 120, and a power switch diagnostic device 130.

The sensing unit 110 is configured to measure the operating parameters of the battery module 20. To this end, the sensing unit 110 includes at least one of a voltage sensor 111, a current sensor 112, and a temperature sensor 113. The voltage sensor 111 is configured to measure the terminal voltage of the battery module 20 and/or the cell voltage of each battery cell 21 included in the battery module 20. The terminal voltage of the battery module 20 corresponds to the potential difference between the positive terminal (B+) and the negative terminal (B-) of the battery module 20. The current sensor 112 may be electrically connected in series to the contactor 30 and is configured to measure the current flowing through the high current path of the battery pack 10. The temperature sensor 113 is configured to measure the temperature of the battery module 20. The sensing unit 110 may periodically transmit a sensing signal indicating the measured terminal voltage, cell voltage, current, and/or temperature to the power switch diagnostic device 130.

The communication unit 120 is configured to support two-way communication between the external device 1 and the battery management device 100. The communication unit 120 may be installed between the external device 1 and the battery management device 100 for electrical insulation between the external device 1 and the battery management device 100.

The communication unit 120 may include a first photo relay 121. The first photo relay 121 includes a first light source and a first photodetector, and configures commands transmitted from the external device 1 to the battery management device 100 in a form recognizable by the battery management device 100. Convert to signals. Specifically, the first light source converts each command transmitted from the external device 1 into a corresponding optical signal and outputs it. The first photodetector generates a control signal corresponding to the optical signal in response to the optical signal output from the first light source. The control signal generated by the first photodetector is applied to the first communication terminal (COM1) of the control unit 133, which will be described later. As an example, the first photo relay 121 may convert a shutdown command from the external device 1 into a shutdown signal. As another example, the first photo relay 121 may convert a wake-up command from the external device 1 into a wake-up signal. The shutdown command is for guiding the battery management device 100 from the wake-up mode to the shutdown mode. The wake-up command is intended to induce the battery management device 100 from the shutdown mode to the wake-up mode. In the shutdown mode, power consumption by the battery management device 100 is stopped. On the other hand, in the wake-up mode, the battery management device 100 operates using power supplied from the battery module 20 or an external power source.

The communication unit 120 may further include a second photo relay 122. The second photo relay 122 includes a second light source and a second photodetector, and converts diagnostic data transmitted from the battery management device 100 to the external device 1 into a form that can be recognized by the external device 1. Convert to signals. Specifically, the second light source converts each diagnostic data transmitted from the battery management device 100 into a corresponding optical signal and outputs it. The second photodetector responds to the optical signal output from the second light source and generates a notification signal corresponding to the optical signal.

For example, an opto-coupler may be used as the first and second photo relays 121 and 122 described above.

Of course, the communication unit 120 may include another type of communication circuit that supports two-way communication with the external device 1 instead of the first and second photo relays 121 and 122.

The power switch diagnostic device 130 can individually perform diagnostic operations for the power switch 132. For example, the power switch diagnostic device 130 may diagnose a malfunction by checking whether the battery management device 100 is controlled in an operating state corresponding to each mode when operating in a wake-up mode or a shutdown mode.

For this purpose, the power switch diagnosis device 130 includes a DC-DC voltage converter 131, a power switch 132, a control unit 133, and a watchdog timer 134.

The DC-DC voltage converter 131 is configured to output a driving voltage using an input voltage. For this purpose, the DC-DC voltage converter 131 includes a power input terminal (IN) and a power output terminal (OUT). The power input terminal IN receives an input voltage from the battery module 20 or an external power source (eg, an auxiliary battery of an electric vehicle). That is, an input voltage from the battery module 20 or an external power source is applied to the power input terminal IN.

The power output terminal (OUT) outputs a driving voltage generated from the input voltage. That is, the DC-DC voltage converter 131 can generate a driving voltage using the input voltage applied to the power input terminal (IN) and output the generated driving voltage on the power output terminal (OUT). there is. The driving voltage output on the power output terminal (OUT) is for the control unit 133 and the watchdog timer 134. Of course, at least one of the control unit 133 and the watchdog timer 134 as well as the sensing unit 110 and the communication unit 120 may operate using the driving voltage.

The power switch 132 applies or blocks the input voltage to the DC-DC voltage converter 131. For this purpose, the power switch 132 is installed between the battery module 20 and the power input terminal (IN) of the DC-DC voltage converter 131.

The power switch 132 changes its operating state to a turn-on state or a turn-off state according to a control signal from the controller 133, thereby applying or blocking the input voltage to the DC-DC voltage converter 131. .

Specifically, the power switch 132 changes its operating state to the turn-on state only when the voltage of the control signal input from the control unit 133 is higher than the threshold voltage (e.g., 5V), and the control signal input from the control unit 133 is changed to the turn-on state. If the voltage of the signal is less than the threshold voltage or the control signal is not input, the operating state changes to the turn-off state.

When the operating state of the power switch 132 is changed to the turn-on state, the battery module 20 and the power input terminal (IN) of the DC-DC voltage converter 131 are electrically connected to supply an input voltage to the power input terminal (IN). This is approved.

Conversely, when the operating state of the power switch 132 is changed to the turn-off state, the power input terminal (IN) of the battery module 20 and the DC-DC voltage converter 131 are not electrically connected, and the power input terminal (IN) Input voltage is not applied to.

In terms of hardware, the control unit 133 includes application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), and microprocessors. It can be implemented using at least one of (microprocessors) and electrical units for performing other functions. The control unit 133 may have a built-in memory. The memory may additionally store data, commands, and software required for the overall operation of the power switch diagnostic device 130. Memory includes flash memory type, hard disk type, SSD type (Solid State Disk type), SDD type (Silicon Disk Drive type), multimedia card micro type, At least one of random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), and programmable read-only memory (PROM) It may include a type of storage medium.

The control unit 133 is driven by applying the driving voltage output from the DC-DC voltage converter 131. The control unit 133 can diagnose whether the power switch 132 is broken based on whether a driving voltage is applied and whether a shutdown signal is input.

For this purpose, the control unit 133 includes a power input terminal (POWER), a first communication terminal (COM1), a hold terminal (HOLD), a trigger terminal (TRIG), and a reset terminal (RES), and a second communication terminal ( COM2) may be further included.

The power input terminal (POWER) is electrically connected to the power output terminal (OUT) of the DC-DC voltage converter 131 and receives the driving voltage output through the power output terminal (OUT). The control unit 133 may operate using the driving voltage applied by the power input terminal (POWER).

The first communication terminal COM1 receives a control signal from the communication unit 120. When a shutdown signal commanding shutdown is input to the first communication terminal (COM1) through the communication unit 120, the control unit 133 sets the operating state of the power switch 132 to a turn-on state at the hold terminal (HOLD). Outputs a hold signal that induces to maintain . As described above, the hold signal may be a voltage higher than a threshold voltage (eg, 5V).

Accordingly, the power switch 132 receives the hold signal output from the hold terminal (HOLD) and maintains its operating state in the turn-on state.

As described above, the shutdown signal is related to a shutdown command from the external device 1 and may be a signal for commanding the control unit 133 and the battery management device 100 including the control unit 133 to shut down.

Additionally, when a shutdown signal is input to the first communication terminal (COM1) through the communication unit 120, the control unit 133 outputs an invalid trigger signal to the trigger terminal (TRIG).

The invalid trigger signal is for the control unit 133 to inform the watchdog timer 134 that it should end its operation, and the watchdog timer 134 sends a reset signal (e.g., 0V) is induced to be output.

The hold terminal (HOLD) is electrically connected to the power switch 132 and selectively outputs a hold signal. The hold terminal (HOLD) may be commonly electrically connected to the first communication terminal (COM1). In response to the shutdown signal, the control unit 133 may continuously output a hold signal on the hold terminal (HOLD) for at least a predetermined reference time. The power switch 132 applies an input voltage to the DC-DC voltage converter 131 while a hold signal higher than a threshold voltage (eg, 5V) is input. Subsequently, the DC-DC voltage converter 131 can continuously output the driving voltage generated using the input voltage on the power output terminal (OUT) while a hold signal higher than the threshold voltage (e.g., 5V) is input. there is. Accordingly, the control unit 133 and the watchdog timer 134 may operate using the driving voltage for a reference time from when the shutdown signal was last applied to the first communication terminal (COM1).

