JP2021191011A - Battery monitoring device - Google Patents

Battery monitoring device Download PDF

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JP2021191011A
JP2021191011A JP2020090510A JP2020090510A JP2021191011A JP 2021191011 A JP2021191011 A JP 2021191011A JP 2020090510 A JP2020090510 A JP 2020090510A JP 2020090510 A JP2020090510 A JP 2020090510A JP 2021191011 A JP2021191011 A JP 2021191011A
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Prior art keywords
equalization
circuit
switch
block
battery
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誠人 塚原
Masato Tsukahara
輝 川本
Teru Kawamoto
幸拓 朝長
Yukihiro Tomonaga
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Denso Corp
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Denso Corp
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Priority to JP2020090510A priority Critical patent/JP2021191011A/en
Priority to PCT/JP2021/017372 priority patent/WO2021241153A1/en
Publication of JP2021191011A publication Critical patent/JP2021191011A/en
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/44—Methods for charging or discharging
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/48—Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/02—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from ac mains by converters
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Abstract

To detect a failure in a cell equalization circuit or block equalization circuit, and continue a normal equalization operation.SOLUTION: A failure detection circuit 7 makes a failure determination by comparing a voltage value to be applied to an equalization switch 13 that a cell equalization circuit 5 or a block equalization circuit 6 has, with a prescribed threshold in accordance with the ON/OFF state of the switch 13. When a failure in the equalization switch 13 in one of the equalization circuits 5 and 6 is determined, a control circuit 8 switches a path of an equalization current that flows to perform equalization in accordance with the state of the failure. Accordingly, the equalization is continued.SELECTED DRAWING: Figure 2

Description

本発明は、組電池を構成する複数の電池ブロック，及びその電池ブロックを構成する複数の電池セルについて均等化制御を行う装置に関する。 The present invention relates to a plurality of battery blocks constituting an assembled battery and a device for performing equalization control on a plurality of battery cells constituting the battery block.

ハイブリッド車両や電気自動車には、動力源であるモータに電力を供給するための電池ユニットが搭載されている。この電池ユニットは、複数の電池ブロックを直列に接続して構成されており、各電池ブロックは、複数の電池セルを直列に接続して構成される。ここで、各電池セルには内部抵抗や容量にバラつきがあり、これに起因して各電池セルの電圧にバラつきが生じる Hybrid vehicles and electric vehicles are equipped with a battery unit for supplying electric power to a motor that is a power source. This battery unit is configured by connecting a plurality of battery blocks in series, and each battery block is configured by connecting a plurality of battery cells in series. Here, there are variations in the internal resistance and capacity of each battery cell, which causes variations in the voltage of each battery cell.

そこで、各電池セル間の電圧のバラつきを解消するため、電池ユニットに付随する監視装置には、電圧の均等化を行うセル均等化回路が搭載されている。また、各電池セルのバラつきは、各電池ブロック間の電圧のバラつきも引き起こす。しかし、各電池ブロック間の電圧のバラつきまでもセル均等化回路だけで解消しようとすると、効率が悪く時間がかかる。そこで、各電池ブロック間の電圧を均等化するためのブロック均等化回路を別途設けて、ブロック間の電圧を効率よく均等化することも行われている。 Therefore, in order to eliminate the voltage variation between the battery cells, the monitoring device attached to the battery unit is equipped with a cell equalization circuit for equalizing the voltage. In addition, the variation of each battery cell also causes the variation of the voltage between each battery block. However, if the voltage variation between the battery blocks is to be eliminated only by the cell equalization circuit, the efficiency is low and it takes time. Therefore, a block equalization circuit for equalizing the voltage between the battery blocks is separately provided to efficiently equalize the voltage between the blocks.

特開２００６−２５４５３５号公報Japanese Unexamined Patent Publication No. 2006-254535

例えば従来の均等化制御では、ブロック電圧のバラつきの程度に応じて電圧が低下しているブロックを特定すると、そのブロックの均等化を停止して放電電流を低減することで過放電状態に至ることを回避している。 For example, in the conventional equalization control, when a block whose voltage is decreasing is specified according to the degree of variation in the block voltage, the equalization of the block is stopped and the discharge current is reduced to reach an over-discharged state. Is avoided.

しかしながら、従来の構成では、均等化回路が備えているセルを放電させるための均等化スイッチに、例えばＯＮ状態で固着する故障が発生し、そのまま通常の均等化動作を行い続けると電池ブロックが過放電になるおそれがある。 However, in the conventional configuration, a failure occurs in the equalization switch for discharging the cell provided in the equalization circuit, for example, in the ON state, and if the normal equalization operation is continued as it is, the battery block becomes excessive. There is a risk of discharge.

本発明は上記事情に鑑みてなされたものであり、その目的は、セル均等化回路又はブロック均等化回路の故障を検知して、正常な均等化動作を継続できる電池監視装置を提供することにある。 The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a battery monitoring device capable of detecting a failure of a cell equalization circuit or a block equalization circuit and continuing a normal equalization operation. be.

請求項１記載の電池監視装置によれば、セル均等化回路は、各電池ブロック内の電池セル間の電圧を均等化する均等化スイッチを有し、ブロック均等化回路は、各電池ブロック間の電圧を均等化する均等化スイッチを有する。故障検出回路は、均等化スイッチのＯＮ／ＯＦＦ状態に応じて印加される電圧値又は流れる電流値を所定の値と比較して、均等化スイッチの故障判定を行う。 According to the battery monitoring device according to claim 1, the cell equalization circuit has an equalization switch for equalizing the voltage between the battery cells in each battery block, and the block equalization circuit is between the battery blocks. It has an equalization switch that equalizes the voltage. The failure detection circuit compares the voltage value applied or the flowing current value according to the ON / OFF state of the equalization switch with a predetermined value, and determines the failure of the equalization switch.

