JP2022175762A - Battery monitoring device - Google Patents

Abstract

To provide a battery monitoring device that is capable of not only coping with different filter circuit configurations, but also reducing the number of switch elements required for switching between a normal route and diagnostic route.SOLUTION: Unit cells I1 to I25 are divided into groups, namely, an upside cell group 1U and a downside cell group 1D, and a battery monitoring device 11 is connected to each group via a filter circuit group 2. The battery monitoring device 11 is provided with upside and downside AFE circuits 7U and 7D having AD converters 8U and 8D incorporated, respectively. A multiplexer 4 is configured with a plurality of switch elements 3 each with one end connected individually to a terminal V or a terminal S, and with the other end connected to any of four wires in upside and downside wire parts 5U and 5D. Six polarity inversion switches 6(U1) to 6(D3) constituted of a plurality of switch elements 9 are arranged between a division wire part 5 and differential input terminals of the AFE circuits 7U 7D.SELECTED DRAWING: Figure 1

Description

The present invention relates to a device that is connected via a filter circuit to an assembled battery configured by connecting a plurality of unit cells in series and that monitors each unit cell.

The filter circuits connected to each unit cell that constitutes the assembled battery can be roughly classified into a single RC type also called a semi-common type shown in FIG. There are two types, the ground type. The configuration of the filter is determined according to the specifications required by the OEM (Original Equipment Manufacturer). If the configuration of the filter circuit is different, the terminal to be detected by the monitoring device is also different, so the wiring route inside the monitoring device is also different.

In addition, in order to monitor a unit cell, in general, a normal path for detecting the terminal voltage of the unit cell and a diagnostic path for detecting a failure using a voltage drop in a resistive element provided in the filter circuit are used. need to switch. As shown in FIGS. 32 and 33, four terminals Vn, Sn, Sn+1, Vn-1 are provided corresponding to one unit cell.

In the case of the single RC type shown in FIG. 32, the normal path is between terminals Vn-Sn, and the diagnostic path is between terminals Sn+1-Vn-1. On the other hand, in the case of the ground type shown in FIG. 33, the normal path is between terminals Vn-Vn-1, and the diagnostic path is between terminals Sn+1-Sn. When the filter circuit is of the π type, the lower end of the capacitor whose upper end is connected to the terminal Vn in FIG. 32 is connected to the terminal Vn-1 instead of the ground. In the separated filter circuit shown in FIG. 33, the terminal V is used as a detection-dedicated terminal for the detection path of the normal path, and the terminal S is used as an equalization-dedicated terminal for the equalization path. ing. On the other hand, in the semi-common type filter circuit shown in FIG. has become semi-common.

Japanese Patent No. 5858094

As described above, it is difficult for a single monitoring device to handle both single RC-type and π-type or ground-type filter circuits with different detection paths, and it is difficult to simply switch between the normal path and the diagnostic path. Then, the number of switch elements constituting the multiplexer is doubled.

The present invention has been made in view of the above circumstances, and its object is to be able to cope with different configurations of filter circuits and to reduce the number of switch elements required for switching between the normal path and the diagnostic path. An object of the present invention is to provide a battery monitoring device.

According to the battery monitoring apparatus of claim 1, a plurality of unit cells are grouped into an upper cell group and a lower cell group and connected via a filter circuit group. One end of a multiplexer is connected to the first terminal side and the second terminal side of each unit cell, and the other end is connected to any one of the odd first wiring and even first wiring, the odd second wiring and the even second wiring. It consists of a plurality of switch elements that are connected to each other.

Upper and lower front-end circuits with built-in A/D converters are provided, and between each wiring and the differential input terminals of each front-end circuit, it is possible to invert the input polarity to the differential input terminals. are arranged in association with each other as follows.
Higher order odd and even numbered first wiring - higher order front end circuit: upper side first switch group Upper order odd and even numbered second wiring - higher order front end circuit: upper side second switch group Upper order odd and even numbered second wiring - Lower side front-end circuit: Upper side third switch group Lower side odd and even numbered first wiring - Lower side front end circuit: Lower side first switch group Lower side odd and even numbered second wiring - Lower side front end circuit: Lower Side 2nd switch group Low side even and even number 1st wiring - Higher side front end circuit: Lower side 3rd switch group Note that the connection of the upper side 3rd switch group and the lower side 3rd switch group should be replaced with the above connection. You can also connect in the following combinations.
Upper side odd and even numbered first wiring - lower side front end circuit: upper side third switch group Lower side odd and even numbered second wiring - upper side front end circuit: lower side third switch group In claim 1, It should be noted here that the connection relationship of "or" described for the upper third switch group and the lower third switch group is not arbitrary, and that there is a correspondence relationship between the two as described above.