The trigger terminal (TRIG) selectively outputs a valid trigger signal or an invalid trigger signal. The valid trigger signal is for the control unit 133 to inform the watchdog timer 134 that it is operating. That is, the watchdog timer 134 can process that the control unit 133 is operating when a valid trigger signal is output through the trigger terminal (TRIG). As described above, the invalid trigger signal is for informing the watchdog timer 134 that the control unit 133 should end the operation, and the watchdog timer 134 sends a reset signal ( (e.g., 0V) is induced to be output.

The control unit 133 may output a valid trigger signal on the trigger terminal (TRIG) until a shutdown signal is input on the first communication terminal (COM1). On the other hand, when a shutdown signal is applied to the first communication terminal (COM1), the control unit 133 may output an invalid trigger signal to the trigger terminal (TRIG).

The reset terminal (RES) receives a reset signal from the watchdog timer 134. The control unit 133 is reset in response to a reset signal from the watchdog timer 134 input through the reset terminal RES. The reset signal may be a signal that induces the control unit 133 to stop outputting the hold signal so that the operating state of the power switch 132 is changed to the turn-off state.

Accordingly, the control unit 133 stops outputting the hold signal in response to the reset signal from the watchdog timer 134 input through the reset terminal (RES), determines whether to apply the driving voltage, and inputs the shutdown signal. Based on this, it is possible to diagnose whether the power switch 132 is malfunctioning.

Specifically, the control unit 133 may diagnose that a failure has occurred in the power switch 132 when the driving voltage is input after a reset signal is input and the output of the hold signal is stopped after the shutdown signal is input.

In other words, the control unit 133 stops outputting the hold signal that maintains the operating state of the power switch 132 in the turn-on state to block the driving voltage in response to the input of the shutdown signal, but when the driving voltage is input, It can be diagnosed that a failure has occurred in the power switch 132.

At this time, a failure of the power switch 132 may mean a failure that maintains the turn-on state even though the control unit 133 controls the operation state of the power switch 132 to be changed to the turn-off state.

According to the present invention, when a shutdown signal is input from the external device 1, the control unit 133 does not immediately block the input voltage applied to the DC-DC voltage converter 131, but maintains the input voltage in the applied state. By diagnosing whether a malfunction has occurred in the power switch 132, it is possible to quickly check whether a malfunction has occurred in the power switch 132 when operating in the next wake-up mode.

The second communication terminal COM2 outputs diagnostic data to the external device 1. When a wake-up signal commanding wake-up is input to the first communication terminal (COM1) through the communication unit 120, the control unit 133 detects a malfunction in the power switch 132 before the wake-up signal is input. Diagnostic data indicating the diagnosis result of whether or not the device has been diagnosed can be output on the second communication terminal (COM2). Diagnostic data output through the second communication terminal COM2 is converted into a notification signal in a form recognizable by the external device 1 by the second photo relay 122.

In other words, when a shutdown signal is input, the control unit 133 diagnoses whether a malfunction has occurred in the power switch 132 through the above-described process, and when a wake-up signal is input, the power switch 133 performs a power switch operation prior to input of the wake-up signal. Outputs diagnostic data indicating the diagnosis result of failure of (132).

The control unit 133 may further include sensing terminals S1, S2, and S3 for receiving a sensing signal from the sensing unit 110.

The watchdog timer 134 operates using the driving power supplied from the DC-DC voltage converter 131. The watchdog timer 134 repeatedly monitors that the battery management device 100 should terminate its operation. If the battery management device 100 monitors that the operation must end, the watchdog timer 134 may reset the battery management device 100. Resetting the battery management device 100 may mean resetting the control unit 133.

The watchdog timer 134 does not output a reset signal while a valid trigger signal is output through the trigger terminal (TRIG). On the other hand, the watchdog timer 134 outputs a reset signal when an invalid trigger signal is output.

Meanwhile, the control unit 133' according to another embodiment may diagnose whether a failure has occurred in the watchdog timer 134.

The control unit 133' determines whether the watchdog timer 134 is broken based on whether a reset signal is input to the reset terminal (RES) within a predetermined threshold time from the time an invalid trigger signal is output from the trigger terminal (TRIG). Diagnose.

Specifically, when a shutdown signal is input from the external device 1 to the first communication terminal COM1, the control unit 133' outputs an invalid trigger signal to the trigger terminal TRIG. At this time, the control unit 133' measures the elapsed time from when the invalid trigger signal is output.

Thereafter, the control unit 133' diagnoses that a failure has occurred in the watchdog timer 134 if the reset signal is not input within a predetermined threshold time from the time the invalid trigger signal is output. That is, the control unit 133' diagnoses that a failure has occurred in the watchdog timer 134 when the elapsed time exceeds a predetermined threshold time.

Conversely, the control unit 133' diagnoses that a failure has not occurred in the watchdog timer 134 when a reset signal is input within a predetermined threshold time from when the invalid trigger signal is output. That is, the control unit 133' diagnoses that a failure has not occurred in the watchdog timer 134 if the elapsed time is less than a predetermined threshold time.

When a wake-up signal commanding wake-up is input to the first communication terminal (COM1) through the communication unit 120, the control unit 133' malfunctions the watchdog timer 134 before the wake-up signal is input. Diagnostic data indicating the diagnosis result of whether this has occurred can be output on the second communication terminal (COM2). Diagnostic data output through the second communication terminal COM2 is converted into a notification signal in a form recognizable by the external device 1 by the second photo relay 122.

In other words, when a shutdown signal is input, the control unit 133' diagnoses whether a failure has occurred in the watchdog timer 134 through the above-described process, and when a wake-up signal is input, the control unit 133' performs the function performed before input of the wake-up signal. Diagnostic data indicating the diagnosis result of whether the watchdog timer 134 is malfunctioned is output.

Figure 3 is a flowchart showing a power switch diagnosis method according to another embodiment of the present invention. Before the method according to FIG. 3 is started, it is assumed that the control unit 133 is operating normally in wake-up mode.

1 to 3, in step 300, the control unit 133 determines whether a shutdown signal commanding the control unit 133 to shut down is input on the first communication terminal COM1. If the result of step 300 is “YES,” the process proceeds to step 310.

In step 310, the control unit 133 outputs a hold signal on the hold terminal (HOLD) to maintain the operating state of the power switch 132 in the turn-on state so that the input voltage is applied to the DC-DC voltage converter 131. do. Accordingly, the DC-DC voltage converter 131 outputs a driving voltage to the control unit 133 and the watchdog timer 134 using the input voltage while the hold signal is output.

In step 320, the control unit 133 outputs an invalid signal on the trigger terminal (TRIG) while a hold signal is output on the hold terminal (HOLD) (i.e., while a driving voltage is provided to the watchdog timer 134). Outputs a trigger signal. The invalid trigger signal is a signal that induces the watchdog timer 134 to input a reset signal to the reset terminal (RES).

In step 330, the watchdog timer 134 outputs a reset signal to the control unit 133 in response to the input of an invalid trigger signal.

In step 340, the control unit 133 stops outputting the hold signal when the reset signal is input. The power switch 132 in which a failure has not occurred changes its operating state to the turn-off state in response to the interruption of output of the hold signal. Accordingly, the DC-DC voltage converter 131 does not receive the input voltage and cannot output a driving voltage, and the control unit 133 enters a shutdown mode. The shutdown mode is a mode for blocking power consumption by the battery management device 100. That is, in the shutdown mode, the operation of the power switch diagnostic device 130 as well as the sensing unit 110 and the communication unit 120 is stopped.

Conversely, the malfunctioning power switch 132 maintains the turn-on state without changing its operating state to the turn-off state even though the output of the hold signal is stopped. Accordingly, the DC-DC voltage converter 131 receives the input voltage and outputs a driving voltage, and the control unit 133 receives the driving voltage and is driven.

In step 350, the control unit 133 diagnoses whether a failure has occurred in the power switch 132 based on whether a driving voltage is applied and whether a shutdown signal is input. As described above, the faulty power switch 132 remains turned on even though the output of the hold signal is stopped, so a driving voltage is applied to the control unit 133.

Accordingly, the control unit 133 may diagnose that a failure has occurred in the power switch 132 if there is a history of inputting a shutdown signal before the reset signal is input, and the driving voltage is applied after receiving the reset signal.

In step 360, the control unit 133 stores diagnostic data indicating the diagnosis result of the power switch 132 in memory.

In step 370, the control unit 133 determines whether a wake-up signal commanding wake-up of the control unit 133 is applied to the first communication terminal COM1. If the result of step 360 is “YES,” step S370 proceeds.

In step 380, the control unit 133 enters the wake-up mode and outputs the diagnostic data stored in the memory on the second communication terminal (COM2). Accordingly, it is possible to notify the external device 1 whether a failure has occurred in the power switch 132.

Figures 4 and 5 are timing charts showing the operation of a standard watchdog timer that can be used as the watchdog timer of Figure 2.

The standard watchdog timer is cleared in response to a trigger pulse generated within a predetermined timeout period, and outputs a reset signal if the trigger pulse is not received within the timeout period.

Referring to FIG. 4, the control unit 133 operating normally in wake-up mode may output a valid trigger signal 400 on the trigger terminal (TRIG). The valid trigger signal 400 may include trigger pulses 401, 402, and 403 having a predetermined high level voltage (eg, 3V). At this time, the time interval between two adjacent trigger pulses (eg, 402 and 403) included in the valid trigger signal is shorter than the timeout period of the standard watchdog timer, thereby preventing timeout of the standard watchdog timer. The standard watchdog timer prevents the control unit 133 from being reset by outputting a predetermined high level voltage (e.g., 5V) on the reset terminal (RES) of the control unit 133 while a timeout does not occur. You can.

On the other hand, referring to FIG. 5, due to a malfunction of the control unit 133, a so-called 'late fault' may occur in which the trigger pulse from the control unit 133 is interrupted for longer than the timeout period. For example, when a slow failure of the control unit 133 occurs, such as missing the trigger pulse 503 in FIG. 5, the standard watchdog timer sends a reset signal (e.g., 0V) is output.

FIG. 6 is a timing chart showing the operation of a window watchdog timer that can be used as the watchdog timer of FIG. 2.

The Windows Watchdog Timer, like the standard Watchdog Timer, can detect the occurrence of the aforementioned slow failures. Furthermore, the Windows watchdog timer can be said to be an improved watchdog timer than the standard watchdog timer in that it can also detect so-called 'fast faults'.

Referring to FIG. 6, the window watchdog timer can detect the time interval between trigger pulses 601, 602, 603, 604, and 605 sequentially output by the control unit 133. As shown, the fact that the time interval ΔT between the trigger pulse 602 and the trigger pulse 603 is shorter than the minimum time interval ΔT _TH predetermined for the window watchdog timer means that a rapid failure of the control unit 133 has occurred. can do. The window watchdog timer outputs a reset signal (eg, 0V) on the reset terminal (RES) of the control unit 133 when a rapid failure of the control unit 133 occurs. The above-described invalid trigger signal may be a signal including at least two trigger pulses, such as the trigger pulse 602 and the trigger pulse 603, where the time interval ΔT between them is shorter than the minimum time interval ΔT _TH .

On the other hand, in case of a slow failure of the control unit 133 in which no trigger pulse is generated during the timeout period from the end of the previous trigger pulse 604 due to the disappearance of the trigger pulse 605, etc., the window watchdog timer Outputs a reset signal (eg, 0V) on the reset terminal (RES) of the control unit 133.

The embodiments of the present invention described above are not only implemented through devices and methods, but may also be implemented through a program that realizes the function corresponding to the configuration of the embodiment of the present invention or a recording medium on which the program is recorded. The implementation can be easily implemented by an expert in the technical field to which the present invention belongs based on the description of the embodiments described above.

Although the present invention has been described above with limited examples and drawings, the present invention is not limited thereto, and the technical idea of the present invention and the description below will be understood by those skilled in the art to which the present invention pertains. Of course, various modifications and variations are possible within the scope of equivalence of the patent claims.

In addition, the present invention described above is capable of various substitutions, modifications and changes without departing from the technical spirit of the present invention to those of ordinary skill in the technical field to which the present invention pertains. It is not limited by the drawings, and all or part of each embodiment can be selectively combined so that various modifications can be made.

The embodiments of the present invention described above are not only implemented through devices and methods, but may also be implemented through a program that realizes the function corresponding to the configuration of the embodiment of the present invention or a recording medium on which the program is recorded. The implementation can be easily implemented by an expert in the technical field to which the present invention belongs based on the description of the embodiments described above.

