JP2011247760A - Abnormality detection circuit and power supply unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the risk that, in the case of disconnection of wiring, a secondary battery is erroneously determined to be normal.SOLUTION: An abnormality detection circuit includes a voltage abnormality determination part 122, notification signal generation parts 121, a control part 101 for determining whether a battery block 106 is abnormal or not, and an OR circuit 103 for outputting a composite notification signal 111 resulting from operating OR among notification signals from respective notification signal generation parts 121. Each notification signal generation part 121 generates a notification signal 105 including pulses having a first pulse width with a set period when the battery block is not abnormal, but sets a pulse width of the notification signal 105 to a second pulse width different from the first pulse width to generate the notification signal 105 when the battery block is abnormal. The control part 101 determines the battery block 106 to be not abnormal when a pulse width of pulses included in the composite notification signal 111 is the first pulse width, but determines the battery block 106 to be abnormal when pulses having a pulse width different from the first pulse width are included in the notification signal 105.

Description

  The present invention relates to an abnormality detection circuit that detects an abnormality of a secondary battery, and a power supply device including the abnormality detection circuit.

  Electric vehicles and hybrid vehicles are attracting attention as next-generation eco-cars. And the technical development of the secondary battery used as a power supply of such an eco-car is progressing. Improvements in the performance of secondary batteries, which are thought to influence the performance of automobiles, are being pursued every day.

  Moreover, the reliability level requested | required of a secondary battery is also increasing with the improvement of the performance of a secondary battery. Therefore, a power supply device is known that detects a voltage of a cell and transmits a signal indicating the occurrence of the abnormality to a control device when the voltage becomes an abnormal value (see, for example, Patent Document 1).

JP 2003-297407 A

  By the way, in the technique described in Patent Document 1, when no abnormality occurs, a signal indicating the occurrence of abnormality is not transmitted. For this reason, if the wiring between the output circuit that transmits a signal indicating the occurrence of an abnormality and the control device is disconnected, the signal indicating the occurrence of the abnormality is not transmitted to the control device even if an abnormality occurs. Therefore, the control device cannot be distinguished from the normal time. As a result, the control device has a disadvantage that the cell is determined to be normal when the wiring between the cell voltage determination unit and the control device is disconnected.

  The object of the present invention is to erroneously determine that the secondary battery is normal even when the wiring between the output circuit that outputs a signal indicating the occurrence of abnormality of the secondary battery and the control unit is disconnected. It is an object to provide an abnormality detection circuit and a power supply device that can reduce the risk of occurrence.

  The abnormality detection circuit according to the present invention is provided corresponding to each of the plurality of abnormality detection units, a plurality of abnormality detection units that detect abnormality corresponding to each of the plurality of secondary batteries, and the plurality of abnormality detection units A plurality of notification signal generators each for generating and outputting a notification signal indicating the presence or absence of detection of the abnormality, and a logical sum operation for outputting a signal obtained by logically summing the notification signals from the plurality of notification signal generators And a control unit for determining the presence or absence of abnormality of the secondary battery based on the ORed signal output from the OR operation unit, and each notification signal generation unit includes the corresponding abnormality When the detection unit has not detected an abnormality, a signal including a pulse having a preset first pulse width is generated as the notification signal at a preset period in synchronization with each other, and the corresponding signal is generated. When the normal detection unit detects an abnormality, the pulse width of the pulse in the notification signal is set to a second pulse width different from the first pulse width to generate the notification signal. When the pulse width of the pulse included in the logical sum signal is the first pulse width, it is determined that there is no abnormality in the plurality of secondary batteries, and the logical sum signal includes the first pulse width. When a pulse having a pulse width different from the pulse width is included, it is determined that an abnormality has occurred in at least one of the secondary batteries.

  According to this configuration, when the abnormality detection unit has not detected an abnormality, the notification signal generation unit uses a signal including a pulse having a preset first pulse width as the notification signal at a preset setting cycle. Generate and output. The notification signal generation unit generates and outputs the notification signal by setting the pulse width in the notification signal to a second pulse width different from the first pulse width when the abnormality detection unit detects an abnormality. Therefore, a pulse is output as a notification signal regardless of whether there is an abnormality in the secondary battery. And since the signal indicating the presence or absence of abnormality in each secondary battery is combined into one notification signal and output to the control unit, the number of notification signal generation units is the same between the OR operation unit and the control unit. There is no need for wiring. Thereby, wiring saving can be achieved.

  Then, if the pulse width of the pulse included in the notification signal is the first pulse width, the control unit determines that there is no abnormality in the secondary battery. When the notification signal includes a pulse having a pulse width different from the first pulse width, the control unit determines that an abnormality has occurred in the secondary battery. Thereby, abnormality of a secondary battery can be specified.

  Furthermore, when logically summing a plurality of notification signals, if the timing of the pulses included in each notification signal is not synchronized, if the signals are simply logically summed and the signals are combined, the combined pulse width is Both the one pulse width and the second pulse width are different, and the presence or absence of abnormality is not correctly indicated. However, according to this configuration, each notification signal generation unit outputs a pulse at a timing synchronized with each other, so that the notification signal after combining signals that correctly indicate the presence / absence of an abnormality can be simply ORed. