JP6449585B2 - Battery monitoring system - Google Patents

Description

  The present invention relates to an apparatus for monitoring battery voltage.

  In general, a hybrid vehicle or an electric vehicle (hereinafter simply referred to as a “vehicle”) drives a motor by electric power stored in a chargeable / dischargeable secondary battery such as a lithium ion battery or a hydrogen nickel battery, Driving power is gained. A secondary battery is, for example, a battery in which a plurality of cells are connected in series to form an assembled battery. The vehicle also has a regenerative braking function, that is, a function of braking the vehicle by using the motor as a generator during vehicle braking and converting the kinetic energy of the vehicle into electrical energy. The converted electric energy is charged in the assembled battery. The charged electric energy is discharged when the vehicle accelerates.

  Thus, by repeatedly charging and discharging each cell of the assembled battery, there is a risk that the assembled battery may ignite if a state in which the amount of charge exceeds a predetermined value and the battery is overcharged continues. Further, if the charge amount of each cell of the assembled battery falls below a predetermined value and continues to be overdischarged, the assembled battery may be deteriorated. Therefore, it is necessary to detect the voltage of the cell of the assembled battery and accurately grasp the state of charge. Conventionally, since the cell voltage is measured by a single-system measuring unit, if the measuring unit is abnormal, the measured voltage value may not be an accurate value. As a result, the state of charge cannot be accurately grasped, and overcharge or overdischarge may occur. For this reason, in order to determine whether an abnormality has occurred in the measurement unit that measures the voltage of the cell, a voltage measurement unit of a different system different from the measurement unit is provided, and if both measured values match, it is determined to be normal Therefore, there is a demand for so-called dual cell voltage monitoring.

  For example, in Patent Document 1, a circuit that measures individual voltages of each cell of an assembled battery, a circuit that measures a block voltage having a plurality of cells as a block, and a micro that acquires the voltage of the cells measured by these circuits. A computer is provided in the battery monitoring device. The microcomputer acquires the individual voltages and block voltages of the cells transmitted from the two types of circuits, and determines whether or not the measured values of the two types of circuits are normal based on the acquired voltages. As described above, Patent Document 1 discloses a technique that enables dual battery monitoring.

JP 2011-76777 A

  By the way, when the two types of circuits, a circuit for measuring individual voltages of cells and a circuit for measuring block voltages, and a microcomputer are provided in the battery monitoring device as in Patent Document 1, the microcomputer is relatively high. In order to prevent directly taking in a voltage signal, it is necessary to take measures such as providing an insulation circuit in the microcomputer. As a result, it may cause a significant increase in cost due to an increase in the number of parts. Further, when an insulating circuit or the like is provided, the circuit scale may be increased.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a technique capable of realizing dual battery monitoring without causing a significant increase in manufacturing cost and an increase in circuit scale.

In order to solve the above-mentioned problem, the invention of claim 1 is characterized in that a first individual measuring means for measuring each individual voltage of a plurality of cells included in the first group and each of a plurality of cells included in the second group. A second individual measuring means for measuring an individual voltage; a block measuring means for measuring a block voltage of a block including the first group and the second group; and a first cell voltage signal relating to the individual voltage of the cells of the first group. A pulse transformer that transmits a second cell voltage signal related to an individual voltage of the cells of the second group, a block voltage signal related to a block voltage of the first group and the second group, and the first cell voltage signal A monitoring device that receives the second cell voltage signal and the block voltage signal and determines a measurement state of the voltage of the cell, and 1 individual measurement means, the second individual measuring means, said block measuring means and said pulse transformer is provided on the same substrate, wherein the monitoring device is provided at a position other than on the substrate.

Moreover, the invention of claim 2 is the battery monitoring system according to claim 1 , wherein the first individual measuring means AD converts each individual voltage of the plurality of cells included in the first group, The second individual measuring means AD converts each individual voltage of the plurality of cells included in the second group, and the block measuring means is at least one of the first individual measuring means and the second individual measuring means. One of them is used to AD convert the block voltage.

Further, the invention of claim 3, in the battery monitoring system according to claim 1, wherein the first individual measuring means, based on said voltage measurement request of the monitoring device, some of the cells included in the first group After the individual voltage is measured and the block measuring unit measures the block voltage, the individual voltage of the remaining cells included in the first group is measured, and the second individual measuring unit is configured to measure the voltage of the monitoring device. Based on the request, individual voltages of a plurality of cells included in the second group are measured in a predetermined order.

According to a fourth aspect of the present invention, there is provided a first individual measuring unit for measuring individual voltages of a plurality of cells included in the first group, and a first unit for measuring a group voltage of the plurality of cells included in the first group. 1 group measurement means, 2nd individual measurement means which measures each individual voltage of a plurality of cells contained in the 2nd group, and 2nd group measurement which measures group voltage of a plurality of cells contained in the 2nd group Means, a first cell voltage signal relating to the individual voltage of the first group of cells, a second cell voltage signal relating to the individual voltage of the second group of cells, and a first group voltage signal relating to the group voltage of the first group. A pulse transformer for transmitting a second group voltage signal related to the group voltage of the second group, the first cell voltage signal, and the second cell voltage And a monitoring device that receives the first group voltage signal and the second group voltage signal and determines the measurement state of the voltage of the cell, and includes the first individual measuring means and the first group The measuring means, the second individual measuring means, the second group measuring means, and the pulse transformer are provided on the same substrate, and the monitoring device is provided at a position other than on the substrate, and the first The group measurement means transmits the first group voltage signal to the pulse transformer via a second measurement circuit having the second individual measurement means, and the second group measurement means transmits the second group voltage signal. Is transmitted to the pulse transformer via the first measurement circuit having the first individual measurement means.

According to a fifth aspect of the present invention, in the battery monitoring system according to the fourth aspect , the first individual measurement means is configured to provide individual voltages of some cells included in the first group based on a request from the monitoring device. After the first group measuring means measures the group voltage of the first group, the individual voltage of the remaining cells included in the first group is measured, and the second individual measuring means Based on the request of the apparatus, individual voltages of some cells included in the second group are measured, and the second group measuring means measures the group voltage of the second group, and then included in the second group. Measure the individual voltages of the remaining cells.

  According to the present invention, the battery monitoring system can realize dual battery monitoring without causing a significant increase in manufacturing cost and an increase in circuit scale.

