JP2017156297A - Voltage detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a voltage detector of a double flying capacitor system which can desirably detect a leakage failure of the flying capacitor, with simple configurations.SOLUTION: A voltage detector 10 includes: a flying capacitor Cholding the voltage of a first battery module; an operational amplifier OPmeasuring the voltage of the flying capacitor C; a flying capacitor Cholding the voltage of a second battery module; an operational amplifier OPmeasuring the voltage of the flying capacitor C; and a control unit 16. The control unit 16 calculates V-Vand V-Vfor each pair of the measurement value Vof the operational amplifier OPand the measurement value Vof the operational amplifier OP, and determines that the flying capacitor Chas a leakage failure if the relation of V-V≥a threshold value is satisfied for all the pairs and determines that the flying capacitor Chas a leakage failure if the relation of V-V≥the threshold value is satisfied for all the pairs.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a voltage detection device. In particular, the present invention relates to a voltage detector of a double flying capacitor type.

  A secondary battery (battery) is mounted on an electric vehicle such as an electric vehicle or a hybrid vehicle that obtains a vehicle driving force by a motor generator. The battery is configured by connecting battery module groups in series. The motor generator is driven by the electric power supplied from the battery. Further, when the motor generator functions as a generator, power from the motor generator is supplied to the battery, and the battery is charged.

  If the battery is overdischarged or overcharged, the battery performance may deteriorate. Therefore, it is necessary to control the charging or discharging by grasping the state of charge (SOC) of the battery. Therefore, it is necessary to detect the SOC of the battery with high accuracy, and for this purpose, it is necessary to accurately measure the voltage of the battery.

  A flying capacitor method is known as a battery voltage measurement method. In the flying capacitor system, both ends of the flying capacitor are connected to both ends of each battery module via an input-side relay, and both ends of the flying capacitor are connected to two input terminals of the differential amplifier via an output-side relay. A circuit is used.

  First, the input-side relay is closed (turned on), power from one battery module is supplied to the flying capacitor, and the voltage of the battery module is held in the flying capacitor. Next, the input side relay is opened (off), the output side relay is turned on, and the voltage held in the flying capacitor is supplied to the non-inverting input terminal and the inverting input terminal of the differential amplifier. By measuring the potential difference between the two input terminals with the differential amplifier, the terminal voltage of the flying capacitor, that is, the voltage of the battery module is measured. The above processing is sequentially performed on each battery module.

  In order to reduce the time required to measure the voltage of the battery, a double flying capacitor system having two sets of flying capacitors and differential amplifiers has been proposed (Patent Document 1). In the double flying capacitor method, the voltages of some battery modules are measured by the first differential amplifier, and the voltages of the remaining battery modules are measured by the second differential amplifier. According to the double flying capacitor method, the voltage of two battery modules can be measured simultaneously, so that the time required for measurement is reduced.

By the way, in order to accurately measure the voltage of the battery module, it is necessary that the voltage detection circuit is normal. For this reason, conventionally, a technique for determining an abnormality of a circuit for voltage detection has been proposed. For example, in Patent Document 2, in addition to a detection circuit (including a differential amplifier circuit, a sample hold circuit, and an AD converter) that detects the voltage of the battery module, a failure diagnosis circuit for determining an abnormality of the detection circuit is separately provided. A voltage detection apparatus is disclosed. The fault diagnosis circuit measures the voltage of the same battery module as that of the detection circuit, and when the measurement value of the fault diagnosis circuit reaches a preset reference voltage, the difference between the measurement value of the detection circuit and the reference voltage is calculated. Calculate. When the difference is equal to or greater than a predetermined value, it is determined that an abnormality has occurred in the detection circuit.

JP 2013-53939 A JP 2012-58135 A

  In the double flying capacitor type voltage detection device, a leakage may occur between both terminals of the flying capacitor due to a failure of the flying capacitor itself or a conductive foreign matter generated between both terminals of the flying capacitor. A failure that causes such a symptom is called a leak failure. When a leakage failure occurs in the flying capacitor, the voltage of each battery module is not suitably charged to the flying capacitor, and as a result, the voltage of the battery module is measured lower than the actual value.

