Patent Description:
Among them, the lithium batteries are in the limelight since they have almost no memory effect compared to nickel-based batteries and also have very low self-discharging rate and high energy density.

Meanwhile, a battery pack having a battery may include a capacitor for smoothing the DC power output from the battery. That is, the capacitor is a DC link capacitor or a smoothing capacitor and may smooth the DC power to a certain level.

However, since the smoothing capacitor frequently fails due to degradation, it is important to accurately diagnose a state of the smoothing capacitor.

Conventionally, there has been disclosed a technique for controlling a DC power supplied from a power supplier to a motor to a certain magnitude, estimating a rate of change of the DC link capacitance in consideration of a power consumed by a resistor of the motor, a power consumed by the power supplier and a switching loss power of the inverter when the DC link voltage reaches a predetermined voltage, and diagnosing the degree of degradation of the DC link capacitor using the rate of change of the DC link capacitance (Patent Literature <NUM>).

However, in Patent Literature <NUM>, the DC link capacitor is discharged through the motor to measure the capacitance. For this, the motor must be stopped, and the system must also be stopped to cut off the power to the inverter, so it is difficult to frequently measure the degradation of the capacitor. In addition, if the motor is replaced with another motor after measuring an initial value of the capacitance, the power consumed by a load is changed, so an error may occur.

Further background art is described in <CIT>, <CIT>, <CIT> and <CIT>.

The present disclosure is designed to solve the problems of the related art, and therefore the present disclosure is directed to providing a battery management apparatus, which diagnosing a state of a capacitor provided in a control unit by applying an AC current.

In one aspect of the present disclosure, there is provided a battery management apparatus, comprising: an inverter connected to a battery cell and configured to convert a DC current output from the battery cell into an AC current according to an operation state of a plurality of switches provided therein; a measuring unit connected to a diagnosis line at which the AC current converted by the inverter is output, the measuring unit being configured to measure a voltage of the diagnosis line and output the measurement result; and a control unit having a plurality of capacitors connected to the diagnosis line and configured to control the operation state of the plurality of switches, receive the measurement result output from the measuring unit and diagnose a state of the plurality of capacitors based on the received measurement result.

The inverter may include a first unit circuit connected to the battery cell and configured so that the plurality of switches and a plurality of primary coils are arranged in series therein; and a second unit circuit connected to the diagnosis line and configured so that a secondary coil corresponding to the plurality of primary coils is disposed therein.

The plurality of switches may include a first switch and a second switch.

The control unit may be configured to alternately control the operation states of the first switch and the second switch according to a predetermined cycle.

When receiving a measurement command from the control unit, the measuring unit may measure voltages at both ends of a shunt resistor provided on the diagnosis line and calculate a difference between the measured both-end voltages.

The control unit may include a third switch formed to select a capacitor to be connected to the diagnosis line among the plurality of capacitors according to an operation state thereof, and the control unit may be configured to diagnose a state of each of the plurality of capacitors by controlling the operation state of the third switch.

The control unit may be configured to control the operation state of the third switch, when the received measurement result is different from a reference value over a predetermined level.

The control unit may be configured to control the operation state of the third switch so that a predetermined capacitor among the plurality of capacitors is connected to the diagnosis line, then control the operation state of the plurality of switches so that the AC current is output, and diagnose a state of the predetermined capacitor based on a re-measurement result received from the measuring unit.

The battery cell may be provided in plural.

The battery management apparatus according to another aspect of the present disclosure may further comprise a cell selection unit connected between the plurality of battery cells and the inverter and configured to select a battery cell to be connected to the inverter among the plurality of battery cells according to a cell selection command received from the control unit.

The control unit may include a plurality of slave control units respectively having the plurality of capacitors; and a master control unit connected to the plurality of slave control units and configured to send the cell selection command to the cell selection unit.

The battery management apparatus according to another aspect of the present disclosure may further comprise a slave selection unit connected between the inverter and the plurality of slave control units and configured to select a slave control unit to be connected to the inverter through the diagnosis line among the plurality of slave control units according to a slave selection command received from the master control unit.

The battery cell may be provided in plural, and the inverter may be provided in plural to respectively correspond to the plurality of battery cells.