  Further, according to the present invention, not only the block voltage transmitted through one system route via one monitor IC but also the block voltage transmitted through another system route via another monitor IC is determined. By using it, the measurement state of the voltage of the cell of the monitor IC can be determined more accurately.

  In addition, according to the present invention, since the individual voltage and the block voltage of the cell are measured by the AD conversion unit of the monitor IC without providing the AD converter on the satellite substrate, the voltage monitoring is duplicated and the manufacturing cost is increased. Can be suppressed, and an increase in circuit scale can be prevented.

  In addition, according to the present invention, the battery monitoring system can make the difference in measurement timing between the individual voltage of the cell and the block voltage relatively small, and the cell total voltage obtained by summing up the voltages of all the cells and the block voltage. It is possible to prevent a voltage difference as much as possible.

  In addition, according to the present invention, the battery monitoring system is configured to measure the voltage of the cell of the monitor IC by transmitting the group voltage of the cell belonging to one monitor IC to the monitoring device via the other monitor IC. The state can be determined more accurately.

  In addition, according to the present invention, the battery monitoring system can relatively reduce the difference in measurement timing between the individual voltage of the cell and the two group voltages, and the total cell voltage obtained by summing up the voltages of all the cells, 2 It is possible to prevent a voltage difference as much as possible from the block voltage obtained by adding the two group voltages.

FIG. 1 is a diagram showing an outline of a charge / discharge system. FIG. 2 is a block diagram illustrating the configuration of the battery monitoring system according to the first embodiment. FIG. 3 is a diagram for explaining the measurement timing of the individual voltage and the block voltage of the cell. FIG. 4 is a process flowchart of the battery monitoring system. FIG. 5 is a block diagram illustrating a configuration of the battery monitoring system according to the second embodiment. FIG. 6 is a block diagram illustrating the configuration of the battery monitoring system according to the third embodiment. FIG. 7 is a block diagram illustrating the configuration of the battery monitoring system according to the fourth embodiment. FIG. 8 is a diagram for explaining the measurement timing of the individual voltage and the block voltage of the cell. FIG. 9 is a block diagram illustrating the configuration of the battery monitoring system according to the fifth embodiment. FIG. 10 is a diagram for explaining the measurement timing of the individual voltage and the group voltage of the cell. FIG. 11 is a block diagram illustrating the configuration of the battery monitoring system according to the sixth embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<1. First Embodiment>
<1-1. Overview of Charge / Discharge System>
FIG. 1 is a diagram showing an outline of the charge / discharge system ST. The charge / discharge system ST is used as a power source for driving a vehicle such as a hybrid electric vehicle (HEV), an electric vehicle (EV), and a fuel cell vehicle (FCV). The charge / discharge system ST includes the assembled battery 1, a plurality of satellite boards 2 including a monitor IC 12, a monitoring device 21, a vehicle control device 31, a motor 41, a voltage converter 51, and a relay 61. System.

The assembled battery 1 is a battery composed of a plurality of blocks. In one block, 16 cells are connected in series with each other, and these 16 cells are electrically connected to the monitor IC 12 provided on one satellite substrate 2. Therefore, the voltage of each cell in one block is measured by the monitor IC 12 provided on one satellite substrate 2. Note that one satellite substrate 2 is provided with two monitor ICs, a first monitor IC 12a and a second monitor IC 12b, and the first monitor IC 12a and the second monitor 12b bisect cells of one block. Thus, 8 cells are handled as one group.
For this reason, in the charge / discharge system ST, the cell is the minimum unit of the battery, the assembled battery 1 is composed of a plurality of blocks 1a, the block 1a is composed of a plurality of groups, and the group is composed of a plurality of cells.

  Then, based on the voltage measurement request of the monitoring device 21, the AD converter 102 of the monitor IC 12, which will be described later with reference to FIG. 2, measures individual voltages of a plurality of cells included in one block and is provided on the satellite substrate 2. The AD converter 15 measures the block voltages of all the cells included in one block. Further, the monitor IC 12 equalizes the voltage variation of each cell included in one block based on the equalization request from the monitoring device 21. When there is a cell having a relatively high voltage compared to other cells, the monitor IC 12 discharges the cell voltage using a discharge resistor (not shown) provided on a connection line between the cell and the monitor IC 12. Let The monitor IC 12 repeats such discharge to eliminate the voltage variation of each cell included in one block.

  The monitoring device 21 is an electronic control unit (ECU: Electronic Control Unit), and transmits various request signals such as a voltage measurement request and a voltage acquisition request to the monitor IC 12. And the monitoring apparatus 21 receives the signal regarding the voltage of the cell from each monitor IC12 based on these requests | requirements. Specifically, when the unit voltage of the cell is about 3.2 V, the monitoring device 21 receives a signal related to a voltage of about 51.2 V (3.2 × 16 cells) as the voltage of one block, and the entire block, that is, the assembled battery As a voltage of 1, a signal relating to a voltage of about 205V is received. When the voltage of the assembled battery 1 is about 205V in this way, since 16 cells belong to one satellite substrate 2, the charge / discharge system ST has four satellite substrates 2 (eight monitor ICs 12). Will have.

  The monitoring device 21 determines the measurement state of the cell voltage based on the signal related to the cell voltage received from the monitor IC 12. That is, the monitoring device 21 determines whether or not the monitor IC 12 is operating normally based on a signal related to the cell voltage. If the monitoring device 21 determines that the monitor IC 12 is not operating normally and may have failed, the monitoring device 21 performs a fail-safe function. For example, the monitoring device 21 performs a fail-safe function by disconnecting the relay 61 so that charging / discharging of the cell is not performed.

  The vehicle control device 31 charges and discharges the assembled battery 1 in accordance with the state of charge of the assembled battery 1. Specifically, when the assembled battery 1 is overcharged, the vehicle control device 31 converts the voltage charged in the assembled battery 1 from a direct current to an alternating voltage by the voltage converter 51 and drives the motor 41. As a result, the assembled battery 1 is discharged.

  When the assembled battery 1 is overdischarged, the vehicle control device 31 causes the voltage converter 51 to convert the voltage generated by the motor 41 by regenerative braking from an AC voltage to a DC voltage. As a result, the assembled battery 1 is charged with a voltage. As described above, the vehicle control device 31 adjusts the voltage of the assembled battery 1 based on the state of charge of the assembled battery 1 acquired from the monitoring device 21. Next, in such a charge / discharge system ST, the configuration of the battery monitoring system WS that monitors the voltage of the cells of the assembled battery 1 will be described.