That is, by providing an upper-side front-end circuit for the upper-side cell group and providing a lower-side front-end circuit for the lower-side cell group, the voltage can be measured independently for each cell group. Further, the multiplexer and each switch group are connected to each other on the upper side and the lower side through four wirings consisting of odd and even first wirings and odd and even second wirings and polarity reversing switches. , it is possible to suppress an increase in the number of switch elements constituting the multiplexer.

Furthermore, by providing a third upper switch group connectable to the lower front end circuit and a third lower switch group connectable to the upper front end circuit, the upper and lower cell groups and the upper The connections between the side and the lower side front-end circuits can be switched more flexibly, allowing simultaneous detection of normal and diagnostic paths.

According to the battery monitoring device of claim 2, the control circuit controls the multiplexer, the first to third switch groups on the upper side and the first to third switch groups on the lower side, thereby adjusting the voltage of each unit cell. A normal path for detection and a diagnostic path for detecting a voltage to be compared with the voltage when a fault occurs in the path from the unit cell to the front end circuit are switched. By controlling in this manner, fault detection can be performed by comparing the voltages measured by switching between the normal path and the diagnostic path for each cell group.

According to the battery monitoring device of claim 3, the control circuit controls such that one front-end circuit detects the voltage of the unit cell of the upper-side cell group through the normal path, and the other front-end circuit detects the voltage of the lower-side unit cell. It controls to detect the voltage of the unit cell of the cell group through the normal path. As a result, it is possible to perform voltage measurement for each cell group in parallel using the normal route.

According to the battery monitoring device of claim 4, the control circuit controls such that one front-end circuit detects the voltage of the unit cell of the upper-side cell group through the diagnostic path, and the other front-end circuit detects the voltage of the lower-side unit cell. The voltage of the unit cells of the cell group is controlled to be detected by the diagnostic path. As a result, it is possible to perform voltage measurement in parallel on each cell group through the diagnostic path.

1 is a diagram showing the configuration of a battery monitoring device according to a first embodiment; FIG. FIG. 10 is a diagram showing a control sequence in which two AFE circuits are connected in parallel to the normal path and diagnostic path for each unit cell of the lower cell group when the filter circuit is of the π type/ground type; FIG. 4 is a diagram showing a control sequence in which two AFE circuits are connected in parallel to a normal path and a diagnostic path for each unit cell of the upper cell group; A diagram showing a connection path when the object to be measured is the unit cell I1. FIG. 11 shows a connection path when the object to be measured is the unit cell I12; FIG. 4 shows a connection path when the unit cell I13 is the object to be measured; A diagram showing a connection path when the object to be measured is the unit cell I24. A diagram showing a connection path when the object to be measured is the unit cell I25. FIG. 10 is a diagram showing a control sequence for connecting each unit cell of the upper-side and lower-side cell groups to the normal path when the filter circuit is the π-type/ground-type filter circuit according to the second embodiment; FIG. 10 is a diagram showing connection paths when the objects to be measured are the unit cells I1 and I13; A diagram showing connection paths when the objects to be measured are the unit cells I2 and I14. A diagram showing a connection path when the measurement objects are the unit cells I12 and I24. A diagram showing a connection path when the object to be measured is the unit cell I25. FIG. 11 is a diagram showing a control sequence for connecting each unit cell of the upper side and lower side cell groups to the diagnosis path when the filter circuit is of the π type/ground type according to the third embodiment; FIG. 10 is a diagram showing connection paths when the objects to be measured are the unit cells I1 and I13; A diagram showing connection paths when the objects to be measured are the unit cells I2 and I14. A diagram showing a connection path when the measurement objects are the unit cells I12 and I24. A diagram showing a connection path when the object to be measured is the unit cell I25. FIG. 14 is a diagram showing a control sequence for connecting each unit cell of the upper-side and lower-side cell groups to the normal path when the filter circuit is of the single RC type according to the fourth embodiment; FIG. 10 is a diagram showing connection paths when the objects to be measured are the unit cells I1 and I13; A diagram showing connection paths when the objects to be measured are the unit cells I2 and I14. A diagram showing a connection path when the measurement objects are the unit cells I12 and I24. A diagram showing a connection path when the object to be measured is the unit cell I25. FIG. 11 is a diagram showing a control sequence for connecting each unit cell of the upper side and lower side cell groups to the diagnosis path with two AFE circuits when the filter circuit is of the single RC type according to the fifth embodiment; FIG. 10 is a diagram showing connection paths when the objects to be measured are the unit cells I1 and I13; A diagram showing connection paths when the objects to be measured are the unit cells I2 and I14. A diagram showing a connection path when the measurement objects are the unit cells I12 and I24. A diagram showing a connection path when the object to be measured is the unit cell I25. FIG. 10 is a diagram showing a connection configuration for measuring the offset voltages of the upper side and lower side AFE circuits according to the sixth embodiment; A diagram showing a seventh embodiment, in which two battery monitoring devices are connected to an assembled battery composed of 50 unit cells via a filter circuit group. The eighth embodiment, showing a normal path and a diagnostic path when the filter circuit is of π type. A diagram showing a normal path and a diagnostic path when the filter circuit is an independent RC type Diagram showing the normal path and diagnosis path when the filter circuit is ground type

(First embodiment)
As shown in FIG. 1, the assembled battery 1 is configured by, for example, connecting 25 unit cells I1 to I25 in series. The unit cells I13 to I25 are divided into two cell groups as an upper cell group 1U. A filter circuit is connected to each of the unit cells I1 to I25, which is shown as one filter circuit group 2 in FIG.