  For example, as in the technique disclosed in Patent Document 2, a failure diagnosis circuit that determines abnormality of the detection circuit that detects the voltage of the battery module is separately provided, so that a leakage failure of the flying capacitor can be detected. However, when such a method is adopted, there is a problem that the circuit scale is increased by the amount of the fault diagnosis circuit, and the voltage detection device is enlarged and increased in cost. Further, in the technique disclosed in Patent Document 2, since the abnormality of the detection circuit is detected only when the voltage of the battery module becomes the reference voltage, when the battery module has a voltage other than the reference voltage, the detection circuit It can also point out the problem that no abnormalities are detected.

  An object of the present invention is to suitably detect a leakage failure of a flying capacitor with a simple configuration in a double flying capacitor type voltage detection device.

  The present invention is a voltage detection device that detects a voltage of a battery in which a plurality of first battery modules and a plurality of second battery modules are connected in series, and is a first flying to which power from each first battery module is supplied A capacitor, a first voltage measuring circuit for measuring a voltage of each first battery module by measuring a terminal voltage of the first flying capacitor, and a second flying capacitor to which power from each second battery module is supplied A second voltage measuring circuit for measuring a voltage of each second battery module by measuring a terminal voltage of the second flying capacitor, and a voltage obtained by measuring the voltage of each first battery module by the first voltage measuring circuit. A plurality of measured values and a plurality of measurements obtained by measuring the voltage of each second battery module by the second voltage measuring circuit. Based on a comparison between, characterized in that it and a leak failure detecting means for detecting either the leak failure of the first flying capacitor and the second flying capacitor.

  When the first flanking capacitor has a leakage failure, the voltage from the first battery module cannot be suitably held in the first flying capacitor. Therefore, each measured value by the first voltage measuring circuit is different from each value by the second voltage measuring circuit. Lower than the measured value. Similarly, when the second flanking capacitor has a leak failure, each measured value by the second voltage measuring circuit is lower than each measured value by the first voltage measuring circuit. Therefore, the leakage failure of either the first flying capacitor or the second flying capacitor can be detected by comparing each measurement value obtained by the first voltage measurement circuit with each measurement value obtained by the second voltage measurement circuit. it can.

  According to the above configuration, since it is not necessary to provide a separate failure diagnosis circuit or the like in order to detect a leakage failure of either the first flying capacitor or the second flying capacitor, the leakage failure of the flying capacitor is detected with a simple configuration. can do. Further, in the above configuration, there is no restriction that an abnormality is detected only when the voltage of the battery module becomes a specific voltage as in the technique described in Patent Document 2, for example, and a leakage failure of a flying capacitor is always performed. Can be detected.

  Preferably, the measurement value obtained by the first voltage measurement circuit and the second voltage measurement circuit are obtained for each set of the measurement value obtained by the first voltage measurement circuit and the measurement value obtained by the second voltage measurement circuit. The measured value is compared.

  Desirably, the difference between the measurement value obtained by one voltage measurement circuit of the first voltage measurement circuit and the second voltage measurement circuit and the measurement value obtained by the other voltage measurement circuit is a predetermined threshold value in all sets. When this is the case, a leakage failure of either the first flying capacitor or the second flying capacitor is detected.

  ADVANTAGE OF THE INVENTION According to this invention, in the voltage detection apparatus of a double flying capacitor system, the leakage failure of a flying capacitor can be detected suitably with a simple structure.

1 is a schematic configuration diagram of a voltage detection device according to an embodiment. It is a conceptual diagram which shows the leakage failure of a flying capacitor. Flying capacitor C _B is a diagram showing a voltage measurement value at the time of the leak failure. It is a figure which shows the voltage measurement value when abnormality arises in a battery module. It is a flowchart which shows the flow of a process of the voltage detection apparatus which concerns on this embodiment.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the drawings. FIG. 1 shows a schematic configuration diagram of a voltage detection apparatus 10 according to the present embodiment.

The battery 12 is obtained by connecting a plurality of battery modules B0 to B13 in series. One battery module is formed by connecting in series one or more (several (six) battery cells in this embodiment) battery cells. The voltage of each battery module is measured by an operational amplifier OP _A as a first voltage measurement circuit, which will be described later, or an operational amplifier OP _B as a second voltage measurement circuit. The plurality of battery modules B0 to B13 are conceptually classified into a first battery module whose voltage is measured by the operational amplifier OP _A and a second battery module whose voltage is measured by the operational amplifier OP _B. In the present embodiment, the first battery module includes battery modules B0, B1, B4, B5, B8, B9, B12, and B13, and the second battery module includes battery modules B2, B3, B6, and B7. , B10, and B11. The number of battery modules included in the battery 12 is not limited to the above.

One ends of input side relays IRY0 to IRY14 are connected to the battery modules B0 to B13, respectively. Specifically, one end of the input side relay IRYn is connected to the negative terminal of the battery module Bn (n = 0 or a positive integer), and the input side relay IRY (n + 1) is connected to the positive terminal of the battery module Bn. Are connected at one end. To explain some examples, one end of the input side relay IRY0 is connected to the negative terminal of the battery module B0, and one end of the input side relay IRY1 is connected to the positive terminal of the battery module B0 (also the negative terminal of the battery module B1). Connected. The other end of the input-side relay IRY0~IRY14 is connected to the flying capacitor _{C A} or flying capacitor _{C B.}

One terminal N0 of the flying capacitor _{C A} of the first flying capacitor is connected to the other end of the input-side relay IRY1, IRY5, IRY9, and IRY13. The other terminal N1 of the flying capacitor _{C A} is the input-side relay IRY0, IRY2, IRY4, IRY6, IRY8, IRY10, IRY12, and is connected to the other end of IRY14.

Since flying capacitor C _A is connected as described above, by opening and closing the respective input-side relay, power of each of the first battery module is supplied to the flying capacitor C _A. The flying capacitor C _A is charged, the voltage of the first battery module is held. For example, the input-side relay IRY0 and IRY1 is turned on, the power of the battery module B0 is supplied to the flying capacitor _{C A,} the voltage of the battery module B0 is held in the flying capacitor _{C A.}

In the present embodiment, the first flying capacitor is composed of one capacitor (flying capacitor C _A ), but the first flying capacitor may be composed of a plurality of capacitors connected in series.

One terminal N0 of the flying capacitor C _A is connected to one end of the output-side relay ORY0, the other terminal N1 of the flying capacitor C _A is connected to one end of the output-side relay ORY1.

The operational amplifier (operational amplifier) OP _A as the first voltage measurement circuit measures the terminal voltage of the flying capacitor C _A. The operational amplifier OP _A detects a potential difference between the two input terminals I0 and I1, amplifies the potential difference, and outputs the amplified potential difference. The input terminal I0 is connected to the other end of the output side relay ORY0, and the input terminal I1 is connected to the other end of the output side relay ORY1. Although this embodiment uses an operational amplifier OP _A as the first voltage measurement circuit, the first voltage measurement path may be measured if possible other constituting a terminal voltage of the flying capacitor C _A .

When the output-side relays ORY0 and ORY1 are turned on, one terminal N0 of the flying capacitor C _A is connected to the input terminal I0 of the operational amplifier OP _A , and the other terminal N1 of the flying capacitor C _A is connected to the input terminal I1 of the operational amplifier OP _A. Connected to. Thereby, the voltage held in the flying capacitor C _A is measured by the operational amplifier OP _A. The measured voltage is output to the A / D converter 14.

One terminal N1 of the flying capacitor _{C B} as a second flying capacitor is common and the other terminal of the flying capacitor _{C A,} as described above, the input-side relay IRY0, IRY2, IRY4, IRY6, IRY8, IRY10, Connected to the other ends of IRY12 and IRY14. The other terminal N2 of the flying capacitor _{C B} is connected to the other end of the input-side relay IRY3, IRY7, IRY11.

Since flying capacitor C _B is connected as described above, by opening and closing the respective input-side relay, power of each of the second battery module is supplied to the flying capacitor C _B. The flying capacitor C _B is charged, the voltage of the second battery module is held. For example, the input-side relay IRY2 and IRY3 is turned on, the power of the battery module B2 is supplied to the flying capacitor _{C B,} the voltage of the battery module B2 is held in the flying capacitor _{C B.}

In the present embodiment, the second flying capacitor is also composed of one capacitor (flying capacitor C _B ), but the second flying capacitor may also be composed of a plurality of capacitors connected in series.

As described above, one terminal N1 of the flying capacitor C _B that is common to the other terminal of the flying capacitor C _A is also connected to one end of the output-side relay ORY1, and the other terminal N2 of the flying capacitor C _B is It is also connected to one end of the output side relay ORY2.

The operational amplifier OP _B as the second voltage measurement circuit measures the terminal voltage of the flying capacitor C _B. The operational amplifier OP _B detects a potential difference between the two input terminals I1 and I2, amplifies the potential difference, and outputs the amplified potential difference. As described above, the input terminal I1 is connected to the other end of the output-side relay ORY1, and the input terminal I2 is connected to the other end of the output-side relay ORY2. In the present embodiment, the operational amplifier OP _B is used as the second voltage measurement circuit. However, the second voltage measurement path may have other configurations as long as the terminal voltage of the flying capacitor C _B can be measured. .

By the output-side relay ORY1 and ORY2 are turned on, the flying capacitor _C one terminal N1 of _B is connected to the input terminal I1 of the operational amplifier OP _B, the input terminal of the flying capacitor _C the other terminal N2 operational amplifier OP _B of _B I2 Connected to. Thereby, the voltage held in the flying capacitor C _B is measured by the operational amplifier OP _B. The measured voltage is output to the A / D converter 14.

The A / D converter 14 converts measured values of the operational amplifier OP _A and the operational amplifier OP _B from an analog signal to a digital signal and transmits the digital signal to the control unit 16.

  The control part 16 is comprised, for example from a microprocessor etc., and controls each part of the voltage detection apparatus 10 according to the program memorize | stored in the memory | storage part (not shown). For example, the control unit 16 performs control to open and close the input side relays IRY0 to IRY14 and the output side relays ORY0 to ORY2.

The control unit 16 also includes a plurality of measurement values V _A obtained by the operational amplifier OP _A measuring the voltages of the first battery modules, and a plurality of measurement values V _A obtained by the operational amplifier OP _B measuring the voltages of the second battery modules. Based on the comparison with the measured value V _B, it also functions as a leak failure detecting means for detecting a leak failure of either the flying capacitor C _A or the flying capacitor C _B. The function of the control unit 16 as leak failure detection means will be described later.

  The outline of the configuration of the voltage detection apparatus 10 is as described above. Since the voltage detection apparatus 10 is a double flying capacitor system as described above, the voltage of two battery modules can be measured simultaneously. In the voltage detection apparatus 10, the voltage of each battery module is measured according to the procedure described below.

Hereinafter, the function of the control unit 16 as the leak failure detection means will be described. First, a leak failure that may occur in the flying capacitor C _A and the flying capacitor C _B will be described. In FIG. 2, the flying capacitor C _A is shown to the leak failure.

If leak failure in the flying capacitor C _A occurs, as shown in FIG. 2 (a), cause the resistance component R _A between the terminals N0 and the terminal N1, toward the terminals N0 and the terminal N1, or from a terminal N1 _A current flows into the terminal N2 via the resistance component _RA . Thus, compared to when there is no leak failure, flying capacitor C _A is the voltage drops to hold.

When the first flying capacitor is composed of a plurality of capacitors, electric leakage may occur not only between the terminals N0 and N1, but also at the terminals between the capacitors. For example, as shown in FIG. 2B, when the first flying capacitor is composed of capacitors C _A1 and C _A2 , the leakage failure is caused by a leakage component between the terminal N 0 and the terminal N 1 due to the resistance component R _A , resistance 'leakage between (terminal between the capacitor _{C A1} and _{C A2),} and, terminal N1 by the resistance component _{R A2'} component _{R A1} terminals N0 and the terminal N1 by leakage between the terminals N1 may occur with. Even with these leak failures, the voltage held by the entire first flying capacitor is lowered.

  FIG. 2 shows a leak failure of the first flying capacitor, but a leak failure can occur in the same way for the second flying capacitor. According to the voltage detection apparatus 10 according to the present embodiment, any leak failure can be detected.

Hereinafter, a leakage failure detection method for the flying capacitor C _A and the flying capacitor C _B will be described.

3 shows, in the case where the leak failure in the flying capacitor C _B occurs is a graph representing the voltage measurement of each battery module B0～B13. In FIG. 3, the vertical axis represents the voltage value, and the letters B0 to B13 shown on the horizontal axis mean the battery modules B0 to B13, respectively. The letter A or B written under B0 to B13 indicates whether the voltage of the battery modules B0 to B13 is measured by the operational amplifier OP _A or the operational amplifier OP _B.

As shown in FIG. 3, the voltage values of the battery modules B2, B3, B6, B7, B10, and B11, that is, the second battery module measured by the operational amplifier OP _B are the battery modules B0, B1, B4, B5, B8, B9, B12, and B13, that is, the voltage value of the first battery module measured by the operational amplifier OP _A is lower.