<1-2. Configuration of battery monitoring system>
FIG. 2 is a block diagram illustrating the configuration of the battery monitoring system WS. The battery monitoring system WS is a system that includes the satellite substrate 2 and the monitoring device 21. The battery monitoring system WS includes a plurality of satellite substrates 2. However, in order to simplify the description, FIG. 2 illustrates one satellite substrate 2 and one block 1a cell (16 cells) belonging to the satellite substrate 2 as an example. .

  The satellite substrate 2 is a substrate provided with various devices on the substrate. Specifically, the satellite substrate 2 includes two monitor ICs 12, a first monitor IC 12 a and a second monitor IC 12 b, a memory 13, a voltage dividing resistor 14, an AD converter 15, and a pulse transformer 16.

  The first monitor IC 12a measures the individual voltages of each of the eight cells included in one cell group obtained by dividing the 16 cells of the block 1a into two, that is, the first group 10. Specifically, the AD conversion unit 102a of the first monitor IC 12a measures the individual voltages of the cells 10a to 10h included in the first group 10.

  The second monitor IC 12b measures the individual voltage of each of the eight cells included in the other cell group obtained by dividing the 16 cells of the block 1a into two, ie, the second group 11. Specifically, the AD conversion unit 102 b of the second monitor IC 12 b measures the individual voltages of the cells 11 a to 11 h included in the second group 11.

  The individual voltage measurement by the AD conversion unit 102 is executed when the monitor IC 12 receives a voltage measurement request transmitted from the monitoring device 21.

  The individual voltage of each cell of the first group 10 measured by the AD conversion unit 102a is stored in the memory 13a. The individual voltage of each cell of the second group 11 measured by the AD conversion unit 102b is stored in the memory 13b. The memory 13 is a nonvolatile semiconductor memory that stores the cell voltage measured by the AD conversion unit 102 of the monitor IC 12 in this way, and is, for example, an EPROM (Electrical Erasable Programmable Read-Only Memory) or a flash memory. The memory 13 is provided outside the monitor IC, but may be provided inside the monitor IC.

  The battery monitoring system WS measures the block voltage of the block 1a in addition to the individual voltage of the cell. The block voltage is measured when the first monitor IC 12a receives a voltage measurement request from the monitoring device 21. Specifically, when the first monitor IC 12 a receives a voltage measurement request from the monitoring device 21, the AD converter 15 a measures the block voltage of the block 1 a including the first group 10 and the second group 11. More specifically, the AD converter 15a converts the voltage obtained by dividing the voltage of the block 1a by a predetermined resistance ratio into digital values by the voltage dividing resistors 14a and 14b, and outputs the digital value to the first monitor IC 12a. The first monitor IC 12a stores the output voltage value in the memory 13a. The AD converter 15a is provided on the satellite substrate 2 and operates under the control of the first monitor IC 12a.

  Here, the measurement timing of the individual voltage and the block voltage of the cells by the AD conversion unit 102a, the AD conversion unit 102b, and the AD converter 15a will be described with reference to FIG.

<1-3. Measurement timing of individual cell voltage and block voltage>
In FIG. 3, the horizontal axis indicates time, and a device for measuring voltage and a cell or the like to be measured by the device are shown on the time axis. The individual voltages of the cells 10a to 10h of the first group 10 are measured by the AD conversion unit 102a as shown in the upper part of FIG. 3, and the block voltage of the block 1a is measured by the AD converter 15a. The individual voltages of the cells 11a to 11h of the second group 11 are measured by the AD conversion unit 102b as shown in the lower part of FIG. Here, the AD conversion unit 102b measures the individual voltages of the cells of the second group 11 in a predetermined order. Specifically, the AD conversion unit 102 measures the voltages of the four cells 11a to 11d from time t1 to time t2, measures the voltage of the cell 11e from time t2 to time t3, and then measures the voltage of the cell 11h until time t4. Measure the voltage.

  Similarly to the above-described AD conversion unit 102b, the AD conversion unit 102a measures the individual voltages of the cells of the first group 10 in a predetermined order. However, the measurement of the voltage of the AD conversion unit 102a is different from the measurement of the voltage of the AD conversion unit 102b. The AD converter 15a measures the block voltage while the AD converter 102a measures the individual voltages of the cells of the first group 10.

  Specifically, the AD conversion unit 102a measures the voltages of four cells of the cells 10a to 10d of the first group 10 from time t1 to time t2, that is, the individual voltages of some cells included in the first group 10. Next, the AD converter 15a measures the block voltage of the block 1a from time t2 to t3. Thereafter, the AD conversion unit 102 a measures the voltages of the four cells of the cells 10 e to 10 h of the first group 10, that is, the individual voltages of the remaining cells included in the first group 10. As described above, when the AD conversion unit 102a finishes measuring the individual voltages of approximately half of the cells of the first group 10, the AD converter 15a measures the block voltage. After the block voltage is measured, the AD converter 102a measures the individual voltages of the remaining approximately half of the cells. As a result, the battery monitoring system WS can relatively reduce the difference in measurement timing between the individual voltage of the cell and the block voltage, and the voltage difference between the total voltage of all the cells and the block voltage can be as much as possible. It can be prevented from occurring.

  Returning to FIG. 2, the cell voltage value measured based on the voltage measurement request of the monitoring device 21 and stored in the memory 13 is transmitted from each monitor IC 12 to the monitoring device 21 based on the voltage acquisition request of the monitoring device 21. . Specifically, the first monitor IC 12a is based on the voltage acquisition request from the monitoring device 21, and includes the individual voltages of the cells of the first group 10 stored in the memory 13a, and the blocks including the first group 10 and the second group 11. The voltage is read out, and a signal related to the individual voltage of the cells of the first group 10 (hereinafter referred to as “first cell voltage signal”) and a signal related to the block voltage (hereinafter referred to as “block voltage signal”) via the pulse transformer 16a. To the monitoring device 21. Thus, the first cell voltage signal and the block voltage signal read from the memory 13a are transmitted to the monitoring device 21 via the first monitor IC 12a and the pulse transformer 16a.

  Further, the second monitor IC 12b reads out the individual voltages of the second group 11 stored in the memory 13b based on the voltage acquisition request of the monitoring device 21, and signals related to the voltages of the cells of the second group 11 via the pulse transformer 16b. (Hereinafter referred to as “second cell voltage signal”) is transmitted to the monitoring device 21. The second cell voltage signal read from the memory 13b in this way is transmitted to the monitoring device 21 via the second monitor IC 12b and the pulse transformer 16b.

  The pulse transformer 16 is provided between the connection lines between the monitor IC 12 and the monitoring device 21, transmits a signal related to the voltage of the cell, and is relatively high to the monitoring device 21 due to the configuration of the primary winding and the secondary winding. Block the voltage entry.

  The device that measures the voltage of the cell, which is a relatively high voltage, and the device that transmits a signal related to the relatively high voltage are provided on the satellite substrate 2. The device that measures the cell voltage is the AD converter 102 and the AD converter 15 of the monitor IC 12, and the device that transmits a signal related to the cell voltage is the pulse transformer 16. On the other hand, since the monitoring device 21 receives a signal relating to the voltage of the cell via the pulse transformer 16, entry of a relatively high voltage to the monitoring device 21 is blocked. As a result, the monitoring device 21 can be arranged at a position other than the satellite substrate 2. Specifically, the monitoring device 21 can be provided outside the battery pack including the assembled battery 1 and the satellite substrate 2 and having a relatively high voltage (for example, a lower portion of a seat in the vehicle interior). As compared with the case where the battery pack is provided in the battery pack, the restriction on arrangement is eliminated. In addition, it is not necessary to provide an insulation circuit or the like for the monitoring device 21, an increase in the number of parts can be suppressed, and a significant cost increase can be avoided. Furthermore, since an insulating circuit or the like is not necessary, an increase in circuit scale can be prevented.

<1-4. Battery monitoring system processing>
Next, the function of the monitoring device 21 of the battery monitoring system WS will be described. As shown in FIG. 2, the monitoring device 21 mainly includes a measurement request unit 201, an acquisition request unit 202, and a determination unit 203. These functions of the monitoring device 21 will be described using a processing flowchart of the battery monitoring system WS shown in FIG. This flowchart shows the processing of the monitoring device 21 and also shows the processing of the first monitor IC 12a and the second monitor IC 12b communicating with the monitoring device 21. Note that the process shown in FIG. 4 is repeated at a predetermined cycle.

  The measurement request unit 201 of the monitoring device 21 transmits a cell voltage measurement request to the first monitor IC 12a and the second monitor IC 12b (step S101). Specifically, the measurement request unit 201 of the monitoring device 21 transmits a measurement request for the individual voltages of the plurality of cells included in the first group 10 and the block voltage of the block 1a to the first monitor IC 12a. In addition, the measurement request unit 201 transmits a measurement request for individual voltages of a plurality of cells included in the second group 11 to the second monitor IC 12b.

  The first monitor IC 12a and the second monitor IC 12b receive the request signal transmitted from the measurement request unit 201 (steps S201 and S301), so that the AD conversion unit 102a of the first monitor IC 12a is in the first group 10. The individual voltage of the cell is measured, the AD converter 102b of the second monitor IC 12b measures the individual voltage of the cell of the second group 11, and the AD converter 15a measures the block voltage of the block 1a (steps S202 and 302). . The measured individual voltage of the cell and the voltage value of the block voltage are stored in the memory 13.

  Next, the acquisition request unit 202 of the monitoring device 21 transmits a voltage acquisition request to the first monitor IC 12a and the second monitor IC 12b (step S102). Specifically, the acquisition request unit 202 transmits an acquisition request for the individual voltages of the cells of the first group 10 and the block voltage of the block 1a to the first monitor IC 12a. The acquisition request unit 202 transmits an acquisition request for the individual voltages of the cells in the second group 11 to the second monitor IC 12b.

  The first monitor IC 12a and the second monitor IC 12b receive each voltage value from the memory 13 by receiving the voltage acquisition request transmitted from the acquisition request unit 202 (steps S203 and S303), and the first cell voltage signal Then, the second cell voltage signal and the block voltage signal are transmitted to the monitoring device 21 via the pulse transformer 16 (steps S204 and S304).

  The monitoring device 21 receives a signal regarding each voltage transmitted through the pulse transformer 16 (step S103). The determination unit 203 of the monitoring device 21 determines the measurement state of the cell voltage based on the first cell voltage signal, the second cell voltage signal, and the block voltage signal acquired from the monitor IC 12 (step S104). Specifically, the determination unit 203 compares the cell total voltage obtained by summing the voltages based on the first cell voltage signal and the second cell voltage signal with the block voltage based on the block voltage signal.

  When the voltage difference between the total cell voltage and the block voltage is equal to or greater than a predetermined value (Yes in step S104), the determination unit 203 determines that at least one of the two monitor ICs 12 is in an abnormal state, that is, has failed. It is determined that As a result, the monitoring device 21 disconnects the relay 61 (step S105). As a result, the battery monitoring system WS can realize dual battery monitoring and improve the reliability of the cell voltage abnormality determination. The battery monitoring system WS can immediately stop charging / discharging of the cell when the monitor IC 12 is out of order, and can ensure the safety of the user of the vehicle.

  When the voltage difference between both is less than the predetermined value in step S104 (No in step S104), the determination unit 203 determines that the two monitor ICs 12 are in the normal state, and the process ends.

  4 has been described by taking communication and processing between the monitoring device 21 and the two monitor ICs 12 as an example. Actually, the monitoring device 21 is connected to each of the monitor ICs 12 provided on the plurality of satellite substrates 2. The measurement state of the cell voltage is determined based on the transmitted individual voltage or block voltage of the cell.

<1-5. Summary>
As described above, in the battery monitoring system WS according to the first embodiment, the device that measures the cell voltage that is a relatively high voltage and the device that transmits a signal related to the relatively high voltage are provided on the same substrate. It is done. The device that measures the cell voltage is the AD converter 102 and the AD converter 15 of the monitor IC 12, and the device that transmits a signal related to the cell voltage is the pulse transformer 16. On the other hand, since the monitoring device 21 receives a signal relating to the voltage of the cell via the pulse transformer 16, entry of a relatively high voltage to the monitoring device 21 is blocked. As a result, the monitoring device 21 can be arranged at a position other than the satellite substrate 2. Specifically, the monitoring device 21 can be provided outside the battery pack including the assembled battery 1 and the satellite substrate 2 and having a relatively high voltage (for example, a lower portion of a seat in the vehicle interior). As compared with the case where the battery pack is provided in the battery pack, the restriction on arrangement is eliminated. In addition, it is not necessary to provide an insulation circuit or the like for the monitoring device 21, an increase in the number of parts can be suppressed, and a significant cost increase can be avoided. In addition, since an insulating circuit or the like is not necessary, an increase in circuit scale can be prevented.

  Then, the individual voltage and the block voltage of the cell are measured by the AD converter 102 and the AD converter 15 provided on the satellite substrate 2 according to the voltage measurement request of the monitoring device 21, and these voltages are measured according to the voltage acquisition request of the monitoring device 21. Is transmitted to the monitoring device 21. As a result, the monitoring device 21 determines the measurement state of the cell voltage by the monitor IC 12 based on the total cell voltage and the block voltage, and disconnects the relay 61 when determining that the monitor IC 12 is out of order, The charging / discharging of the voltage to the assembled battery 1 is stopped. As a result, the battery monitoring system WS can realize dual battery monitoring and improve the reliability of the cell voltage abnormality determination. The battery monitoring system WS can immediately stop charging / discharging of the cell when the monitor IC 12 is out of order, and can ensure the safety of the user of the vehicle. In this way, the battery monitoring system WS can realize dual battery monitoring without causing a significant increase in manufacturing cost or an increase in circuit scale.

  Further, when the number of cells in the block 1a in the present embodiment is changed from 16 cells to 8 cells, the AD conversion unit 102 of one monitor IC 12 measures individual voltages of a plurality of cells included in one group, and AD The converter 15 measures the group voltage of all the cells included in the group. Then, the monitor IC 12 transmits the first cell voltage signal related to the individual voltage of the cells in the group and the first group voltage signal related to the group voltage of the first group to the monitoring device 21 via the pulse transformer 16. The monitor IC 12, the AD converter 15, and the pulse transformer 16 are provided on the satellite substrate 2 on the same substrate, and the monitoring device 21 is disposed at a position other than the satellite substrate 2. And the monitoring apparatus 21 determines the measurement state of the voltage of a cell with a 1st cell voltage signal and a 1st group voltage signal. Thereby, the battery monitoring system WS can realize dual battery monitoring without causing a significant increase in manufacturing cost and an increase in circuit scale.

<2. Second Embodiment>
Next, a second embodiment will be described. In the first embodiment, the block voltage measured by the AD converter 15a has been described as being output to the first monitor IC 12a and stored in the memory 13a. On the other hand, in the second embodiment, the block voltage is also output to the second monitor IC 12b and stored in the memory 13b that is electrically connected to the second monitor IC 12b.

  The configuration and processing of the battery monitoring system WS of the second embodiment are substantially the same as those of the first embodiment, but the path of the signal output from the AD converter 15a is partially different. Hereinafter, a description will be given with reference to FIG.

<2-1. Configuration of battery monitoring system>
FIG. 5 is a diagram illustrating a configuration of the battery monitoring system WS according to the second embodiment. In the battery monitoring system WS of FIG. 5, the block voltage measured by the AD converter 15a is output to each of the first monitor IC 12a and the second monitor IC 12b. The first monitor IC 12a stores the voltage value of the block voltage in the memory 13a, and the second monitor IC 12b stores the voltage value of the block voltage in the memory 13b.

  Then, based on the voltage acquisition request of the acquisition request unit 202 of the monitoring device 21, the first monitor IC 12a obtains the voltage value of the individual voltage of the cells of the first group 10 and the voltage value of the block voltage of the block 1a from the memory 13a. Reading, the first cell voltage signal and the block voltage signal are transmitted to the monitoring device 21 via the pulse transformer 16a. Further, the second monitor IC 12b reads the voltage value of the individual voltage of the cells of the second group 11 and the voltage value of the block voltage from the memory 13b based on the voltage acquisition request, and outputs the second cell voltage signal and the block voltage signal. Is transmitted to the monitoring device 21 via the pulse transformer 16b.

  The determination unit 203 of the monitoring device 21 transmits the first cell voltage signal, the second cell voltage signal, the first block voltage signal transmitted via the first monitor IC 12a, and the second monitor IC 12b. The measurement state of the voltage of the cell of the monitor IC 12 is determined based on the second block voltage signal. Specifically, the determination unit 203 includes a cell total voltage obtained by summing voltages based on the first cell voltage signal and the second cell voltage signal, a first block voltage based on the first block voltage signal, and a second block. The three voltages with the second block voltage based on the voltage signal are compared, and if there is a voltage difference of a predetermined value or more between these voltages, the monitor IC 12 is determined to be in an abnormal state. Thereby, the battery monitoring system WS not only transmits the first block voltage transmitted through one system route via one monitor IC 12, but also transmits the second block transmitted through another system route via another monitor IC 12. By using the block voltage for the determination, the measurement state of the voltage of the cell of the monitor IC 12 can be determined more accurately.

<3. Third Embodiment>
Next, a third embodiment will be described. In the third embodiment, a switch 17 (17a to 17d) and a capacitor 18a are provided in place of the voltage dividing resistors 14a and 14b provided on the satellite substrate 2 of the second embodiment. is there.

  The configuration and processing of the battery monitoring system WS of the third embodiment are substantially the same as those of the second embodiment, but the circuit configuration in which the AD converter 15a measures the block voltage is partially different. Hereinafter, a description will be given with reference to FIG.

<3-1. Configuration of battery monitoring system>
FIG. 6 is a block diagram illustrating the configuration of the battery monitoring system according to the third embodiment. The satellite substrate 2 of FIG. 6 is provided with a capacitor 18a. When the AD converter 15a measures the block voltage, the electric charge accumulated in the capacitor 18a is output to the AD converter 15a, and the block voltage is measured. Specifically, the first monitor IC 12a switches on the switches 17a and 17b at the timing of measuring the block voltage of the block 1a based on the voltage measurement request of the measurement request unit 201 of the monitoring device 21. When the switches 17a and 17b are turned on, the charges of all the cells included in the block 1a, that is, the charges of the block flow into the capacitor 18a. Next, the first monitor IC 12a turns off the switches 17a and 17b, and then turns on the switches 17c and 17d. As a result, the block charges accumulated in the capacitor 18a are output to the AD converter 15a, and the block voltage is measured. Thus, by providing the switch 17 and the capacitor 18a, the battery monitoring system WS can measure the block voltage more accurately at the timing of measuring the block voltage.