Terminals V0 to V25 and S1 to S26 corresponding to the unit cells I1 to I25 are arranged on the right side of the filter circuit group 2 in the figure. The connection relationship between the terminals V and S and the unit cells conforms to FIGS. The high potential terminal of the unit cell corresponds to the first terminal, and the low potential terminal corresponds to the second terminal.

Upper and lower AFE (Analog Front End) circuits 7U and 7D are provided corresponding to upper cell group 1U and lower cell group 1D, respectively, and are connected to A/D converters 8U and 8D and level shifters (not shown). etc. is built in. Between the filter circuit group 2 and the AFE circuits 7U and 7D, a multiplexer 4, a division wiring section 5 and a polarity reversing switch section 6 are arranged.

One ends of the switch elements 3 (V0) to 3 (S26) constituting the multiplexer 4 are connected to the 52 terminals V0 to V25 and S1 to S26, respectively. The switch element 3 is, for example, an N-channel MOSFET. Since the numbers of cells in the lower cell group 1D and the upper cell group 1U are 12 and 13, respectively, the switching element 3 has a withstand voltage corresponding to the series voltage of those cells.

The divided wiring portion 5 is divided into an upper wiring portion 5U and a lower wiring portion 5D. These wiring portions 5U and 5D are each composed of four wirings VO, VE, SE and SO, and each wiring is connected to the switch element 3 of the multiplexer 4 corresponding to each terminal as follows.
Wiring Terminal VO V odd number VE V even number SO S odd number SE S even number

For example, the switch element 3 (V1) whose one end is connected to the terminal V1 has the other end connected to the wiring VO, and the other end of the switch element 3 (S1) whose one end is connected to the terminal S1 is connected to the wiring SO. there is The other end of the switch element 3 (S26), one end of which is connected to the terminal S26, is connected to the wire SE, and the other end of the switch element 3 (V24), one end of which is connected to the terminal V24, is connected to the wire VE. As for the terminals S13 and V12, the switch elements 3 (S13U) and 3 (V12U) whose other ends are connected to the upper wiring section 5U, and the switch element 3 (S13U) and 3 (V12U) whose other ends are connected to the lower wiring section 5D S13D) and 3 (V12D). Of these, in FIG. 1, only switch elements 3 (S13U) and 3 (S13D) are denoted by reference numerals for convenience of illustration.

The polarity reversal switch section 6 consists of six polarity reversal switches 6 (U1 to U3, D1 to D3), and each switch 6 (U1 to U3, D1 to D3) has four switch elements 9 (1 to 4). It is symmetrically constructed as a four-terminal switch used. The switch element 9 is, for example, an N-channel MOSFET. An input terminal IN(+) of the switch 6 is connected to one end of the switch elements 9(1) and 9(2), and an input terminal IN(-) of the switch elements 9(3) and 9(4) is connected. one end is connected. The output terminal OUT(+) of the switch 6 is connected to the other ends of the switch elements 9(1) and 9(3), and the output terminal OUT(-) is connected to the switch elements 9(2) and 9(4). is connected.

The connection relationship between each wiring and the input terminals I(+) and I(-) of the polarity reversal switch 6 is as follows.
Wiring Polarity reversal switch SO, SE 6 (U1)
VO, VE 6 (U2)
SO, SE 6 (U3)
VO, VE 6 (D1)
VO, VE 6 (D2)
SO, SE 6 (D3)
The polarity reversing switches 6 (U2), 6 (U1), and 6 (U3) correspond to the upper side first to third switch groups, and the polarity reversing switches 6 (D2), 6 (D3), and 6 (D1) correspond to the lower side switches. It corresponds to the side first to third switch groups.

The input terminals IN(+) and IN(-) of the AFE circuit 7U are connected to the output terminals OUT(+) and OUT(-) of the polarity reversing switches 6(U1), 6(U2) and 6(D1). ing. The input terminals IN(+) and IN(-) of the AFE circuit 7D are connected to the output terminals OUT(+) and OUT(-) of the polarity reversing switches 6(U3), 6(D2) and 6(D3). ing. A control circuit 10 composed of a logic circuit controls on/off of the switching elements 3 and 9 that constitute the multiplexer 4 and the polarity reversing switch section 6 . In the above, the battery monitoring device 11 is configured by removing the assembled battery 1 and the filter circuit group 2 .