If the battery modules included in the battery 12 are normal, they have substantially the same voltage. Therefore, if the battery modules are normal and their voltage values are measured correctly, the voltage measurement values of the battery modules should be approximately the same value. On the other hand, as described above, when a leakage failure occurs in the flying capacitor C _A or the flying capacitor C _B , all measured values measured by the operational amplifier connected to the flying capacitor in which the leakage failure has occurred are more than normal values. It will show a low value.

Accordingly, the control unit 16, a plurality of measurement values from the operational amplifier OP _A is obtained by measuring the voltage values of the first battery module (hereinafter, a measurement of the operational amplifier OP _A to as "measured value V _A") and , The operational amplifier OP _B compares a plurality of measurement values obtained by measuring the voltage values of the second battery modules (hereinafter, the measurement value of the operational amplifier OP _B is described as “measurement value V _B ”), It is possible to detect a leakage failure of the flying capacitor C _A and the flying capacitor C _B.

In the present embodiment, the comparison is performed on a plurality of sets including the measurement value V _A and the measurement value V _B. In the present embodiment, as shown in FIG. 3, the measurement values are compared in a plurality of sets P <b> 1 to P <b> 6 including the measurement value of the battery module Bm (m is an odd number) and the measurement value of the battery module B (m + 1). . In this embodiment, the measurement values of the battery modules adjacent in the series connection order are set as one set. However, the measurement values included in each set may be any as long as the measurement values V _A and the measurement values V _B are included. May be selected.

In the present embodiment, the difference between the measured value V _A and the measured value V _B , that is, V _A −V _B and V _B −V _A is calculated in each of the sets P1 to P6. At this time, for example, if the flying capacitor C _B has a leakage failure, all the measured values V _B are measured lower than the measured value V _A. Then, the control unit 16 determines that the set became V _A -V _B is equal to or larger than the threshold defined in advance when a predetermined number or more, the leakage fault occurs in the flying capacitor C _B. Further, it is determined that when the set became V _B -V _A is equal to or larger than the threshold a predetermined had more than a predetermined number, the leak failure in the flying capacitor C _A occurred.

The threshold value is set to a value that can detect a decrease in the voltage measurement value due to the leakage failure of the flying capacitor C _A or the flying capacitor C _B. Further, the predetermined number may be set as appropriate. For example, when V _A −V _B ≧ threshold in all the sets, it may be determined that the flying capacitor C _B has a leakage failure, or V _A -V _B ≧ threshold value becomes set of two or more there was flying when capacitor C _B may be determined to be leak failure.

In this embodiment, even when a failure (voltage drop) occurs simultaneously in a plurality (for example, two) of battery modules whose voltages are measured by the same operational amplifier, the failure of the battery module and the leakage failure of the flying capacitor as can cut, when it becomes the V _a -V _B ≧ threshold value in all the groups, determines that leak failure in the flying capacitor C _B occurs, becomes V _B -V _a ≧ threshold value in all the groups If, it determines the flying capacitor C _a leak failure occurs.

According to this, as shown in FIG. 4, for example, the battery modules B2 and B3 (both of which are voltage-measured by the operational amplifier OP _B ) are simultaneously failed, and their voltage values are considerably reduced. even when an, set to satisfy the V _a -V _B ≧ threshold is only set P1 and P2, it does not satisfy the condition that becomes V _a -V _B ≧ threshold value in all the groups. Therefore, in this case, the control unit 16 is not a leak failure of the flying capacitor C _B, may determine that a failure of the battery module B2 and B3.

In this embodiment, the comparison between the plurality of measurement values V _A and the plurality of measurement values V _B is performed by calculating the difference for each set of the measurement value V _A and the measurement value V _B. Other methods may be adopted. For example, compared representative values of a plurality of measured values V _A (for example, sums and averages) a representative value of the plurality of measurement values V _B, the flying capacitor C _A or flying capacitor C _B in accordance with the difference between the representative value A leak failure may be detected.

  Hereinafter, the flow of the leakage failure detection process of the flying capacitor in the voltage detection device 10 according to the present embodiment will be described with reference to the flowchart of FIG.

In step S10, the control unit 16 turns on only IRY1, IRY2, and IRY3 among the input side relays, and turns off the output side relays ORY0 to ORY2. This makes it possible to hold the voltage of the battery module B1 to flying capacitor C _A, thereby holding the voltage of the battery module B2 in the flying capacitor C _B. Thereafter, all the input side relays IRY0 to IRY14 are turned off, and the output side relays ORY0 to ORY2 are turned on. Thereby, the voltage held in the flying capacitor C _A (that is, the voltage of the battery module B1) is measured by the operational amplifier OP _A , and the voltage held in the flying capacitor C _B (that is, the voltage of the battery module B2) is measured by the operational amplifier OP _B. It is measured. It is assumed that the voltage of the battery module B0 has been measured.