<4. Fourth Embodiment>
Next, a fourth embodiment will be described. In the fourth embodiment, the AD converter 15a of the first monitor IC 12a and the AD converter 102b of the second monitor IC 12b are provided without providing the AD converter 15a that measures the block voltage on the satellite substrate 2. The block voltage is measured.

  The configuration and processing of the battery monitoring system WS of the fourth embodiment are almost the same as those of the second embodiment, but the configuration for measuring the block voltage by the AD converter 102 instead of the AD converter 15a is different. . Hereinafter, a description will be given with reference to FIGS.

<4-1. Configuration of battery monitoring system>
FIG. 7 is a block diagram illustrating a configuration of the battery monitoring system WS according to the fourth embodiment. In the battery monitoring system WS of FIG. 7, a switch W1 is provided between the connection lines between the first monitor IC 12a of the satellite substrate 2 and the positive terminal of the cell 10h of the first group 10. The switch W1 has terminals T1a and T1b. When the switch W1 is connected to the terminal T1a, the AD conversion unit 102a measures the individual voltage of the cell 10h. When the switch W1 is connected to the terminal T1b side, the AD conversion unit 102a measures the block voltage of the block 1a. The switch W1 shown in FIG. 7 is connected to the terminal T1b, and the control of the switch W1 is performed by the first monitor IC 12a based on a voltage measurement request from the measurement request unit 201 of the monitoring device 21.

  A switch W2 is provided between the connection lines between the second monitor IC 12b and the positive terminal of the cell 11h of the second group 11. The switch W2 has terminals T2a and T2b. When the switch W2 is connected to the terminal T2a, the AD converter 102b measures the individual voltage of the cell 11h. When the switch W2 is connected to the terminal T2b side, the AD conversion unit 102a measures the block voltage. Note that the switch W2 illustrated in FIG. 7 is connected to the terminal T2a side, and the control of the switch W2 is performed by the monitor IC 12b based on a voltage measurement request from the measurement request unit 201.

  Next, the measurement timing of the individual voltage and the block voltage of the cells by the AD conversion unit 102a and the AD conversion unit 102b will be described with reference to FIG.

<4-2. Measurement timing of individual cell voltage and block voltage>
In FIG. 8, the AD conversion unit 102a and the AD conversion unit 102b measure individual voltages of some cells from time t1 to time t2. Specifically, the AD conversion unit 102a measures the voltages of the cells 10a to 10d, and the AD conversion unit 102b measures the voltages of the cells 11a to 11d.

  Next, the AD conversion unit 102a and the AD conversion unit 102b measure the block voltage from time t2 to time t3. Specifically, the AD conversion unit 102a measures the block voltage of the block 1a, and the AD conversion unit 102b also measures this block voltage. At this time, the first monitor IC 12a controls the switch W1 to be connected to the terminal T1b side, and the second monitor IC 12b controls the switch W2 to be connected to the terminal T2b side.

  Thereafter, the AD conversion unit 102a and the AD conversion unit 102b measure the individual voltages of the remaining cells from time t3 to t5. Specifically, the AD conversion unit 102a measures the voltages of the cells 10e to 10h, and the AD conversion unit 102b measures the voltages of the cells 11e to 11h. At this time, the first monitor IC 12a controls the switch W1 to be connected from the terminal T1b side to the T1a side before measuring the voltage of the cell 10h (before the time t4). Further, the second monitor IC 12b controls the switch W2 to be connected from the terminal T2b side to the terminal T2a side before the voltage of the cell 11h is measured (before the time t4).

  Thus, since the individual voltage and the block voltage of the cell are measured by the AD converter 102 of the monitor IC 12 without providing the AD converter 15 on the satellite substrate 2, the voltage monitoring is duplicated and the manufacturing cost is increased. Can be suppressed, and an increase in circuit scale can be prevented.

<5. Fifth embodiment>
Next, a fifth embodiment will be described. In the fifth embodiment, two AD converters 15 are provided on the satellite substrate 2, and these AD converters 15 use not the block voltage of the block 1 a but the voltage for each of the groups of the first group 10 and the second group 11. Measure. The voltage of each group is output to the monitor IC 12 included in the AD conversion unit 102 that measures individual voltages of different groups.

<5-1. Configuration of battery monitoring system>
The configuration and processing of the battery monitoring system WS of the fifth embodiment are almost the same as those of the first embodiment, but the group voltage is measured instead of the block voltage, and the group voltage output path. Etc. are different. Hereinafter, description will be made with reference to FIGS. 9 and 10.

  FIG. 9 is a block diagram illustrating the configuration of the battery monitoring system WS according to the fifth embodiment. In the battery monitoring system WS of FIG. 9, two AD converters 15 of AD converters 15 b and 15 c are provided on the satellite substrate 2. The AD converter 15b measures the total voltage of the cells 10a to 10h included in the first group 10 (hereinafter referred to as “first group voltage”). Further, the AD converter 15 c measures the total voltage (hereinafter referred to as “second group voltage”) of the cells 11 a to 11 h included in the second group 11. The voltage of the first group 10 is divided by the voltage dividing resistors 14c and 14d at a predetermined resistance ratio and output to the AD converter 15b. The voltage of the second group 11 is divided by a predetermined resistance ratio by the voltage dividing resistors 14e and 14f and output to the AD converter 15c.

  The AD converter 15b outputs the first group voltage to the second monitor IC 12b. On the other hand, the AD conversion unit 102b of the second monitor IC 12b measures the individual voltage of the second group 11. The AD converter 15c outputs the second group voltage to the first monitor IC 12a. In contrast, the AD conversion unit 102a of the first monitor IC 12a measures the individual voltage of the first group 10. As described above, the individual voltage of the group measured by the AD converter 102 of the monitor IC 12 and the group voltage measured by the AD converter 15 and output to the monitor IC 12 are the individual voltage and group voltage of different groups. Therefore, the memory 13a stores the individual voltage values of the cells of the first group 10 and the group voltage value of the second group 11, and the memory 13b stores the individual voltage values of the cells of the second group 11 and the first group. Ten group voltage values are stored.