Next, the operation of this embodiment will be described.
<π-type/ground-type filter circuit: normal path, diagnostic path parallel measurement>
In this embodiment, when the type of the filter circuit group 2 is the π type or the ground type, the AFE circuit 7D side measures the voltage of the normal path for one unit cell in parallel with the measurement of the voltage on the AFE circuit 7D side. The case of measuring the voltage by the diagnostic path is shown.

2, for the unit cells I1 to I12 of the lower cell group 1D, the terminals Vn and Vn-1 are sequentially connected to the differential input terminals of the AFE circuit 7U, and at the same time the terminal Sn+1 is sequentially connected to the differential input terminals of the AFE circuit 7D. , Sn are shown. In this case, n=1-12.

In FIG. 3, for the unit cells I13 to I25 of the upper cell group 1U, the terminals Vn and Vn-1 are sequentially connected to the differential input terminals of the AFE circuit 7U, and at the same time the terminal Sn+1 is sequentially connected to the differential input terminals of the AFE circuit 7D. , Sn are shown. In this case, n=13-25.

In FIG. 4 and subsequent figures, illustration of the control circuit 10 is omitted, and thick lines are superimposed on the paths in which the switch elements are turned on. Light bold lines indicate normal pathways and dark bold lines indicate diagnostic pathways. FIG. 4 shows a connection path when the object to be measured is the unit cell I1. At this time, the normal path; connection between the terminals V1 and V0 and the AFE circuit 7U is made through the polarity reversing switch 6 (D1). Also, the diagnosis path; terminals S2 and S1 are connected to the AFE circuit 7D via the polarity reversal switch 6 (D3).

4 only in FIG. 4 to avoid complication of the drawing, the switch element 9 constituting the polarity reversal switch section 6, which is not related to the formation of the normal path or the diagnostic path, is actually in a floating state. In order to avoid this, the switch elements 3 connected to the terminals S14, V13, S13 and V12 in the multiplexer 4 are also turned on. In this case, by synchronously switching the switch elements 3 of the multiplexers 4 corresponding to the cell groups 1D and 1U, respectively, the voltages applied to the polarity inversion switches 6 on the lower side and the upper side are reduced. There is no need to use a switch element with a high withstand voltage for each of the cell groups 1D and 1U.

FIG. 5 shows the connection path when the object to be measured is the unit cell I12. At this time, the normal path; the connection between the terminals V12 and V11 and the AFE circuit 7U is made by reversing the polarity via the polarity reversing switch 6 (D1). Further, the diagnostic path; terminals S13 and S12 are connected to the AFE circuit 7D by reversing the polarity via the polarity reversing switch 6 (D3).

FIG. 6 shows a connection path when the object to be measured is the unit cell I13. At this time, normal path; terminals V13, V12 and AFE circuit 7U are connected via polarity reversal switch 6 (U2). Also, the diagnosis path; terminals S14, S13 and the AFE circuit 7D are connected via the polarity reversing switch 6 (U3).

FIG. 7 shows a connection path when the object to be measured is the unit cell I24. At this time, the normal path; connection between the terminals V24 and V23 and the AFE circuit 7U is performed by reversing the polarity via the polarity reversing switch 6 (U2). Further, the diagnostic path; terminals S25 and S24 are connected to the AFE circuit 7D by reversing the polarity via the polarity reversing switch 6 (U3).

FIG. 8 shows a connection path when the object to be measured is the unit cell I25. At this time, the normal path; connection between the terminals V25 and V24 and the AFE circuit 7U is made through the polarity reversing switch 6 (U2). Also, the diagnosis path; terminals S26 and S25 are connected to the AFE circuit 7D via the polarity reversal switch 6 (U3).

As described above, according to the present embodiment, the 25 unit cells I1 to I25 are grouped into the upper cell group 1U and the lower cell group 1D. to connect. A battery monitoring device 11 is provided with an upper side AFE circuit 7U and a lower side AFE circuit 7D containing A/D converters 8U and 8D. A plurality of multiplexers 4 each having one end connected to the terminal V and terminal S of each unit cell and the other end connected to any one of the wirings VO, VE, SO and SE in the upper and lower wiring portions 5U and 5D. is composed of the switch element 3 of

Six polarity reversing switches 6 (U1) to 6 each composed of a plurality of switch elements 9 are provided between the divided wiring section 5 and the differential input terminals IN(+) and IN(-) of the AFE circuits 7U and 7D. Place (D3). As a result, voltages can be measured independently in the upper cell group 1U and the lower cell group 1D. Further, by arranging the divided wiring section 5 between the multiplexer 4 and each polarity reversing switch 6 and using it together with each polarity reversing switch 6, it is possible to suppress an increase in the number of switch elements 3 constituting the multiplexer 4. FIG.

In this case, by providing an upper-side polarity reversal switch 6 (U3) connectable to the AFE circuit 7D and a lower-side polarity reversal switch 6 (D1) connectable to the AFE circuit 7U, The connections between the cell groups 1U and 1D and the AFE circuits 7U and 7D can be switched more flexibly, enabling simultaneous detection of the normal path and the diagnostic path.

Then, the control circuit 10 controls the multiplexer 4 and the polarity reversing switch 6 to detect a failure in the diagnostic path for detecting the voltage of each unit cell I1 to I25 and the path from the assembled battery 1 to the AFE circuit 7. When the voltage is generated, the normal path is switched to detect a voltage that is lower than the voltage. That is, when the type of the filter circuit group 2 is π type or ground type, failure detection can be performed by comparing the voltages measured by the respective paths.
Note that failures detected by comparing the voltage measured in the normal path and the voltage measured in the diagnostic path are not limited to leaks in the filter capacitors, but also multiplexer 4 failures, short-circuit failures between terminals, etc. It is also possible to deal with

(Second embodiment)
Hereinafter, the same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted, and different parts will be described.
<π-type/ground-type filter circuit: upper side, lower side normal path parallel measurement>
As shown in FIG. 9, in the second embodiment, when the filter circuit group 2 is also of the π type or ground type, the AFE circuit 7D side measures the voltage of the lower cell group 1D through the normal path. In parallel, a case is shown in which the AFE circuit 7U side measures the voltage of the upper cell group 1U through the normal path. The upper terminals Vn and Vn-1 (n=13 to 25) are connected to the differential input terminals of the AFE circuit 7U, and the lower terminals Vn and Vn-1 (n=13 to 25) are connected to the differential input terminals of the AFE circuit 7D. = 1 to 12). A thin thick line indicates a normal route on the upper side, and a thick thick line indicates a normal route on the lower side. At this time, as shown in the figure, the switch elements 3 of the multiplexer 4 corresponding to the lower cell group 1D and the upper cell group 1U are switched in synchronization.

FIG. 10 shows connection paths when the objects to be measured are the unit cells I1 and I13. At this time, the normal path; connection between the terminals V1 and V0 and the AFE circuit 7D is made through the polarity reversing switch 6 (D2). Also, normal path; terminals V13, V12 and AFE circuit 7U are connected through polarity reversal switch 6 (U2).

FIG. 11 shows connection paths when the objects to be measured are the unit cells I2 and I14. At this time, the normal path; connection between the terminals V2 and V1 and the AFE circuit 7D is performed by reversing the polarity via the polarity reversing switch 6 (D2). Also, the connection between the terminals V14, V13 and the AFE circuit 7U on the normal path is made by reversing the polarity via the polarity reversing switch 6 (U2).

FIG. 12 shows the connection paths when the objects to be measured are the unit cells I12 and I24. At this time, the normal path; connection between the terminals V12 and V11 and the AFE circuit 7D is performed by reversing the polarity via the polarity reversing switch 6 (D2). Also, the normal path; the connection between the terminals V24 and V23 and the AFE circuit 7U is made by reversing the polarity via the polarity reversing switch 6 (U2).

FIG. 13 shows a connection path when the object to be measured is the unit cell I25. At this time, the normal path; connection between the terminals V25 and V24 and the AFE circuit 7U is made through the polarity reversing switch 6 (U2).

As described above, according to the second embodiment, when the type of the filter circuit group 2 is the π type or the ground type, the voltages of the upper cell group 1U and the lower cell group 1D are measured in parallel using the normal path. can be done by

(Third embodiment)
<π-type/ground-type filter circuit: upper side, lower side diagnostic path parallel measurement>
As shown in FIG. 14, in the third embodiment, when the filter circuit group 2 is also of the π type or ground type, the AFE circuit 7D side measures the voltage of the lower cell group 1D through the diagnostic path. In parallel, the case of measuring the voltage through the diagnostic path for the upper cell group 1U on the AFE circuit 7U side will be shown. The upper terminals Sn+1 and Sn (n=13 to 25) are connected to the differential input terminals of the AFE circuit 7U, and the lower terminals Sn+1 and Sn (n=1 to 12) are connected to the differential input terminals of the AFE circuit 7D. ). A thin thick line indicates a diagnostic pathway on the upper side, and a thick thick line indicates a diagnostic pathway on the lower side.

FIG. 15 shows connection paths when the objects to be measured are the unit cells I1 and I13. At this time, the diagnosis path; terminals S2 and S1 are connected to the AFE circuit 7D via the polarity reversing switch 6 (D3). Also, the diagnosis path; terminals S14, S13 and the AFE circuit 7U are connected via the polarity reversal switch 6 (U1).

FIG. 16 shows connection paths when the objects to be measured are the unit cells I2 and I14. At this time, the diagnosis path; terminals S3 and S2 are connected to the AFE circuit 7D by reversing the polarity via the polarity reversing switch 6 (D3). Further, the diagnostic path; terminals S15 and S14 are connected to the AFE circuit 7U by reversing the polarity via the polarity reversing switch 6 (U1).