The control unit may include a plurality of slave control units respectively corresponding to the plurality of inverters and configured to respectively have the plurality of capacitors; and a master control unit connected to the plurality of slave control units and configured to designate a slave control unit, which diagnoses a state of the plurality of capacitors provided therein, among the plurality of slave control units.

A battery management system (BMS) according to still another aspect of the present disclosure may comprise the battery management apparatus according to the present disclosure.

A battery pack according to still another aspect of the present disclosure may comprise the battery management apparatus according to the present disclosure.

According to an aspect of the present disclosure, even if a special measuring device is not provided, there is an advantage that the state of a capacitor provided inside the control unit may be diagnosed.

In addition, according to an aspect of the present disclosure, since the battery cell that outputs a current and the capacitor to be diagnosed can be selected through a simple circuit configuration inside the battery pack, the manufacturing time and cost of the battery pack may be reduced.

In addition, according to an aspect of the present disclosure, since a plurality of capacitors are provided inside the control unit, it is possible to effectively prevent loss of a signal input to the control unit.

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

Furthermore, the term "control unit" described in the specification refers to a unit that processes at least one function or operation, and may be implemented by hardware, software, or a combination of hardware and software.

Hereinafter, a preferred embodiment of the present disclosure will be described in detail with reference to the accompanying drawings.

<FIG> is a diagram schematically showing a battery pack <NUM> including a battery management apparatus <NUM> according to an embodiment of the present disclosure, and <FIG> is a diagram showing an exemplary configuration of the battery pack <NUM> including the battery management apparatus <NUM> according to an embodiment of the present disclosure.

Referring to <FIG>, the battery pack <NUM> may include a battery cell <NUM> and a battery management apparatus <NUM>. Here, the battery cell <NUM> refers to one independent cell that has a negative electrode terminal and a positive electrode terminal and is physically separable. For example, one pouch-type lithium polymer cell may be regarded as the battery cell <NUM>.

The battery management apparatus <NUM> may include an inverter <NUM>, a measuring unit <NUM> and a control unit <NUM>.

The inverter <NUM> is connected to the battery cell <NUM> and may be configured to convert a DC current output from the battery cell <NUM> into an AC current according to an operation state of a plurality of switches included therein so as to output the AC current.

For example, the inverter <NUM> may be a DC-AC inverter <NUM> that converts a DC current output from the battery cell <NUM> into an AC current.

Specifically, the inverter <NUM> may include a plurality of input terminals and a plurality of output terminals. The inverter <NUM> may be connected to the battery cell <NUM> through a line that is connected to the plurality of input terminals. In addition, an AC current may be output through the line connected to the plurality of output terminals.

For example, referring to <FIG>, the inverter <NUM> may be connected to the positive electrode terminal of the battery cell <NUM> through a first line L1 connected to a first input terminal i1 and be connected to the negative electrode terminal of the battery cell <NUM> through a second line L2 connected to a second input terminal i2. In addition, the AC current converted by the inverter <NUM> may be output through a first diagnosis line DL1 connected to a first output terminal O1 of the inverter <NUM> and a second diagnosis line DL2 connected to a second output terminal <NUM>.

The measuring unit <NUM> may be configured to be connected to a diagnosis line at which the AC current converted by the inverter <NUM> is output.

In addition, the measuring unit <NUM> may be configured to measure a voltage of the diagnosis line and output a measurement result. For example, the measuring unit <NUM> may measure voltages of both ends of a predetermined element arranged on the diagnosis line and output the measured result.

The control unit <NUM> may be configured to include a plurality of capacitors connected to the diagnosis line.

Specifically, a plurality of capacitors may be disposed at an input terminal of the control unit <NUM> to which voltage is input. Here, the plurality of capacitors may be connected in series with each other. That is, the plurality of capacitors may be configured to smooth the input voltage by removing noise included in the voltage input to the control unit <NUM>.

For example, referring to <FIG>, a first capacitor C1 and a second capacitor C2 may be provided inside the control unit <NUM>. One end of the first capacitor C1 may be connected to the first diagnosis line DL1, and the other end may be connected to one end of the second capacitor C2. The other end of the second capacitor C2 may be connected to the second diagnosis line DL2. However, it should be noted that in the embodiment of <FIG>, only the diagnosis line is connected to the first capacitor C1 and the second capacitor C2 in order to diagnose the state of the first capacitor C1 and the second capacitor C2. That is, the first capacitor C1 and the second capacitor C2 may be connected to any line without limitation a long as the line is connected to the input terminal of the control unit <NUM> to apply a voltage to the control unit <NUM> at the inside or outside of the battery pack <NUM> as well as the diagnosis line, and may smooth the input voltage.