制御回路は、均等化スイッチのＯＮ／ＯＦＦを制御して各電池セル間及び各電池ブロック間の均等化制御を行うと共に、均等化回路の一方について均等化スイッチの故障が判定されると、その故障の状態に応じて均等化を行う際に流れる均等化電流の経路を切り替えて、均等化を継続する。 The control circuit controls ON / OFF of the equalization switch to perform equalization control between each battery cell and each battery block, and when a failure of the equalization switch is determined for one of the equalization circuits, the control circuit performs equalization control. The path of the equalization current flowing when performing equalization according to the state of failure is switched to continue equalization.

具体的には、制御回路は、請求項２記載の電池監視装置のように、ブロック均等化回路の均等化スイッチが故障と判定されるとセル均等化回路により均等化を行うように切り替え、また請求項３記載の電池監視装置のように、セル均等化回路の均等化スイッチが故障と判定されると、故障が発生したセル均等化回路に替えて、当該セル均等化回路が属する電池ブロックのブロック均等化回路により均等化を行うように切り替える。 Specifically, the control circuit is switched so as to perform equalization by the cell equalization circuit when the equalization switch of the block equalization circuit is determined to be a failure, as in the battery monitoring device according to claim 2. When the cell equalization switch of the cell equalization circuit is determined to be defective as in the battery monitoring device according to claim 3, the battery block to which the cell equalization circuit belongs is replaced with the cell equalization circuit in which the failure has occurred. Switch to equalize by the block equalization circuit.

このように構成すれば、ブロック又はセル均等化回路の一方が有する均等化スイッチが故障しても、他方の均等化回路によりブロック又はセルの均等化を代替させて継続することができる。したがって、冗長性を向上させることができる。 With this configuration, even if the equalization switch of one of the block or cell equalization circuit fails, the equalization circuit of the other can substitute for the equalization of the block or cell and continue. Therefore, redundancy can be improved.

第１実施形態であり、電池監視装置の構成を示す機能ブロック図A functional block diagram according to the first embodiment and showing a configuration of a battery monitoring device. ブロック均等化回路の構成を示す機能ブロック図Functional block diagram showing the configuration of the block equalization circuit ブロック均等化回路による均等化をセル均等化回路に代替させる処理を示すフローチャートA flowchart showing a process of substituting a cell equalization circuit for equalization by a block equalization circuit. セル均等化回路による均等化をブロック均等化回路に代替させる処理を示すフローチャートA flowchart showing a process of substituting a block equalization circuit for equalization by a cell equalization circuit. 第２実施形態であり、ブロック均等化回路の構成を示す機能ブロック図The second embodiment is a functional block diagram showing a configuration of a block equalization circuit. 第３実施形態であり、ブロック均等化回路の構成を示す機能ブロック図The third embodiment is a functional block diagram showing a configuration of a block equalization circuit. 第４実施形態であり、ブロック均等化回路の構成を示す機能ブロック図The fourth embodiment is a functional block diagram showing a configuration of a block equalization circuit.

（第１実施形態）
以下、第１実施形態について説明する。図１に示すように、電池ユニット１は、複数の電池ブロックＢ１〜Ｂｍを直列に接続して構成され、各電池ブロックＢは、複数の単位電池セルＣ１〜Ｃｎを直列に接続して構成されている。本実施形態の電池監視装置２は、各電池ブロックＢ１〜Ｂｎにそれぞれ接続される電池監視ユニット３（１）〜３（ｎ）と、これらの電池監視ユニット３を統括的に制御するマイクロコンピュータ４とを備えている。 (First Embodiment)
Hereinafter, the first embodiment will be described. As shown in FIG. 1, the battery unit 1 is configured by connecting a plurality of battery blocks B1 to Bm in series, and each battery block B is configured by connecting a plurality of unit battery cells C1 to Cn in series. ing. The battery monitoring device 2 of the present embodiment includes the battery monitoring units 3 (1) to 3 (n) connected to the battery blocks B1 to Bn, respectively, and the microcomputer 4 that collectively controls these battery monitoring units 3. And have.

電池監視ユニット３は、各電池セルＣ１〜Ｃｎ間の電圧を均等化するセル均等化回路５，電池ブロックＢ１〜Ｂｎ間の電圧を均等化するブロック均等化回路６，セル均等化回路５及びブロック均等化回路６の故障を判定する故障検出回路７，マイコン４との間で情報を送受信し、均等化回路５及び６のＯＮ／ＯＦＦを制御する制御回路８を備えている。 The battery monitoring unit 3 includes a cell equalization circuit that equalizes the voltage between the battery cells C1 to Cn 5, a block equalization circuit that equalizes the voltage between the battery blocks B1 to Bn 6, a cell equalization circuit 5, and a block. A control circuit 8 for transmitting and receiving information to and from the failure detection circuit 7 for determining the failure of the equalization circuit 6 and the microcomputer 4 and controlling ON / OFF of the equalization circuit 5 and 6 is provided.