FIG. 17 shows the connection paths when the objects to be measured are the unit cells I12 and I24. At this time, the diagnosis path; terminals S13 and S12 are connected to the AFE circuit 7D by reversing the polarity via the polarity reversing switch 6 (D3). Further, the diagnostic path; terminals S25 and S24 are connected to the AFE circuit 7U by reversing the polarity via the polarity reversing switch 6 (U1).

FIG. 18 shows the connection path when the object to be measured is the unit cell I25. At this time, the diagnosis path; terminals S26 and S25 are connected to the AFE circuit 7U via the polarity reversal switch 6 (U1).

As described above, according to the third embodiment, when the type of the filter circuit group 2 is the π type or the ground type, the voltage measurement through the diagnostic path is performed in parallel for each of the upper cell group 1U and the lower cell group 1D. can be done by

(Fourth embodiment)
<Individual RC type filter circuit: upper side, lower side normal path parallel measurement>
As shown in FIG. 19, in the fourth embodiment, when the filter circuit group 2 is of the single RC type, the AFE circuit 7D side measures the voltage of the lower cell group 1D in parallel with the normal path voltage measurement. , and the AFE circuit 7U side to measure the voltage of the upper cell group 1U through the normal path. Regarding the unit cells I1 to I12 of the lower cell group 1D, the terminals Vn and Sn (n=1 to 12) are sequentially connected to the differential input terminals of the AFE circuit 7D, and at the same time, the terminals are sequentially connected to the differential input terminals of the AFE circuit 7U. Connect Vn and Sn (n=13 to 25). A thin thick line indicates a normal route on the upper side, and a thick thick line indicates a normal route on the lower side.

FIG. 20 shows connection paths when the objects to be measured are the unit cells I1 and I13. At this time, the normal path; connection between the terminals V1, S1 and the AFE circuit 7D is made through the polarity reversing switches 6 (D2), 6 (D3). Also, normal path; terminals V13, S13 and AFE circuit 7U are connected through polarity reversing switches 6 (U2), 6 (U1).

FIG. 21 shows connection paths when the objects to be measured are the unit cells I2 and I14. At this time, the normal path; connection between the terminals V2 and S2 and the AFE circuit 7D is made through the polarity reversing switches 6 (D2) and 6 (D3). Also, normal path; terminals V14, S14 and AFE circuit 7U are connected via polarity reversing switches 6 (U2), 6 (U1).

FIG. 22 shows connection paths when the objects to be measured are the unit cells I12 and I24. At this time, the normal path; connection between the terminals V12, S12 and the AFE circuit 7D is made through the polarity reversing switches 6 (D2), 6 (D3). Also, normal path; terminals V24, S24 and AFE circuit 7U are connected via polarity reversing switches 6 (U2), 6 (U1).

FIG. 23 shows the connection path when the object to be measured is the unit cell I125. At this time, the normal path; connection between the terminals V25, S25 and the AFE circuit 7U is made through the polarity reversing switches 6 (U2), 6 (U1).

As described above, according to the fourth embodiment, when the filter circuit group 2 is of the single RC type, the voltages of the upper cell group 1U and the lower cell group 1D are measured in parallel using the normal path. It can be carried out.

(Fifth embodiment)
<Individual RC type filter circuit: upper side, lower side diagnostic path parallel measurement>
As shown in FIG. 24, in the fifth embodiment, when the filter circuit group 2 is also of the single RC type, the AFE circuit 7D side measures the voltage through the diagnostic path for the lower cell group 1D. , the case where the AFE circuit 7U side measures the voltage through the diagnostic path for the upper cell group 1U. Regarding the unit cells I1 to I12 of the lower cell group 1D, the terminals Sn+1 and Vn-1 (n=1 to 12) are sequentially connected to the differential input terminals of the AFE circuit 7D, and at the same time, to the differential input terminals of the AFE circuit 7U. Terminals Sn+1 and Vn-1 (n=13 to 25) are connected in sequence. A thin thick line indicates a diagnostic pathway on the upper side, and a thick thick line indicates a diagnostic pathway on the lower side.

FIG. 25 shows connection paths when the objects to be measured are the unit cells I1 and I13. At this time, the diagnosis path; terminals S2 and V0 are connected to the AFE circuit 7D via the polarity reversing switches 6 (D3) and 6 (D2). Also, the diagnostic path; terminals S14, V12 and the AFE circuit 7U are connected via the polarity reversing switches 6 (U1), 6 (U2).

FIG. 26 shows connection paths when the objects to be measured are the unit cells I2 and I14. At this time, the diagnosis path; terminals S3, V1 and the AFE circuit 7D are connected via the polarity reversing switches 6 (D3), 6 (D2). Also, the diagnosis path; terminals S15, V13 and the AFE circuit 7U are connected via the polarity reversing switches 6 (U1), 6 (U2).