In step S12, the control unit 16 calculates the difference in the set of the measurement value V _A and the measurement value V _B measured in step S10. Specifically, V _A −V _B and V _B −V _A are calculated. The control unit 16 temporarily stores the values of V _A −V _B and V _B −V _{A in} the storage unit.

In step S14, the control unit 16 determines whether or not voltage measurement of all battery modules has been completed. If not completed, the process returns to step S10 to measure the voltage of a battery module for which voltage measurement has not yet been performed. For example, in step S10 again, the control unit 16 turns on only IRY3, IRY4, and IRY5 among the input-side relays, and turns off the output-side relays ORY0 to ORY2. This makes it possible to hold the voltage of the battery module B3 to flying capacitor C _A, thereby holding the voltage of the battery module B4 in the flying capacitor C _B. Thereafter, all the input side relays IRY0 to IRY14 are turned off, and the output side relays ORY0 to ORY2 are turned on, and the voltages of the battery modules B3 and B4 are measured.

  If the processes from step S10 to step S14 are repeated and voltage measurement of all battery modules is completed, the process proceeds to step S16.

In step S16, the control unit 16 refers to the values of a plurality of V _A −V _B calculated in step S12 and temporarily stored in the storage unit, and whether V _A −V _B ≧ threshold is satisfied in all the sets. Determine whether or not. If satisfied, the process proceeds to step S18, in step S18, the control unit 16 determines that the leak failure has occurred in the flying capacitor C _B, the process ends.

If it is determined in step S16 that V _A −V _B ≧ threshold value is not satisfied in all the sets, the process proceeds to step S20.

In step S20, the control unit 16 refers to the values of a plurality of V _B −V _A calculated in step S12 and temporarily stored in the storage unit, and whether V _B −V _A ≧ threshold is satisfied in all sets. Determine whether or not. If satisfied, the process proceeds to step S22, in step S22, the control unit 16 determines that the leak failure has occurred in the flying capacitor C _A, the process ends.

_{If V} A -V _B ≧ threshold is determined not satisfied in all sets in step S20 the process proceeds to step S24, in step S24, the control unit 16 has occurred leak failure in the flying capacitor _{C A} and the flying capacitor _{C B} It is determined that there is not, and the process ends.

  According to the present embodiment described above, in the voltage detection device of the double flying capacitor type, the leakage failure of one of the two flying capacitors is not provided without separately providing a dedicated circuit for detecting the leakage failure of the two flying capacitors. Can be detected. Thereby, the leakage failure of the flying capacitor can be detected while suppressing the enlargement and cost increase of the voltage detection device.

  Further, in comparison with the technique described in Patent Document 2, in the technique described in Patent Document 2, the abnormality of the voltage measurement circuit can be detected only when the voltage of the battery module becomes the reference voltage. In the embodiment, there is no such limitation, and a leakage failure of the flying capacitor can always be detected.

  As mentioned above, although embodiment which concerns on this invention was described, this invention is not limited to the said embodiment, A various change is possible unless it deviates from the meaning of this invention.

10 voltage detector, 12 a battery, 14 A / D converter, 16 control unit, B0～B13 battery module, IRY0～IRY14 input _relay, C A, _{C B} flying capacitor, ORY0～ORY2 output relay, _OP A, OP _B operational amplifier.

Claims (1)

A voltage detection device that detects a voltage of a battery in which a plurality of first battery modules and a plurality of second battery modules are connected in series,
A first flying capacitor to which power from each first battery module is supplied;
A first voltage measuring circuit for measuring a voltage of each first battery module by measuring a terminal voltage of the first flying capacitor;
A second flying capacitor to which power from each second battery module is supplied;
A second voltage measuring circuit for measuring a voltage of each second battery module by measuring a terminal voltage of the second flying capacitor;
A plurality of measured values obtained by measuring the voltage of each first battery module by the first voltage measuring circuit, and a plurality of measured values obtained by measuring the voltage of each second battery module by the second voltage measuring circuit. And a leakage failure detection means for detecting a leakage failure of one of the first flying capacitor and the second flying capacitor based on the comparison with
A voltage detection apparatus comprising:

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