In addition, since a plurality of capacitors are provided inside the control unit <NUM>, the voltage input to the control unit <NUM> may be stabilized even if any one of the plurality of capacitors is not in a normal state. Therefore, the control unit <NUM> may receive a stable voltage through the plurality of capacitors.

The control unit <NUM> may be configured to control the operation state of the plurality of switches.

Specifically, the control unit <NUM> may be connected to each of the plurality of switches provided in the inverter <NUM>, and transmit a control command to each of the plurality of switches through the connected line. In this case, the operation state of the switch receiving the control command from the control unit <NUM> may be controlled to a turn-on state or a turn-off state.

The control unit <NUM> may be configured to receive the measurement result output from the measuring unit <NUM>.

Preferably, the control unit <NUM> and the measuring unit <NUM> may be connected by wire. In addition, the control unit <NUM> may receive the measurement result measured by the measuring unit <NUM> through a connected line.

For example, in the embodiment of <FIG>, the control unit <NUM> may be configured to receive the measurement result, obtained by measuring the voltage of the diagnosis line by the measuring unit <NUM>, through the line connected to the measuring unit <NUM>.

The control unit <NUM> may be configured to diagnose the state of the plurality of capacitors based on the received measurement result.

Specifically, the measuring unit <NUM> may convert the measurement result into a digital signal and send the converted digital signal to the control unit <NUM>. The control unit <NUM> may receive the converted digital signal from the measuring unit <NUM> and the measurement result measured by the measuring unit <NUM> by reading the converted digital signal. In addition, the control unit <NUM> may diagnose whether the state of the plurality of capacitors is normal based on the obtained measurement result.

The battery management apparatus <NUM> according to an embodiment of the present disclosure has an advantage of diagnosing the state of a capacitor provided in the control unit <NUM> even if a special measuring device is not provided. In addition, the battery management apparatus <NUM> has an advantage of more effectively stabilizing the voltage applied to the control unit <NUM> by using a plurality of capacitors.

<FIG> is a diagram showing an exemplary configuration of the inverter <NUM> according to an embodiment of the present disclosure.

Referring to <FIG>, the inverter <NUM> may be configured to include a first unit circuit <NUM> and a second unit circuit <NUM>. For example, as shown in <FIG>, the first unit circuit <NUM> and the second unit circuit <NUM> may be formed to be physically separated.

The first unit circuit <NUM> may be formed so that the battery cell <NUM> is connected thereto.

Specifically, the first unit circuit <NUM> may be connected to the first input terminal i1 of the inverter <NUM>, and the first line L1 connected to the positive electrode terminal of the battery cell <NUM> may be connected to the first input terminal i1 of the inverter <NUM>. In addition, the first unit circuit <NUM> may be connected to the second input terminal i2 of the inverter <NUM>, and the second line L2 connected to the negative electrode terminal of the battery cell <NUM> may be connected to the second input terminal i2 of the inverter <NUM>. Therefore, the first unit circuit <NUM> may be connected to the first line L1 and the second line L2 through the first input terminal i1 and the second input terminal i2 of the inverter <NUM>. As a result, the first unit circuit <NUM> may be connected to the battery cell <NUM>.

The first unit circuit <NUM> may be configured such that the plurality of switches and a plurality of primary coils are arranged in series therein.

That is, the plurality of switches and the plurality of primary coils may form one closed circuit. In addition, the plurality of primary coils may be wound in the same direction.

Specifically, referring to <FIG>, one end of the first switch SW1 may be connected to one end of the second switch SW2, and the other end may be connected to one end of the first primary coil PC1. In addition, the other end of the first primary coil PC1 may be connected to one end of the second primary coil PC2. The other end of the second primary coil PC2 may be connected to the other end of the second switch SW2.

In addition, a line connected between the other end of the first primary coil PC1 and one end of the second primary coil PC2 may be connected to the first input terminal i1 of the inverter <NUM>, and thus connected to the first line L1. That is, the line connected between the other end of the first primary coil PC1 and one end of the second primary coil PC2 may be connected to the positive electrode terminal of the battery cell <NUM>.