FIG. 27 shows the connection paths when the objects to be measured are the unit cells I12 and I24. At this time, the diagnosis path; terminals S13, V11 and the AFE circuit 7D are connected via the polarity reversing switches 6 (D3), 6 (D2). Also, the diagnosis path; terminals S25, V23 and the AFE circuit 7U are connected via the polarity reversing switches 6 (U1), 6 (U2).

FIG. 28 shows a connection path when the object to be measured is the unit cell I25. At this time, the diagnosis path; terminals S26, V24 and the AFE circuit 7U are connected via the polarity reversing switches 6 (U1), 6 (U2).

As described above, according to the fifth embodiment, when the type of the filter circuit group 2 is the single RC type, the voltages of the upper cell group 1U and the lower cell group 1D are measured in parallel through the diagnostic path. It can be carried out.

(Sixth embodiment)
<Offset voltage measurement of upper and lower AFE circuits>
In the sixth embodiment, for example, as shown in FIG. 29, the switch elements 9(3) and 9(4) of the polarity reversal switch 6 (D2) are turned on at the same time, and the switch element 9 ( By simultaneously turning on 3) and 9(4), the differential input terminals of the AFE circuits 7D and 7U are short-circuited. By measuring the voltage at this time with the A/D converters 8D and 8U, the input offset voltage Vos of the AFE circuits 7D and 7U can be obtained. By subtracting the offset voltage Vos from the voltage measured after that, the voltage excluding the offset can be obtained.

(Seventh embodiment)
In the seventh embodiment shown in FIG. 30, the upper cell group 1U of the assembled battery 1 in the first embodiment is divided into an upper cell group 1UU and a lower cell group 1UD as follows, and a lower cell group 1D are divided into an upper cell group 1DU and a lower cell group 1DD.
Cell group unit cell 1UU I19-125
1UD I13-I18
1DU I7-I12
1DD I1-I6

A battery monitoring device 11U having two AFE circuits 7UU and 7UD is arranged for the upper cell group 1UU and the lower cell group 1UD, and two AFEs are arranged for the upper cell group 1DU and the lower cell group 1DD. A configuration in which a battery monitoring device 11D including circuits 7DU and 7DD is arranged is shown. In the figure, the type of the filter circuit is π type/ground type, and in the battery monitoring device 11U on the upper side, it is connected to the normal path and diagnostic path of the unit cell I13, and in the battery monitoring device 11D on the lower side, It shows a state in which the unit cell I1 is connected to the normal path and diagnostic path.

(Eighth embodiment)
In the eighth embodiment shown in FIG. 31, when the filter circuit of the filter circuit group 2 is of π type, RC This is the case when the time constants of the filters are set to be equal. At this time, if there is no failure such as leakage, the voltages measured in the normal path and the diagnostic path will be equal, and the path on the side where the failure has occurred will have a lower measured voltage than the other path. . The figure shows a case where leakage occurs in the filter capacitor in the normal path, and a voltage drop of (2ΔV) occurs in the normal path with respect to the cell voltage measured in the diagnostic path. With this configuration, the time constants of the RC filters for disturbance noise are equal between the normal path and the diagnosis path, so that the measurement accuracy can be further improved.

(Other embodiments)
Switch elements are not limited to N-channel MOSFETs.
For example, one of the A/D converters 8D and 8U may be operated in a low-speed high-precision conversion mode, and the other may be operated in a high-speed low-precision conversion mode.
The number of unit cells forming the assembled battery 1 is not limited to 25 pieces.
As described in the first embodiment, in order to prevent the switch element 9 constituting the polarity reversal switch section 6, which is not related to the formation of the normal path or the diagnostic path, from being in a floating state, the switch element 9 is connected to the The switch element 3 of the multiplexer 4 that is present may be appropriately turned on.
The polarity reversal switch 6 (U3) is connected to the wirings VO and VE instead of the wirings SO and SE of the upper wiring section 5U, and the polarity reversing switch 6 (D1) is connected to the wirings VO and VE of the lower wiring section 5D. Alternatively, wirings SO and SE may be connected.
Although the present disclosure has been described with reference to examples, it is understood that the present disclosure is not limited to such examples or structures. The present disclosure also includes various modifications and modifications within the equivalent range. In addition, various combinations and configurations, as well as other combinations and configurations, including single elements, more, or less, are within the scope and spirit of this disclosure.

In the drawings, 1 is an assembled battery, 1U is an upper cell group, 1D is a lower cell group, 2 is a filter circuit group, 3 is a switch element, 4 is a multiplexer, 5 is a divided wiring part, 6 (U1 to U3, D1 . . . D3) denote polarity reversal switch units 6, 7U and 7D denote AFE circuits, 8U and 8D denote A/D converters, 9 denote switch elements, and 10 denotes a control circuit.