尚、セル均等化回路５及びブロック均等化回路６の構成は同一なので、同一の回路素子には同一の符号を付しており、以下ではブロック均等化回路６について説明する。図２に示すように、ブロック均等化回路６は、電池ブロックＢの正側端子と負側端子との間に接続される、ヒューズ１１，電流制限抵抗１２及び均等化スイッチ１３の直列回路を備えている。ヒューズ１１には、短絡スイッチ１４が並列に接続されている。均等化スイッチ１３及び短絡スイッチ１４のＯＮ／ＯＦＦは、マイコン４により制御回路８を介して制御される。 Since the cell equalization circuit 5 and the block equalization circuit 6 have the same configuration, the same circuit elements are designated by the same reference numerals, and the block equalization circuit 6 will be described below. As shown in FIG. 2, the block equalization circuit 6 includes a series circuit of a fuse 11, a current limiting resistor 12, and an equalization switch 13 connected between the positive terminal and the negative terminal of the battery block B. ing. A short-circuit switch 14 is connected in parallel to the fuse 11. ON / OFF of the equalization switch 13 and the short-circuit switch 14 is controlled by the microcomputer 4 via the control circuit 8.

電池ブロックＢ間の電圧を均等化する際には、マイコン４が制御回路８へ均等化を指示する命令を出力し、その命令を受信した制御回路８が均等化スイッチ１３をＯＮにする。均等化スイッチ１３は、例えばＮチャネルＭＯＳＦＥＴであり、そのドレイン及びソースをそれぞれ端子Ｖｏｕｔ−Ｖｇとし、これらは故障検出回路７の入力端子に接続されている。故障検出回路７は、各端子Ｖｏｕｔ，Ｖｇ間の電圧をＡ／Ｄ変換して読み込むと、所定の閾値と比較して均等化スイッチ１３の故障判定を行う。故障判定の結果は、制御回路８よりマイコン４に出力される。所定の閾値は、例えば電池ブロックＢの端子電圧の１／２程度に設定する。 When equalizing the voltage between the battery blocks B, the microcomputer 4 outputs an instruction instructing equalization to the control circuit 8, and the control circuit 8 receiving the instruction turns on the equalization switch 13. The equalization switch 13 is, for example, an N-channel MOSFET, and its drain and source are terminals Vout-Vg, respectively, and these are connected to the input terminal of the failure detection circuit 7. When the failure detection circuit 7 A / D-converts the voltage between each terminal Vout and Vg and reads it, the failure detection circuit 7 determines the failure of the equalization switch 13 by comparing with a predetermined threshold value. The result of the failure determination is output from the control circuit 8 to the microcomputer 4. The predetermined threshold value is set to, for example, about ½ of the terminal voltage of the battery block B.

具体的には、均等化スイッチ１３が正常であれば、制御回路８がＯＮにすれば当該スイッチ１３は短絡するので、端子Ｖｏｕｔ−Ｖｇ間の電圧は閾値よりも低くなり、故障検出回路７によりＬｏと識別される。一方、均等化スイッチ１３がＯＦＦ固着状態で故障しており、制御回路８がＯＮにしてもＯＦＦのままであれば、端子Ｖｏｕｔ−Ｖｇ間には電池ブロックＢの端子電圧が印加されて閾値よりも高くなり、故障検出回路７によりＨｉと識別されるので、ＯＦＦ固着で故障していると特定できる。 Specifically, if the equalization switch 13 is normal, if the control circuit 8 is turned on, the switch 13 is short-circuited, so that the voltage between the terminals Vout and Vg becomes lower than the threshold value, and the failure detection circuit 7 causes the switch 13 to be short-circuited. Identified as Lo. On the other hand, if the equalization switch 13 is out of order in the OFF fixed state and remains OFF even if the control circuit 8 is turned ON, the terminal voltage of the battery block B is applied between the terminals Vout and Vg, and the terminal voltage is higher than the threshold value. Is also high, and since it is identified as Hi by the failure detection circuit 7, it can be identified that the failure is caused by the OFF sticking.

また、制御回路８が均等化スイッチ１３をＯＦＦにしていれば、上述のように端子Ｖｏｕｔ−Ｖｇ間には電池ブロックＢの端子電圧が印加されているので、故障検出回路７ではＨｉと識別される。一方、均等化スイッチ１３がＯＮ固着状態で故障しており、制御回路８がＯＦＦにしていてもＯＮのままであれば故障検出回路７ではＬｏと識別され、ＯＮ固着で故障していると特定できる。 Further, if the control circuit 8 turns off the equalization switch 13, the terminal voltage of the battery block B is applied between the terminals Vout and Vg as described above, so that it is identified as Hi in the failure detection circuit 7. To. On the other hand, if the equalization switch 13 has failed in the ON stuck state and remains ON even if the control circuit 8 is turned OFF, it is identified as Lo in the failure detection circuit 7 and it is specified that the failure is caused by the ON sticking. can.

短絡スイッチ１４は、通常動作時にはＯＦＦにされ、均等化スイッチ１３がＯＮした際に流れる放電電流を、電流制限抵抗１２に流して制限する。短絡スイッチ１４がＯＮされると、均等化スイッチ１３がＯＮした際に放電電流が流れてヒューズ１１が溶断し、電流経路が遮断される。 The short-circuit switch 14 is turned off during normal operation, and the discharge current flowing when the equalization switch 13 is turned on is limited by flowing through the current limiting resistor 12. When the short-circuit switch 14 is turned on, a discharge current flows when the equalization switch 13 is turned on, the fuse 11 is blown, and the current path is cut off.