In addition, a line connected between one end of the second switch SW2 and one end of the first switch SW1 may be connected to the second input terminal i2 of the inverter <NUM>, and thus connected to the second line L2. That is, the line connected between one end of the first switch SW1 and one end of the second switch SW2 may be connected to the negative electrode terminal of the battery cell <NUM>.

Through such a circuit connection configuration, the first unit circuit <NUM> provided to the inverter <NUM> may be configured to be connected to the battery cell <NUM>.

The second unit circuit <NUM> may be configured to be connected to the diagnosis line.

Specifically, the second unit circuit <NUM> may be connected to the first output terminal O1 of the inverter <NUM>, and thus connected to the first diagnosis line DL1 connected to the first output terminal O1. In addition, the second unit circuit <NUM> may be connected to the second output terminal O2 of the inverter <NUM>, and thus connected to the second diagnosis line DL2 connected to the second output terminal O2 of the inverter <NUM>. Accordingly, the second unit circuit <NUM> may be connected to the first diagnosis line DL1 and the second diagnosis line DL2 through the first output terminal O1 and the second output terminal O2 of the inverter <NUM>. As a result, the second unit circuit <NUM> may be connected to the plurality of capacitors provided in the control unit <NUM>.

The second unit circuit <NUM> may include a secondary coil SC corresponding to the plurality of primary coils.

Referring to the embodiment of <FIG>, the plurality of primary coils and the secondary coil SC may be disposed to face each other.

Specifically, the secondary coil SC may be disposed in the second unit circuit <NUM> to face the plurality of primary coils so that an electromotive force may be induced by the plurality of primary coils. That is, if a current flows through the plurality of primary coils, an electromotive force may be induced in the secondary coil SC by a magnetic field generated in the primary coils.

Preferably, the length of the secondary coil SC disposed in the second unit circuit <NUM> may be formed longer than the length of the primary coil disposed in the first unit circuit <NUM>. For example, as shown in <FIG>, the length of both ends of the secondary coil SC arranged in the second unit circuit <NUM> may be longer than the length from the center of the first primary coil PC1 arranged in the first unit circuit <NUM> to the center of the second primary coil PC2.

Alternatively, preferably, the length of the secondary coil SC disposed in the second unit circuit <NUM> may be formed to be longer than the sum of the lengths of the plurality of primary coils disposed in the first unit circuit <NUM>. For example, the length of both ends of the secondary coil SC disposed in the second unit circuit <NUM> may be greater than or equal to the length from one end of the first primary coil PC1 disposed in the first unit circuit <NUM> to the other end of the second primary coil PC2.

Since the battery management apparatus <NUM> according to an embodiment of the present disclosure includes the inverter <NUM> having a simple circuit structure including a plurality of switches and a plurality of coils, the internal configuration of the battery pack <NUM> may be simplified, and there is an advantage that the DC current output from the battery cell <NUM> may be easily converted into an AC current.

Referring to the embodiment of <FIG>, the plurality of switches provided in the inverter <NUM> may include a first switch SW1 and a second switch SW2.

In addition, the control unit <NUM> may be configured to alternately control the operation states of the first switch SW1 and the second switch SW2 according to a predetermined cycle.

For example, if the state of the first switch SW1 is controlled to a turn-on state by the control unit <NUM>, the DC current output from the battery cell <NUM> may flow to the first primary coil PC1 and the first switch SW1. In this case, an induced electromotive force may be generated in the secondary coil SC by the magnetic field generated in the first primary coil PC1. In addition, the DC current may be output from the secondary coil SC toward the first diagnosis line DL1 by the generated induced electromotive force.

In addition, if the state of the first switch SW1 is controlled to a turn-off state by the control unit <NUM> and the state of the second switch SW2 is controlled to a turn-on state, the DC current output from the battery cell <NUM> may flow to the second primary coil PC2 and the second switch SW2. In this case, an induced electromotive force may be generated in the secondary coil SC by the magnetic field generated in the second primary coil PC2. In addition, the DC current may be output from the secondary coil SC toward the second diagnosis line DL2 by the generated induced electromotive force.

That is, since the first primary coil PC1 and the second primary coil PC2 are wound in the same direction, the current generated in the secondary coil SC may be output in different directions.

Accordingly, the control unit <NUM> may alternately control the operation states of the first switch SW1 and the second switch SW2 to a turn-on state and a turn-off state according to a predetermined cycle, so that the AC current is applied to the plurality of capacitors. Here, the predetermined cycle is a preset cycle, and may be a fixed value that is not changed according to the state of the battery pack <NUM> or the battery management apparatus <NUM> in order to accurately diagnose the state of the plurality of capacitors.

For example, one cycle may mean a time during which the operation state of the first switch SW1 is controlled from a turn-off state to a turn-on state and then comes to a turn-off state again and the operation state of the second switch SW2 is controlled from a turn-off state to a turn-on state from and then comes to a turn-off state again. That is, one cycle may mean a time when first switch SW1 is closed and opened once and then the second switch SW2 is closed and opened once. Accordingly, the control unit <NUM> may convert the DC current output from the battery cell <NUM> into an AC current by alternately controlling the states of the first switch SW1 and the second switch SW2 according to a predetermined cycle.

The battery management apparatus <NUM> according to an embodiment of the present disclosure has an advantage of converting a DC current to an AC current using an uncomplicated configuration by controlling the operation state of the plurality of switches, even if a separate AC power source is not provided.

If receiving a measurement command from the control unit <NUM>, the measuring unit <NUM> may be configured to measure voltages at both ends of a shunt resistor provided on the diagnosis line and calculate a difference between the measured both-end voltages.

The shunt resistor SR may be disposed on at least one of the first diagnosis line DL1 and the second diagnosis line DL2. Hereinafter, for convenience of explanation, it will be described that the shunt resistor SR is disposed on the first diagnosis line DL1. In addition, the resistance of the shunt resistor SR is a predetermined value, and may be stored in advance in the control unit <NUM> or in a memory that the control unit <NUM> may refer to.

The measuring unit <NUM> may receive the measurement command through a line connected to the control unit <NUM>. For example, the control unit <NUM> may send the measurement command to the measuring unit <NUM> while alternately controlling the operation states of the first switch SW1 and the second switch SW2. If receiving the measurement command from the control unit <NUM>, the measuring unit <NUM> may measure the voltage at one end of the shunt resistor SR and the voltage at the other end thereof.

In addition, the measuring unit <NUM> may calculate a voltage drop by the shunt resistor SR by obtaining the difference between the measured voltage at one end of the shunt resistor SR and the measured voltage at the other end thereof.

The control unit <NUM> may include a third switch SW3 formed to select a capacitor to be connected to the diagnosis line among the plurality of capacitors according to an operation state.

For example, the control unit <NUM> may include the third switch SW3 capable of connecting each of the plurality of capacitors to the diagnosis line, and may be configured to diagnose the state of each of the plurality of capacitors or the plurality of capacitors by controlling an operation state of the third switch SW3.

As another example, the control unit <NUM> may include the third switch SW3 configured simpler, and may be configured to diagnose the state of some of the plurality of capacitors or the plurality of capacitors by controlling the operation state of the third switch SW3. In this case, the control unit <NUM> may be configured to diagnose a state of the capacitor that is not connected to the diagnosis line by comparing the diagnosis result obtained by diagnosing the state of the plurality of capacitors with the diagnosis result obtained by diagnosing the state of some of the capacitors.

The third switch SW3 will be described in detail with reference to <FIG>.

<FIG> are diagrams showing an exemplary configuration of the control unit <NUM> according to an embodiment of the present disclosure.

Specifically, <FIG> is a diagram illustrating an example in which the conductor included in the third switch SW3 is not connected to both the first terminal t1 and the second terminal t2. <FIG> is a diagram illustrating an example in which the conductor included in the third switch SW3 is connected to the first terminal <NUM>. <FIG> is a diagram illustrating an example in which the conductor included in the third switch SW3 is connected to the second terminal t2. Here, the conductor included in the third switch SW3 may be an object with conductivity, for example a steel plate formed in a flat shape.

Referring to <FIG>, the control unit <NUM> may control the operation state of the third switch SW3 so that the conductor contacts the first terminal t1, thereby allowing both the first capacitor C1 and the second capacitor C2 to be connected to the diagnosis line.

Also, referring to <FIG>, the control unit <NUM> may control the operation state of the third switch SW3 so that the conductor contacts the second terminal t2, thereby allowing the first capacitor C1 to be connected to the diagnosis line.