Although the present invention has been described above with limited examples and drawings, the present invention is not limited thereto, and the technical idea of the present invention and the description below will be understood by those skilled in the art to which the present invention pertains. Of course, various modifications and variations are possible within the scope of equivalence of the patent claims.

In addition, the present invention described above is capable of various substitutions, modifications and changes without departing from the technical spirit of the present invention to those of ordinary skill in the technical field to which the present invention pertains. It is not limited by the drawings, and all or part of each embodiment can be selectively combined so that various modifications can be made.

10: Battery pack
20: Battery module
30: contactor
100: Battery management device
110: Sensing unit
120: Department of Communications
130: Power switch diagnostic device
131: DC-DC voltage converter
132: power switch
133: Control unit
134: Watchdog Timer

Claims (10)

A DC-DC voltage converter configured to output a driving voltage using an input voltage;
a power switch that applies or blocks the input voltage to the DC-DC voltage converter;
a watchdog timer driven by applying the driving voltage; and
It includes a power input terminal, a first communication terminal, a hold terminal, a trigger terminal, and a reset terminal, and is driven by applying the driving voltage to the power input terminal, and a shutdown signal commanding shutdown is input to the first communication terminal. In this case, outputting a hold signal that induces the operating state of the power switch to remain in the turn-on state to the power switch through the hold terminal, and inducing the watchdog timer to output a reset signal on the reset terminal. It includes a control unit that outputs a valid trigger signal to the watchdog timer through the trigger terminal,
When the invalid trigger signal is input, the watchdog timer outputs the reset signal to the reset terminal to induce the control unit to stop outputting the hold signal so that the operating state of the power switch is changed to a turn-off state. do,
The control unit
When the reset signal from the watchdog timer is input to the reset terminal, stop outputting the hold signal,
A power switch diagnostic device that diagnoses that a failure has occurred in the power switch when the driving voltage is input to the power input terminal even after stopping the output of the hold signal. delete According to paragraph 1,
The control unit
A power switch diagnostic device that outputs diagnostic data indicating a diagnosis result of whether the power switch is malfunctioning when a wakeup signal commanding wakeup is input.
According to paragraph 1,
The control unit
A power switch diagnostic device that diagnoses whether the watchdog timer is broken based on whether the reset signal is input within a predetermined threshold time from when the invalid trigger signal is output.
According to paragraph 4,
The control unit
A power switch diagnostic device that diagnoses that a failure has occurred in the watchdog timer when the reset signal is not input within a predetermined threshold time from when the invalid trigger signal is output.
According to paragraph 4,
The control unit
A power switch diagnostic device that outputs diagnostic data indicating a diagnosis result of a failure of the watchdog timer when a wakeup signal commanding wakeup is input.
A battery management device comprising the power switch diagnostic device according to any one of claims 1 and 3 to 6. A battery pack including the power switch diagnostic device according to any one of claims 1 and 3 to 6. A DC-DC voltage converter configured to output a driving voltage using an input voltage; a power switch that applies or blocks the input voltage to the DC-DC voltage converter; a control unit including a power input terminal, a first communication terminal, a hold terminal, a trigger terminal, and a reset terminal, and being driven by applying the driving voltage to the power input terminal; In the power switch diagnosis method of diagnosing whether the power switch is broken using a power switch diagnosis device including a watchdog timer driven by applying the driving voltage,
When a shutdown signal commanding shutdown is input to the first communication terminal, the control unit outputs a hold signal to the power switch through the hold terminal to induce the operation state of the power switch to remain in the turn-on state, outputting an invalid trigger signal through the trigger terminal to induce the watchdog timer to output a reset signal on the reset terminal;
When the invalid trigger signal is input through the trigger terminal, the watchdog timer generates the reset signal that induces the control unit to stop outputting the hold signal so that the operating state of the power switch is changed to a turn-off state. outputting output to the reset terminal;
When the reset signal from the watchdog timer is input to the reset terminal, the control unit stops outputting the hold signal; and
If the driving voltage is input to the power input terminal even after stopping the output of the hold signal, the control unit diagnosing that a failure has occurred in the power switch;
Including power switch diagnostic method. delete

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