次に均等化スイッチ１３が故障した際の均等化回路５，６間の切り替えについて説明する。図３は、下記の切り替え処理を示すフローチャートである。
＜ブロック均等化回路６内の均等化スイッチ１３がＯＦＦ固着した場合＞
この場合、電池ブロックＢからブロック均等化回路６に電流が流れる経路が遮断される。マイコン４は、制御回路８から上記のＯＦＦ固着故障の判定結果を受け取ると（Ｓ１，Ｓ２；ＯＦＦ固着）、セル均等化回路５のみで均等化を行うための命令を出力する。例えば、ブロックＢ１に接続されるブロック均等化回路６がＯＦＦ固着した場合、先ずブロックＢ１のブロック電圧，つまり単位電池セルＣ１の正極とＣｎの負極間の電圧を検出し（Ｓ３）、ブロックＢ２〜Ｂｎのブロック電圧と比較する。その結果、ブロックＢ１を放電する必要があれば（Ｓ４；ＹＥＳ）、マイコン４がブロックＢ１の放電量を計算し、制御回路８がセル均等化回路５（１）〜５（ｎ）の均等化スイッチ１３のＯＮ/ＯＦＦを制御して、マイコン４により計算された放電量に相当する均等化電流を放電する（Ｓ５）。この時、単位電池セルＣ１〜Ｃｎそれぞれの放電量が均一となるように、各単位電池セルＣ１〜Ｃｎの端子電圧を検出しながら均等化を行う。 Next, switching between the equalization circuits 5 and 6 when the equalization switch 13 fails will be described. FIG. 3 is a flowchart showing the following switching process.
<When the equalization switch 13 in the block equalization circuit 6 is fixed to OFF>
In this case, the path through which the current flows from the battery block B to the block equalization circuit 6 is cut off. When the microcomputer 4 receives the determination result of the OFF sticking failure from the control circuit 8 (S1, S2; OFF sticking), the microcomputer 4 outputs an instruction for performing equalization only by the cell equalization circuit 5. For example, when the block equalization circuit 6 connected to the block B1 is fixed to OFF, the block voltage of the block B1, that is, the voltage between the positive electrode of the unit battery cell C1 and the negative electrode of Cn is detected (S3), and the blocks B2 to 2 Compare with the block voltage of Bn. As a result, if it is necessary to discharge the block B1 (S4; YES), the microcomputer 4 calculates the discharge amount of the block B1, and the control circuit 8 equalizes the cell equalization circuits 5 (1) to 5 (n). The ON / OFF of the switch 13 is controlled to discharge the equalized current corresponding to the discharge amount calculated by the microcomputer 4 (S5). At this time, equalization is performed while detecting the terminal voltage of each unit battery cell C1 to Cn so that the discharge amount of each of the unit battery cells C1 to Cn becomes uniform.

＜ブロック均等化回路６内の均等化スイッチ１３がＯＮ固着した場合＞
この場合（Ｓ２；ＯＮ固着）、マイコン４が短絡スイッチ１４をＯＮするように命令を出力し、制御回路８は、その命令を受け取ると、ブロック均等化回路６内の短絡スイッチ１４をＯＮにする（Ｓ６）。すると、電流制限抵抗１２が短絡されてヒューズ１１に大電流が流れて溶断し、ブロック均等化回路６に電流が流れなくなる（Ｓ７）。すなわち、上述したブロック均等化回路６内の均等化スイッチ１３がＯＦＦ固着した状態と同様になるため、同様の処置を行うことでセル均等化回路５により均等化を実施するように切り替える（Ｓ３）。 <When the equalization switch 13 in the block equalization circuit 6 is ON and fixed>
In this case (S2; ON fixed), the microcomputer 4 outputs a command to turn on the short-circuit switch 14, and when the control circuit 8 receives the command, the short-circuit switch 14 in the block equalization circuit 6 is turned on. (S6). Then, the current limiting resistor 12 is short-circuited, a large current flows through the fuse 11 and the fuse is blown, and no current flows through the block equalization circuit 6 (S7). That is, since the equalization switch 13 in the block equalization circuit 6 described above is in the same state as the state where the equalization switch 13 is fixed to OFF, the cell equalization circuit 5 is switched to perform equalization by performing the same measures (S3). ..

次にセル均等化回路５内の均等化スイッチ１３が故障した際の動作を説明する。図４は、下記の切り替え処理を示すフローチャートである。
＜セル均等化回路５内の均等化スイッチ１３がＯＦＦ固着した場合＞
例えば、図２に示す単位電池セルＣ１に接続されたセル均等化回路５（１）内の均等化スイッチ１３がＯＦＦ固着で故障すると（Ｓ１１，Ｓ１２；ＯＦＦ固着）、マイコン４がセル均等化回路５（１）以外のセル均等化回路５（２）〜５（ｎ）内の均等化スイッチ１３をＯＮにする命令を出力する（Ｓ１３）。これにより、単位電池セルＣ２〜Ｃｎが短絡されるので、単位電池セルＣ２の正極側から単位電池セルＣｎの負極側までの経路は配線とみなせる（Ｓ１４）。したがって、単位電池セルＣ１の放電は、ブロック均等化回路６内の均等化スイッチ１３のＯＮ/ＯＦF状態を切り替えることで制御される。すなわち、セル均等化回路５内の均等化スイッチ１３がＯＦＦ固着した際には、ブロック均等化回路６内の均等化スイッチ１３のＯＮ／ＯＦＦ制御を行うことで均等化の実施が可能になる（Ｓ１５）。 Next, the operation when the equalization switch 13 in the cell equalization circuit 5 fails will be described. FIG. 4 is a flowchart showing the following switching process.
<When the equalization switch 13 in the cell equalization circuit 5 is fixed to OFF>
For example, if the equalization switch 13 in the cell equalization circuit 5 (1) connected to the unit battery cell C1 shown in FIG. 2 fails due to OFF sticking (S11, S12; OFF sticking), the microcomputer 4 has a cell equalization circuit. An instruction to turn on the equalization switch 13 in the cell equalization circuits 5 (2) to 5 (n) other than 5 (1) is output (S13). As a result, the unit battery cells C2 to Cn are short-circuited, so that the path from the positive electrode side of the unit battery cell C2 to the negative electrode side of the unit battery cell Cn can be regarded as wiring (S14). Therefore, the discharge of the unit battery cell C1 is controlled by switching the ON / OFF state of the equalization switch 13 in the block equalization circuit 6. That is, when the equalization switch 13 in the cell equalization circuit 5 is fixed to OFF, it is possible to carry out equalization by controlling ON / OFF of the equalization switch 13 in the block equalization circuit 6. S15).

＜セル均等化回路５内の均等化スイッチ１３がＯＮ固着した場合＞
この場合（Ｓ１２；ＯＮ固着）、対応するセル均等化回路５内の短絡スイッチ１４をＯＮにすることで（Ｓ１６）電流制限抵抗１２が短絡され、ヒューズ１１が溶断して回路を遮断すれば、均等化スイッチ１３がＯＦＦ固着した状態と同様になる（Ｓ１７）。そこで、ＯＦＦ固着故障と同様の処置を行うことで、セル均等化回路５の代わりにブロック均等化回路６による均等化の実施にと切り替える（Ｓ１３）。 <When the equalization switch 13 in the cell equalization circuit 5 is ON and fixed>
In this case (S12; ON fixed), by turning on the short-circuit switch 14 in the corresponding cell equalization circuit 5, (S16) the current limiting resistor 12 is short-circuited, the fuse 11 is blown, and the circuit is cut off. It is the same as the state where the equalization switch 13 is fixed to OFF (S17). Therefore, by taking the same measures as the OFF sticking failure, it is switched to the implementation of equalization by the block equalization circuit 6 instead of the cell equalization circuit 5 (S13).

以上のように本実施形態によれば、故障検出回路７は、セル均等化回路５又はブロック均等化回路６が有する均等化スイッチ１３のＯＮ／ＯＦＦ状態に応じて、当該スイッチ１３に印加される電圧値を所定の閾値と比較して故障判定を行う。 As described above, according to the present embodiment, the failure detection circuit 7 is applied to the cell equalization circuit 5 or the block equalization circuit 6 according to the ON / OFF state of the equalization switch 13. The failure is determined by comparing the voltage value with a predetermined threshold value.

制御回路８は、均等化回路５又は６の一方について均等化スイッチ１３の故障が判定されると、その故障の状態に応じて均等化を行う際に流れる均等化電流の経路を切り替えて均等化を継続して行う。具体的には、ブロック均等化回路６側の故障が判定されるとセル均等化回路５により均等化を行うように切り替え、セル均等化回路５側に故障が判定されると、そのセル均等化回路５が属する電池ブロックＢのブロック均等化回路６により均等化を行うように切り替える。このように構成すれば、均等化回路５又は６の一方が有する均等化スイッチ１３が故障しても、他方の均等化回路によりセルＣ又はブロックＢの均等化を代替させて継続できるので、従来よりも冗長性が向上する。 When the failure of the equalization switch 13 is determined for one of the equalization circuits 5 or 6, the control circuit 8 switches the path of the equalization current flowing when performing equalization according to the state of the failure to equalize. Continue to do. Specifically, when a failure on the block equalization circuit 6 side is determined, the cell equalization circuit 5 switches to equalization, and when a failure is determined on the cell equalization circuit 5 side, the cell equalization is performed. The block equalization circuit 6 of the battery block B to which the circuit 5 belongs switches to equalize. With this configuration, even if the equalization switch 13 of one of the equalization circuits 5 or 6 fails, the equalization circuit of the other can be used instead of the equalization of the cell C or the block B to continue the equalization. Redundancy is improved.

また、均等化回路５及び６に、並列に接続される電流制限抵抗１２および短絡スイッチ１４と、これらに直列に接続されるヒューズ１１とを備え、制御回路８は、均等化スイッチ１３の故障がＯＮ状態での固着であれば、短絡スイッチ１４をＯＮしてヒューズ１１を溶断させる。これにより、セルＣ又はブロックＢより対応する均等化回路５又は６を遮断して、セルＣ又はブロックＢが過放電状態になることを確実に回避できる。 Further, the equalization circuits 5 and 6 are provided with a current limiting resistor 12 and a short-circuit switch 14 connected in parallel, and a fuse 11 connected in series with them, and the control circuit 8 has a failure of the equalization switch 13. If it is stuck in the ON state, the short-circuit switch 14 is turned ON to blow the fuse 11. As a result, the corresponding equalization circuit 5 or 6 can be cut off from the cell C or the block B, and the cell C or the block B can be reliably prevented from being in an over-discharged state.