In addition, the control unit <NUM> may be configured to diagnose the state of each of the plurality of capacitors by controlling the operation state of the third switch SW3.

For example, referring to <FIG>, the control unit <NUM> may control the conductor to come into contact with the first terminal t1, thereby diagnosing the states of the first capacitor C1 and the second capacitor C2 together.

As another example, referring to <FIG>, by controlling the conductor to contact the second terminal t2, the control unit <NUM> may diagnose the state of the first capacitor C1. In this case, the control unit <NUM> may determine the state of the second capacitor C2 by comparing the diagnosis result of the first capacitor C1 and the second capacitor C2 diagnosed in the embodiment of <FIG> with the diagnosis result of the first capacitor C1 diagnosed in the embodiment of <FIG>.

That is, as described above, the control unit <NUM> may connect some or all of the plurality of capacitors to the diagnosis line by controlling the operation state of the third switch SW3, in particular the conductor provided in the third switch SW3. In addition, the control unit <NUM> may diagnose the state of the capacitor connected to the diagnosis line by controlling the operation state of the plurality of switches provided in the inverter <NUM>.

Therefore, even if a diagnosis line is not provided to each of the plurality of capacitors, the battery management apparatus <NUM> according to an embodiment of the present disclosure has an advantage of conveniently diagnosing the state of each of the plurality of capacitors through a relatively simple configuration such as the third switch SW3.

The control unit <NUM> may be configured to control the operation state of the third switch SW3 when the received measurement result is different from a reference value over a predetermined level.

Here, the reference value may be set according to the number of capacitors connected to the diagnosis line. That is, the reference value may be a voltage drop by the shunt resistor SR, which is measured by the measuring unit <NUM> when one or more capacitors in a normal state are connected to the diagnosis line. Accordingly, the control unit <NUM> may diagnose the state of the capacitor provided therein when the reference value is different from the received measurement result over a predetermined level.

In addition, here, the predetermined level may be a predetermined margin section prepared for the case where a value measured by the measuring unit <NUM> is not accurate due to internal or external factors of the battery pack <NUM>.

For example, the predetermined level may be set to <NUM>% of the reference value. It is assumed that the reference value is <NUM> [uV]. If the plurality of capacitors are connected to the diagnosis line and the measurement result differs from the reference value by <NUM> [uV] or more, the control unit <NUM> may determine that the state of the plurality of capacitors connected to the diagnosis line is not a normal state.

Meanwhile, the voltage drop by the shunt resistor SR may be explained using Equation <NUM> below.

Here, Vd is the voltage drop by the shunt resistor SR, I is the current flowing through the shunt resistor SR, and Rsr is the resistance of the shunt resistor SR.

That is, the measuring unit <NUM> may measure the voltage drop (Vd) by the shunt resistor SR by measuring the both-end voltages of the shunt resistor SR and calculating the difference between the measured both-end voltages. In addition, the control unit <NUM> may receive the voltage drop (Vd) by the shunt resistor SR from the measuring unit <NUM>.

Here, the current (I) flowing through the shunt resistor SR may be explained using Equation <NUM> below.

Here, I is the current flowing through the shunt resistor SR, Vb is the voltage value of the battery cell <NUM>, and Xc is the reactance of the capacitor connected to the diagnosis line. Since the resistance of the shunt resistor SR is much smaller than the reactance of the capacitor, it does not affect the calculation of the current (I) flowing through the shunt resistor SR.

In other words, since the current (I) flowing through the shunt resistor SR is affected by the reactance (Xc) of the capacitor connected to the diagnosis line, the control unit <NUM> may diagnose the state of the capacitor provided inside based on the voltage drop by the shunt resistor SR measured by the measuring unit <NUM>.

If the battery management apparatus <NUM> according to an embodiment of the present disclosure is used, the states of the plurality of capacitors may be quickly and conveniently measured based on the voltage drop by the shunt resistor SR.

The control unit <NUM> may be configured to control the operation state of the third switch SW3 such that a predetermined capacitor among the plurality of capacitors is connected to the diagnosis line.

For example, as in the embodiment of <FIG>, the control unit <NUM> may control the operation state of the third switch SW3 so that the conductor contacts the second terminal t2, thereby allowing the first capacitor C1 to be connected to the diagnosis line.