Claims (9)

A plurality of unit cells (I1 to I25) are grouped into upper cell groups (1U, 1UU, 1DU) and lower cell groups (1D, 1UD, 1DD) through filter circuit groups (2). connected and
an upper odd-numbered first wiring and an upper even-numbered first wiring and an upper odd-numbered second wiring and an upper even-numbered second wiring provided corresponding to the upper-side cell group;
a lower odd-numbered first wiring, a lower-side even-numbered first wiring, a lower-side odd-numbered second wiring, and a lower-side even-numbered second wiring provided corresponding to the lower-side cell group, one end of which is on the first terminal side of each unit cell; A multiplexer (4) comprising a plurality of switch elements (3) each connected to a second terminal side and the other end connected to any one of the odd first wiring, the even first wiring, the odd second wiring, and the even second wiring )When,
upper side front-end circuits (7U, 7UU, 7DU) and lower side front-end circuits (7D, 7UD, 7DD) containing A/D converters (8U, 8D);
A plurality of wirings arranged between the higher-order odd-numbered first wiring and the higher-order even-numbered first wiring and the differential input terminals of the higher-order front-end circuit, and capable of reversing the input polarity to the differential input terminals. A higher-order side first switch group (6 (U2)) consisting of switch elements of
A plurality of wirings arranged between the higher-order odd-numbered second wiring and the higher-order even-numbered second wiring and the differential input terminals of the higher-order front-end circuit, and capable of inverting the input polarity to the differential input terminals. A higher-order side second switch group (6 (U1)) consisting of switch elements of
arranged between the upper odd-numbered second wiring and the upper even-numbered second wiring or the upper-order odd-numbered first wiring and the upper even-numbered first wiring and differential input terminals of the lower-side front-end circuit; an upper-side third switch group (6 (U3)) composed of a plurality of switch elements capable of reversing the input polarity to the differential input terminals;
A plurality of wirings arranged between the lower-side odd-numbered first wiring and the lower-side even-numbered first wiring and the differential input terminals of the lower-side front-end circuit, and capable of reversing the input polarity to the differential input terminals. a lower-side first switch group (6 (D2)) consisting of switch elements of
A plurality of wirings arranged between the lower odd-numbered second wiring and the lower even-numbered second wiring and the differential input terminals of the lower front-end circuit, and capable of reversing the input polarity to the differential input terminals. a lower-side second switch group (6 (D3)) consisting of switch elements of
arranged between the lower odd first wiring and the lower even first wiring or the lower odd second wiring and the lower even second wiring and differential input terminals of the upper front end circuit; A battery monitoring device comprising a lower side third switch group (6(D1)) consisting of a plurality of switch elements capable of reversing the input polarity to the differential input terminals. A normal path for detecting the voltage of each unit cell by controlling the multiplexer, the first to third switch groups on the upper side and the first to third switch groups on the lower side, and a front end circuit from the unit cell 2. A battery monitoring device according to claim 1, comprising a control circuit (10) for switching between a diagnostic path for detecting a voltage for comparison with said voltage when detecting a failure in the path to. the control circuit controls one of the two front-end circuits to detect the voltage of the unit cell of the upper cell group through the normal path;
3. The battery monitoring device according to claim 2, wherein the other of said two front-end circuits is controlled to detect the voltage of the unit cell of said lower cell group through said normal path. the control circuit controls one of the two front-end circuits to detect the voltage of the unit cell of the upper cell group through the diagnostic path;
4. The battery monitoring device according to claim 2, wherein the other of the two front-end circuits is controlled to detect the voltage of the unit cell of the lower cell group through the diagnostic path. the control circuit controls one of the two front-end circuits to detect the voltages of the unit cells of the upper-side and lower-side cell groups through the normal path;
5. The battery monitoring device according to any one of claims 2 to 4, wherein the other of the two front-end circuits is controlled to detect the voltages of the unit cells of the upper-side and lower-side cell groups through the diagnosis path. . 3. From claim 2, wherein in the multiplexer, the control circuit simultaneously turns on switch elements connected to one of the unit cells belonging to the upper cell group and one of the unit cells belonging to the lower cell group. 6. The battery monitoring device according to any one of 5. The control circuit is of a semi-common type in which the filter circuit has a semi-common detection terminal for detecting the voltage of each unit cell and an equalization terminal for equalizing the voltage of each unit cell. 7. The battery according to any one of claims 2 to 6, wherein the normal path and the diagnosis path can be switched in both the battery of the separated type in which the detection terminal and the equalization terminal are separated. surveillance equipment. A filter circuit group in which the filter circuit is a separate type,
8. The battery monitoring device according to claim 7, wherein the time constant of said filter circuit is set to be the same between said detection terminals and between said equalization terminals. The battery monitoring device according to any one of claims 2 to 8, wherein the control circuit makes it possible to detect the offset voltage of the A/D converter by short-circuiting the differential input terminals of the front-end circuit. .

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