（第２実施形態）
以下、第１実施形態と同一部分には同一符号を付して説明を省略し、異なる部分について説明する。図５に示すように、第２実施形態の電池監視装置２１では、２つの均等化スイッチ１３を直列に接続しており、各均等化スイッチ１３の両端の電圧を検出する。これにより、各均等化スイッチ１３の故障個所を個別に特定する。 (Second Embodiment)
Hereinafter, the same parts as those in the first embodiment are designated by the same reference numerals, the description thereof will be omitted, and different parts will be described. As shown in FIG. 5, in the battery monitoring device 21 of the second embodiment, two equalization switches 13 are connected in series, and the voltage across each equalization switch 13 is detected. As a result, the faulty part of each equalization switch 13 is individually specified.

均等化スイッチ１３（１）のドレイン，ソースをそれぞれ端子Ｖｏｕｔ１，Ｖｏｕｔ２とし、均等化スイッチ１３（２）のソースを端子Ｖｏｕｔ３とする。そして、各端子Ｖｏｕｔ１〜Ｖｏｕｔ３と故障検出回路２２の各入力端子との間に、それぞれスイッチ１５（１）〜１５（３）を配置する。制御回路２３により各スイッチ１５（１）〜１５（３）のＯＮ／ＯＦＦを制御することで、各端子Ｖｏｕｔ１〜Ｖｏｕｔ３と故障検出回路２２の入力端子との接続を切り替えて、均等化スイッチ１３（１），１３（２）の故障を個別に判定する。 The drain and source of the equalization switch 13 (1) are the terminals Vout1 and Vout2, respectively, and the source of the equalization switch 13 (2) is the terminal Vout3. Then, switches 15 (1) to 15 (3) are arranged between the terminals Vout1 to Vout3 and the input terminals of the failure detection circuit 22, respectively. By controlling the ON / OFF of each switch 15 (1) to 15 (3) by the control circuit 23, the connection between each terminal Vout1 to Vout3 and the input terminal of the failure detection circuit 22 is switched, and the equalization switch 13 ( The failures of 1) and 13 (2) are individually determined.

例えば、均等化スイッチ１３（１）の故障を判定する際には、制御回路２３がスイッチ１５（１）及び１５（２）をＯＮにし、スイッチ１５（３）をＯＦＦにする。そして、第１実施形態と同様に、故障検出回路２２が端子Ｖｏｕｔ１−Ｖｏｕｔ２間の電圧をＡ／Ｄ変換して閾値と比較し、故障判定する。均等化スイッチ１３（２）の場合は、制御回路２３がスイッチ１５（１）をＯＦＦにし、スイッチ１５（２）及び１５（２）をＯＮにして故障判定すれば良い。 For example, when determining a failure of the equalization switch 13 (1), the control circuit 23 turns on the switches 15 (1) and 15 (2) and turns off the switch 15 (3). Then, as in the first embodiment, the failure detection circuit 22 A / D converts the voltage between the terminals Vout1 and Vout2 and compares it with the threshold value to determine the failure. In the case of the equalization switch 13 (2), the control circuit 23 may turn off the switch 15 (1) and turn on the switches 15 (2) and 15 (2) to determine the failure.

以上のように第２実施形態によれば、均等化スイッチ１３（１）又は１３（２）の一方がＯＮ固着状態で故障した際にも、他方のスイッチ１３により放電電流を遮断できるので、冗長性を更に向上させることができる。 As described above, according to the second embodiment, even if one of the equalization switches 13 (1) or 13 (2) fails in the ON fixed state, the discharge current can be cut off by the other switch 13, which is redundant. The sex can be further improved.

（第３実施形態）
図６に示す第３実施形態の電子監視装置３１では、フォトカプラ３２を用いて電流を検出することで故障判定を行う。フォトカプラ３２は、発光ダイオード３３とフォトトランジスタ３４とで構成されている。発光ダイオード３３は、ブロック均等化回路６内の均等化スイッチ１３と単位電池セルＣｎの負極側との間に接続されており、フォトトランジスタ３４は、ブロック均等化回路６と電気的に絶縁された二次回路３５内において、電源とグランドとの間にシャント抵抗３６と共に直列に接続され、発光ダイオード３３の光信号を受信可能な位置に配置されている。故障検出回路７は、シャント抵抗３６の端子電圧を検出する。 (Third Embodiment)
In the electronic monitoring device 31 of the third embodiment shown in FIG. 6, a failure is determined by detecting a current using a photocoupler 32. The photocoupler 32 is composed of a light emitting diode 33 and a phototransistor 34. The light emitting diode 33 is connected between the equalization switch 13 in the block equalization circuit 6 and the negative side of the unit battery cell Cn, and the phototransistor 34 is electrically isolated from the block equalization circuit 6. In the secondary circuit 35, it is connected in series with the shunt resistor 36 between the power supply and the ground, and is arranged at a position where the optical signal of the light emitting diode 33 can be received. The failure detection circuit 7 detects the terminal voltage of the shunt resistor 36.

次に、第３実施形態の作用について説明する。均等化スイッチ１３が正常であれば、制御回路８が均等化スイッチ１３をＯＮにすると、ブロック均等化回路６内に均等化電流が流れ、発光ダイオード３３から光が放射される。これによってフォトトランジスタ３４がＯＮとなり、シャント抵抗３６が通電されて端子間に閾値よりも大きい電位差が発生し、故障検出回路７によりＨｉと識別される。 Next, the operation of the third embodiment will be described. If the equalization switch 13 is normal, when the control circuit 8 turns on the equalization switch 13, an equalization current flows in the block equalization circuit 6, and light is radiated from the light emitting diode 33. As a result, the phototransistor 34 is turned on, the shunt resistor 36 is energized, a potential difference larger than the threshold value is generated between the terminals, and the fault detection circuit 7 identifies it as Hi.