  Then, the monitor IC 12 transmits the voltage value stored in the memory 13 to the monitoring device 21 via the pulse transformer 16 based on the voltage acquisition request of the acquisition request unit 202 of the monitoring device 21. Specifically, the first monitor IC 12a transmits the first cell voltage signal and the second group voltage signal related to the voltage value of the second group to the monitoring device 21 via the pulse transformer 16a. The second monitor IC 12b transmits the second cell voltage signal and the first group voltage signal related to the voltage value of the first group to the monitoring device 21 via the pulse transformer 16b. For the transmission of the signal related to such a voltage, the first group voltage measured by the AD converter 15b is transmitted via the second monitor IC 12b having the AD converter 102b, and the first voltage measured by the AD converter 15c is transmitted. It can be said that the two group voltages are transmitted via the first monitor IC 12a having the AD conversion unit 102a.

  The determination unit 203 of the monitoring device 21 includes a cell total voltage based on the first cell voltage signal and the second cell voltage signal, and a group total voltage based on a voltage obtained by summing the first group voltage signal and the second group voltage signal. If the voltage difference between the two is equal to or greater than a predetermined value, it is determined that the monitor IC 12 is in an abnormal state. In such a case, the determination unit 203 determines that at least one of the two monitor ICs 12 is in an abnormal state, that is, has failed.

  In the battery monitoring system WS of the present embodiment, the AD converter 15b measures the group voltage of one group (second group 11) and outputs the group voltage of one group to the first monitor IC 12a. The first monitor IC 12a includes an AD conversion unit 102a that measures individual voltages of the cells of the other group (first group 10). Therefore, individual voltages of different groups and group voltages are transmitted to the monitoring device 21 via the first monitor IC 12a.

  The AD converter 15c measures the group voltage of the other group and outputs the group voltage of the other group to the second monitor IC 12b. The second monitor IC 12b includes an AD conversion unit 102b that measures individual voltages of one group of cells. Therefore, individual voltages of different groups and group voltages are transmitted to the monitoring device 21 via the second monitor IC 12b. As a result, the battery monitoring system WS can more accurately determine the measurement state of the cell voltage of the monitor IC 12.

<5-2. Measurement timing of individual cell voltage and block voltage>
In FIG. 10, the AD conversion unit 102a and the AD conversion unit 102b measure individual voltages of some cells included in the group from time t1 to time t2. Specifically, the AD conversion unit 102a measures the voltages of the cells 10a to 10d of the first group 10, and the AD conversion unit 102b measures the voltages of the cells 11a to 11d of the second group 11.

  Next, the AD converter 15b and the AD converter 15c measure the group voltage from time t2 to time t3. Specifically, the AD converter 15 b measures the first group voltage of the first group 10, and the AD converter 15 c measures the second group voltage of the second group 11. Thereafter, the AD conversion unit 102a and the AD conversion unit 102b measure the individual voltages of the remaining cells in the group from time t3 to t5. Specifically, the AD conversion unit 102a measures the voltages of the cells 10e to 10h of the first group 10, and the AD conversion unit 102b measures the voltages of the cells 11e to 11h of the second group 11.

  In the battery monitoring system WS of the present embodiment, the AD converter 15b measures the group voltage of the first group 10 when the AD converter 102a finishes measuring the individual voltages of about half of the cells of the first group 10. To do. After measuring the group voltage, the AD converter 102a measures the individual voltages of the remaining approximately half of the cells. Further, when the AD conversion unit 102b finishes measuring the individual voltages of about half of the cells of the second group 11, the AD converter 15c measures the group voltage of the second group 11. The AD converter 102b measures the individual voltages of the remaining approximately half of the cells. As a result, the battery monitoring system WS can relatively reduce the difference in measurement timing between the individual voltage of the cell and the two group voltages, and the total cell voltage obtained by adding up the voltages of all the cells and the two group voltages. It is possible to prevent a voltage difference from occurring as much as the total block voltage.

<6. Sixth Embodiment>
Next, a sixth embodiment will be described. In the sixth embodiment, a switch 17 (17e to 17h) and a capacitor 18b are provided in place of the voltage dividing resistors 14c and 14d provided on the satellite substrate 2 of the fifth embodiment. is there. Further, instead of the voltage dividing resistors 14e and 14f, a switch 17 (17m to 17p) and a capacitor 18c are provided.

  The configuration and processing of the battery monitoring system WS of the sixth embodiment are substantially the same as those of the fifth embodiment, but the AD converters 15b and 15c are partially different in circuit configuration for measuring the group voltage. Hereinafter, a description will be given with reference to FIG.

<6-1. Configuration of battery monitoring system>
FIG. 11 is a block diagram illustrating the configuration of the battery monitoring system according to the sixth embodiment. The satellite substrate 2 in FIG. 11 is provided with a capacitor 18b and a capacitor 18c. When the AD converter 15b measures the group voltage of the first group 10, the charge accumulated in the capacitor 18b is output to the AD converter 15b, and the first group voltage is measured. Specifically, the first monitor IC 12a switches on the switches 17e and 17f at the timing of measuring the first group voltage based on the voltage measurement request. When the switches 17e and 17f are turned on, the charges of all the cells included in the first group 10 flow into the capacitor 18b. Next, the first monitor IC 12a turns off the switches 17e and 17f, and then turns on the switches 17g and 17h. As a result, the charge of the first group 10 accumulated in the capacitor 18b is output to the AD converter 15b, and the first group voltage is measured.

  Further, when the AD converter 15c measures the group voltage of the second group 11, the charge accumulated in the capacitor 18c is output to the AD converter 15c, and the second group voltage is measured. Specifically, the second monitor IC 12b switches on the switches 17m and 17n at the timing of measuring the second group voltage based on the voltage measurement request of the measurement request unit 201. When the switches 17m and 17n are turned on, the charges of all the cells included in the second group 11 flow into the capacitor 18c. Next, after the second monitor IC 12b switches off the switches 17m and 17n, the switches 17o and 17p are switched on. As a result, the charge of the second group 11 accumulated in the capacitor 18c is output to the AD converter 15c, and the second group voltage is measured. As described above, by providing the switch 17 and the capacitor 18, the battery monitoring system WS can measure the group voltage more accurately at the timing of measuring the group voltage.

<7. Modification>
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications are possible. Below, such a modification is demonstrated. All the forms including the above-described embodiment and the form described below can be appropriately combined.

  In the above embodiment, the number of cells in one group has been described as 16, but the number of cells in one group may be other than 16.

  In the above embodiment, the number of cells belonging to one monitor IC 12 is described as eight. However, the number of cells belonging to one monitor IC 12 may be other than eight.

  In the above embodiment, the number of monitor ICs 12 included in one satellite substrate is described as two. However, the number of monitor ICs 12 may be other than two.

  In the above embodiment, it has been described that the measurement of the cell voltage is performed in a predetermined cycle. Here, the voltage of the cell fluctuates relatively greatly depending on the traveling state of the vehicle. Therefore, the monitoring device 21 transmits a voltage measurement request to the monitor IC 12 when the vehicle is traveling at a relatively low speed or when the vehicle is stopped, and the AD converter 102 or the AD converter 15 measures the cell voltage. You may make it do.

  Further, in the above-described embodiment, it has been described that various functions are realized in software by the arithmetic processing of the CPU according to the program. However, some of these functions are realized by an electrical hardware circuit. Also good. Conversely, some of the functions realized by the hardware circuit may be realized by software.

  In the first embodiment, the block voltage measurement by the AD converter 15a is executed under the control of the first monitor IC 12a. On the other hand, the block voltage measurement by the AD converter 15a may be executed under the control of the second monitor IC 12b. In this case, the block voltage measurement at times t2 to t3 described with reference to FIG. 4 is executed by the AD conversion unit 102b instead of the AD conversion unit 102a.

  In the fourth embodiment, the AD converter 102a measures the individual voltages and block voltages of the cells in the first group 10, and the AD converter 102b uses the individual voltages of the cells in the second group 11. And measuring the block voltage. On the other hand, each of the AD conversion units 102a and 102b may measure only the block voltage without measuring the individual voltage of the cell. Then, the determination unit 203 may determine the measurement state of the voltage of the cell of the monitor IC 12 based on the block voltage measured by the two AD conversion units 102. Thereby, the battery monitoring system WS does not need to match the measurement timing of the individual voltage of the cell and the block voltage, and the process of determining the measurement state of the cell voltage of the monitor IC 12 can be simplified.

  In the fourth embodiment, the first monitor IC 12a controls the switch W1 and the second monitor IC 12b controls the switch W2, so that the block voltage is converted into two AD conversion units, AD conversion units 102a and 102b. The conversion at 102 has been described. On the other hand, the block voltage may be converted by one of the AD converters 102a and 102b.

  Further, the AD converter 15a of the first monitor IC 12a and the AD converter of the second monitor IC 12b are provided without providing the AD converter 15a for measuring the block voltage on the satellite substrate 2 described in the fourth embodiment. The configuration for measuring the block voltage by 102b can be applied to other embodiments. For example, it can be applied to the battery monitoring system WS of the third embodiment.

1 assembled battery 2 satellite substrate 21 monitoring device 31 vehicle control device 41 motor 51 voltage converter 61 relay

Claims (5)

First individual measuring means for measuring individual voltages of a plurality of cells included in the first group;
A second individual measuring means for measuring individual voltages of a plurality of cells included in the second group;
Block measuring means for measuring a block voltage of a block including the first group and the second group;
A first cell voltage signal relating to an individual voltage of the first group of cells; a second cell voltage signal relating to an individual voltage of the second group of cells; and a block voltage signal relating to a block voltage of the first group and the second group. And a pulse transformer that transmits
A monitoring device that receives the first cell voltage signal, the second cell voltage signal, and the block voltage signal to determine a measurement state of the voltage of the cell;
With
The first individual measuring means, the second individual measuring means, the block measuring means, and the pulse transformer are provided on the same substrate,
The monitoring device is provided at a position other than on the substrate;
A battery monitoring system. The battery monitoring system according to claim 1 ,
The first individual measuring means AD converts each individual voltage of the plurality of cells included in the first group,
The second individual measuring means AD converts each individual voltage of the plurality of cells included in the second group,
The block measuring means AD-converts the block voltage using at least one of the first individual measuring means and the second individual measuring means;
A battery monitoring system. The battery monitoring system according to claim 1 ,
The first individual measuring unit measures individual voltages of some cells included in the first group based on a voltage measurement request of the monitoring device, and after the block measuring unit measures the block voltage, Measure the individual voltages of the remaining cells in the first group,
The second individual measuring means measures the individual voltages of a plurality of cells included in the second group in a predetermined order based on a voltage measurement request of the monitoring device;
A battery monitoring system. First individual measuring means for measuring individual voltages of a plurality of cells included in the first group;
First group measurement means for measuring a group voltage of a plurality of cells included in the first group;
A second individual measuring means for measuring individual voltages of a plurality of cells included in the second group;
Second group measurement means for measuring a group voltage of a plurality of cells included in the second group;
A first cell voltage signal relating to an individual voltage of the first group of cells; a second cell voltage signal relating to an individual voltage of the second group of cells; a first group voltage signal relating to the group voltage of the first group; A pulse transformer for transmitting a second group voltage signal relating to the group voltage of the second group;
A monitoring device that receives the first cell voltage signal, the second cell voltage signal, the first group voltage signal, and the second group voltage signal and determines a measurement state of the voltage of the cell;
With
The first individual measuring means, the first group measuring means, the second individual measuring means, the second group measuring means, and the pulse transformer are provided on the same substrate,
The monitoring device is provided at a position other than on the substrate,
The first group measuring means, said first group voltage signal, via the second measuring circuit having the second individual measuring means is transmitted to the pulse transformer,
The second group measuring means, said second group voltage signals, be transmitted via the first measuring circuit having a first individual measuring means to said pulse transformer,
A battery monitoring system. The battery monitoring system according to claim 4 , wherein
The first individual measuring unit measures individual voltages of some cells included in the first group based on a request of the monitoring device, and the first group measuring unit measures a group voltage of the first group. And measuring the individual voltages of the remaining cells included in the first group,
The second individual measuring unit measures individual voltages of some cells included in the second group based on a request from the monitoring device, and the second group measuring unit measures a group voltage of the second group. And measuring individual voltages of the remaining cells included in the second group,
A battery monitoring system.

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