Then, the control unit <NUM> may be configured to control the operation state of the plurality of switches so that the AC current is output. That is, the control unit <NUM> may control the operation state of the plurality of switches provided in the inverter <NUM> again in order to diagnose the state of the predetermined capacitor connected to the diagnosis line.

In addition, the control unit <NUM> may send a measurement command to the measuring unit <NUM>. After that, the control unit <NUM> may be configured to diagnose the state of the predetermined capacitor based on the re-measurement result received from the measuring unit <NUM>.

<FIG> is a diagram showing an exemplary configuration of a battery pack <NUM> including a battery management apparatus <NUM> according to another embodiment of the present disclosure.

Referring to <FIG>, a plurality of battery cells <NUM> may be provided in the battery pack <NUM>. For example, the battery pack <NUM> may include a battery module in which one or more battery cells <NUM> are connected in series and/or in parallel.

In addition, the battery management apparatus <NUM> may further include a cell selection unit <NUM> connected between the plurality of battery cells 10a, 10b, 10c and the inverter <NUM>. That is, the cell selection unit <NUM> may be connected between the battery module and the inverter <NUM>.

For example, in the embodiment of <FIG>, the cell selection unit <NUM> may be connected to the first battery cell 10a through a first sensing line SL1 and a second sensing line SL2, connected to the second battery cell 10b through the second sensing line SL2 and a third sensing line SL3, and connected to the third battery cell 10c through the third sensing line SL3 and a fourth sensing line SL4.

In addition, the cell selection unit <NUM> may be connected to the inverter <NUM> through the first line L1 and second line L2.

In addition, the cell selection unit <NUM> may be configured to select a battery cell <NUM> to be connected to the inverter <NUM> among the plurality of battery cells 10a, 10b, 10c according to a cell selection command received from the control unit <NUM>.

Therefore, even if the plurality of battery cells 10a, 10b, 10c are provided inside the battery pack <NUM>, the battery management apparatus <NUM> may further include the cell selection unit <NUM> capable of connecting each of the plurality of battery cells 10a, 10b, 10c to the inverter <NUM>. Therefore, since the battery management apparatus <NUM> may receive the current required for diagnosing a state of the capacitor from the battery cell <NUM> selected from the plurality of battery cells 10a, 10b, 10c, the state of the capacitor may be diagnosed based on the capacity state of the battery cell <NUM>.

<FIG> is a diagram showing an exemplary configuration of the battery pack <NUM> including the battery management <NUM> apparatus according to another embodiment of the present disclosure.

Referring to <FIG>, the control unit <NUM> may be configured to include a plurality of slave control units 131a, 131b, 131c, each including the plurality of capacitors; and a master control unit <NUM> connected to the plurality of slave control units 131a, 131b, 131c and sending the cell selection command to the cell selection unit <NUM>. Here, the master control unit <NUM> may be configured to control the plurality of slave control units 131a, 131b, 131c, respectively.

In addition, the battery management apparatus <NUM> may further include a slave selection unit <NUM> connected between the inverter <NUM> and the plurality of slave control units 131a, 131b, 131c.

For example, in the embodiment of <FIG>, the slave selection unit <NUM> may be connected to the first slave control unit 131a through a fifth sensing line SL5 and a sixth sensing line SL6, connected to the second slave control unit 131b through a seventh sensing line SL7 and an eighth sensing line SL8, and connected to the third slave control unit 131c through a ninth sensing line SL9 and a tenth sensing line SL10.

The slave selection unit <NUM> may be configured to select a slave control unit to be connected to the inverter <NUM> through the diagnosis line among the plurality of slave control units 131a, 131b, 131c according to the slave selection command received from the master control unit <NUM>. In addition, in the embodiment of <FIG>, the cell selection unit <NUM> may be configured to select a battery cell <NUM> to be connected to the inverter <NUM> among the plurality of battery cells 10a, 10b, 10c according to the cell selection command received from the master control unit <NUM>.

That is, the master control unit <NUM> may select a slave control unit capable of diagnosing the capacitor provided therein through the slave selection unit <NUM>, and select a battery cell <NUM> for supplying the DC current required for diagnosing the capacitor through the cell selection unit <NUM>.

Therefore, even if the plurality of battery cells 10a, 10b, 10c and the plurality of slave control units 131a, 131b, 131c are included in the battery pack <NUM>, the battery management apparatus <NUM> according to an embodiment of the present disclosure has an advantage of efficiently diagnosing the state of the plurality of capacitors C1, C2, C3, C4, C5, C6 provided in the plurality of slave control units 131a, 131b, 131c by using one inverter <NUM>.

Referring to <FIG>, a plurality of the battery cell <NUM> may be provided, and a plurality of the inverter <NUM> may be provided to correspond to the plurality of battery cells 10a, 10b, 10c, respectively.

That is, in the battery pack <NUM>, the same number of battery cells <NUM> and inverters <NUM> may be provided to correspond to each other one by one.

The control unit <NUM> may include a plurality of slave control units 131a, 131b, 131c configured to respectively correspond to the plurality of inverters 110a, 110b, 110c and respectively have the plurality of capacitors. That is, the battery cells <NUM>, the inverters <NUM> and the slave control units may be provided in the same number inside the battery pack <NUM>.

For example, in the embodiment of <FIG>, the first inverter 110a may include a first input terminal i1, a second input terminal i2, a first output terminal O1, and a second output terminal O2. In addition, the second inverter 110b may include a third input terminal i3, a fourth input terminal i4, a third output terminal O3, and a fourth output terminal O4. Also, the third inverter 110c may include a fifth input terminal i5, a sixth input terminal i6, a fifth output terminal O5, and a sixth output terminal O6.

In addition, the first line L1 may be connected to the first input terminal i1, and the second line L2 may be connected to the second input terminal i2 and the third input terminal i3. The third line L3 may be connected to the fourth input terminal i4 and the fifth input terminal i5, and the fourth line L4 may be connected to the sixth input terminal i6.

In addition, the control unit <NUM> may be configured to include a master control unit <NUM> connected to the plurality of slave control units 131a, 131b, 131c and configured to designate a slave control unit that diagnoses the state of the plurality of capacitors provided therein, among the plurality of slave control units 131a, 131b, 131c.

In this case, the master control unit <NUM> may be configured to control the operation state of the switch provided on the diagnosis line connected to the designated slave control unit to diagnose the state of the plurality of capacitors provided inside the designated slave control unit.

For example, in the embodiment of <FIG>, if the master control unit <NUM> designates the first slave control unit 131a, the master control unit <NUM> may control the operation state of the fourth switch SW4 provided on the diagnosis line connected to the first slave control unit 131a to a turn-on state. At this time, the operation state of a fifth switch SW5 and a sixth switch SW6 may be controlled to a turn-off state by the master control unit <NUM>.

The battery management apparatus <NUM> according to the present disclosure may be applied to a battery management system (BMS). That is, the BMS according to the present disclosure may include the battery management apparatus <NUM> described above. In this configuration, at least some components of the battery management apparatus <NUM> may be implemented by supplementing or adding functions of components included in the conventional BMS. For example, the inverter <NUM>, the measuring unit <NUM> and the control unit <NUM> may be implemented as components of the BMS.

In addition, the battery management apparatus <NUM> according to the present disclosure may be provided to a battery pack <NUM>. That is, the battery pack <NUM> according to the present disclosure may include the battery management apparatus <NUM> described above and one or more battery cells. In addition, the battery pack <NUM> may further include electrical equipment (a relay, a fuse, etc.) and a case.

The embodiments of the present disclosure described above may not be implemented only through an apparatus and method, but may be implemented through a program that realizes a function corresponding to the configuration of the embodiments of the present disclosure or a recording medium on which the program is recorded.

Claim 1:
A battery management apparatus (<NUM>), comprising:
an inverter (<NUM>) connected to a battery cell (<NUM>) and configured to convert a DC current output from the battery cell into an AC current according to an operation state of a plurality of switches (SW1, SW2) provided therein;
characterized in that it further comprises:
a measuring unit (<NUM>) connected to a diagnosis line (DL1, DL2) at which the AC current converted by the inverter is output, the measuring unit being configured to measure a voltage of the diagnosis line and output the measurement result; and
a control unit (<NUM>) having a plurality of capacitors (C1, C2) connected to the diagnosis line and configured to control the operation state of the plurality of switches, receive the measurement result output from the measuring unit and diagnose a state of the plurality of capacitors based on the received measurement result.