一方、均等化スイッチ１３がＯＦＦ固着状態で故障していると、ブロック均等化回路６内に均等化電流が流れないので、発光ダイオード３３が発光せず二次回路３５に電流が流れない。そのため、シャント抵抗３６の端子間に電位差が発生せず、故障検出回路７によりＬｏと識別されるので、均等化スイッチ１３がＯＦＦ固着で故障していると特定できる。 On the other hand, if the equalization switch 13 fails in the OFF fixed state, the equalization current does not flow in the block equalization circuit 6, so that the light emitting diode 33 does not emit light and the current does not flow in the secondary circuit 35. Therefore, no potential difference is generated between the terminals of the shunt resistor 36, and the fault detection circuit 7 identifies Lo, so that it can be identified that the equalization switch 13 is faulty due to sticking to OFF.

また、均等化スイッチ１３が正常であれば、制御回路８が均等化スイッチ１３をＯＦＦにしているとブロック均等化回路６内に電流が流れず、発光ダイオード３３は発光しないので二次回路３５に電流が流れない。一方、均等化スイッチ１３がＯＮ固着状態で故障していると、均等化スイッチ１３をＯＦＦにしていても発光ダイオード３３が発光し、フォトトランジスタ３４がＯＮとなりシャント抵抗３６の端子間に電位差が発生する。したがって、故障検出回路７によりＨｉと識別されて、均等化スイッチ１３がＯＮ固着で故障していると特定できる。 Further, if the equalization switch 13 is normal, if the control circuit 8 turns off the equalization switch 13, no current flows in the block equalization circuit 6, and the light emitting diode 33 does not emit light, so that the secondary circuit 35 is used. No current flows. On the other hand, if the equalization switch 13 fails in the ON fixed state, the light emitting diode 33 emits light even when the equalization switch 13 is turned off, the phototransistor 34 is turned on, and a potential difference is generated between the terminals of the shunt resistor 36. do. Therefore, it can be identified as Hi by the failure detection circuit 7, and it can be identified that the equalization switch 13 has failed due to ON sticking.

（第４実施形態）
図７に示す第４実施形態の電子監視装置４１では、均等化スイッチ１３に対して並列に補助均等化スイッチ４２を接続している。これにより、均等化スイッチ１３がＯＦＦ固着で故障した際に、それに替えて均等化スイッチ４２を用いることができる。具体的には、故障検出回路７が均等化スイッチ１３のＯＦＦ固着故障を検出すると、制御回路８を介してマイコン４へとその故障情報が伝達される。そして、マイコン４が均等化スイッチ４２を用いてブロック均等化を行うよう制御回路８に命令を出力すると、制御回路８が均等化スイッチ４２をＯＮ／ＯＦＦ制御して均等化を行う。 (Fourth Embodiment)
In the electronic monitoring device 41 of the fourth embodiment shown in FIG. 7, the auxiliary equalization switch 42 is connected in parallel to the equalization switch 13. As a result, when the equalization switch 13 fails due to sticking to OFF, the equalization switch 42 can be used instead. Specifically, when the failure detection circuit 7 detects an OFF sticking failure of the equalization switch 13, the failure information is transmitted to the microcomputer 4 via the control circuit 8. Then, when the microcomputer 4 outputs a command to the control circuit 8 to perform block equalization using the equalization switch 42, the control circuit 8 controls the equalization switch 42 ON / OFF to perform equalization.

以上のように構成される第４実施形態によれば、均等化スイッチ１３がＯＦＦ固着で故障しても、補助均等化スイッチ４２により均等化を行うことができるので、冗長性を更に向上させることができる。 According to the fourth embodiment configured as described above, even if the equalization switch 13 fails due to OFF sticking, the auxiliary equalization switch 42 can perform equalization, so that the redundancy is further improved. Can be done.

（その他の実施形態）
均等化スイッチは、ＦＥＴに限ることなくバイポーラトランジスタにより構成しても良い。
電池ブロックの数と電池セルの数は、同じである必要はない。
第２実施形態において、均等化スイッチを３個以上直列に接続しても良い。
ヒューズ１１及び短絡スイッチ１３は、必要に応じて設ければ良い。
本開示は、実施例に準拠して記述されたが、本開示は当該実施例や構造に限定されるものではないと理解される。本開示は、様々な変形例や均等範囲内の変形をも包含する。加えて、様々な組み合わせや形態、さらには、それらに一要素のみ、それ以上、あるいはそれ以下、を含む他の組み合わせや形態をも、本開示の範疇や思想範囲に入るものである。 (Other embodiments)
The equalization switch is not limited to the FET and may be configured by a bipolar transistor.
The number of battery blocks and the number of battery cells do not have to be the same.
In the second embodiment, three or more equalization switches may be connected in series.
The fuse 11 and the short-circuit switch 13 may be provided as needed.
The present disclosure has been described in accordance with the examples, but it is understood that the present disclosure is not limited to the examples and structures. The present disclosure also includes various variations and variations within a uniform range. In addition, various combinations and forms, as well as other combinations and forms that include only one element, more, or less, are within the scope and scope of the present disclosure.

図面中、１は電池ユニット、２は電池監視装置、３は電池監視ユニット、４はマイクロコンピュータ、５はセル均等化回路、６はブロック均等化回路、７は故障検出回路、８は制御回路、１１はヒューズ、１２は電流制限抵抗、１３は均等化スイッチ、１４は短絡スイッチを示す。 In the drawing, 1 is a battery unit, 2 is a battery monitoring device, 3 is a battery monitoring unit, 4 is a microcomputer, 5 is a cell equalization circuit, 6 is a block equalization circuit, 7 is a failure detection circuit, and 8 is a control circuit. 11 is a fuse, 12 is a current limiting resistor, 13 is an equalization switch, and 14 is a short-circuit switch.

Claims (7)

複数の電池ブロック（Ｂ）を直列に接続して構成される電池ユニット（１）の電圧を監視するもので、
各電池ブロック内の電池セル（Ｃ）間の電圧を均等化する均等化スイッチ（１３）を有するセル均等化回路（５）と、
各電池ブロック間の電圧を均等化する均等化スイッチ（１３）を有するブロック均等化回路（６）と、
前記均等化スイッチのＯＮ／ＯＦＦ状態に応じて当該スイッチに印加される電圧値又は当該スイッチに流れる電流値を所定の値と比較して、当該スイッチの故障判定を行う故障検出回路（７，２２）と、
前記均等化スイッチのＯＮ／ＯＦＦを制御して各電池セル間及び各電池ブロック間の均等化制御を行うと共に、
前記セル均等化回路又は前記ブロック均等化回路の一方について均等化スイッチの故障が判定されると、その故障の状態に応じて均等化を行う際に流れる均等化電流の経路を切り替えて均等化を継続して行うように制御する制御回路（８）とを備える電池監視装置。 It monitors the voltage of the battery unit (1) configured by connecting a plurality of battery blocks (B) in series.
A cell equalization circuit (5) having an equalization switch (13) for equalizing the voltage between the battery cells (C) in each battery block, and a cell equalization circuit (5).
A block equalization circuit (6) having an equalization switch (13) for equalizing the voltage between each battery block,
A failure detection circuit (7, 22) that determines a failure of the switch by comparing the voltage value applied to the switch or the current value flowing through the switch according to the ON / OFF state of the equalization switch with a predetermined value. )When,
The ON / OFF of the equalization switch is controlled to perform equalization control between each battery cell and each battery block, and at the same time.
When a failure of the equalization switch is determined for either the cell equalization circuit or the block equalization circuit, the equalization current path that flows when performing equalization is switched according to the state of the failure to perform equalization. A battery monitoring device including a control circuit (8) that controls continuous operation. 前記制御回路は、前記ブロック均等化回路の均等化スイッチが故障と判定されると、前記セル均等化回路により均等化を行うように切り替える請求項１記載の電池監視装置。 The battery monitoring device according to claim 1, wherein the control circuit is switched so as to perform equalization by the cell equalization circuit when the equalization switch of the block equalization circuit is determined to be faulty. 前記制御回路は、前記セル均等化回路の均等化スイッチが故障と判定されると、故障が発生したセル均等化回路に替えて、当該セル均等化回路が属する電池ブロックのブロック均等化回路により均等化を行うように切り替える請求項１又は２記載の電池監視装置。 When the equalization switch of the cell equalization circuit is determined to be defective, the control circuit is equalized by the block equalization circuit of the battery block to which the cell equalization circuit belongs, instead of the cell equalization circuit in which the failure has occurred. The battery monitoring device according to claim 1 or 2, which is switched so as to perform the conversion. 前記均等化スイッチが、複数直列に接続されている請求項１から３の何れか一項に記載の電池監視装置。 The battery monitoring device according to any one of claims 1 to 3, wherein a plurality of equalization switches are connected in series. 前記制御回路は、前記複数の均等化スイッチのそれぞれに印加される電圧を個別に検出し、それぞれの均等化スイッチについて故障判定を行う請求項４記載の電池監視装置。 The battery monitoring device according to claim 4, wherein the control circuit individually detects a voltage applied to each of the plurality of equalization switches and determines a failure of each equalization switch. 前記均等化スイッチに並列に接続される補助均等化スイッチ（４２）を備え、
前記制御回路は、前記均等化スイッチの故障がＯＦＦ状態での固着によるものであれば、前記補助均等化スイッチのＯＮ／ＯＦＦを制御して均等化を行う請求項１から５の何れか一項に記載の電池監視装置。 An auxiliary equalization switch (42) connected in parallel to the equalization switch is provided.
The control circuit is any one of claims 1 to 5, wherein if the failure of the equalization switch is due to sticking in the OFF state, the control circuit controls ON / OFF of the auxiliary equalization switch to perform equalization. The battery monitoring device described in. 前記セル均等化回路と前記ブロック均等化回路は、それぞれ電流量を制限する電流制限抵抗（１２）と、この電流制限抵抗に並列に接続される短絡スイッチ（１３）と、これらの並列回路に直列に接続されるヒューズ（１１）とを有し、
前記制御回路は、前記均等化スイッチの故障がＯＮ状態での固着によるものであれば、前記短絡スイッチをＯＮして前記ヒューズを溶断させる請求項１から６の何れか一項に記載の電池監視装置。 The cell equalization circuit and the block equalization circuit have a current limiting resistor (12) that limits the amount of current, a short circuit switch (13) connected in parallel to the current limiting resistor, and a series of these parallel circuits. With a fuse (11) connected to
The battery monitoring according to any one of claims 1 to 6, wherein the control circuit turns on the short-circuit switch to blow the fuse if the failure of the equalization switch is due to sticking in the ON state. Device.
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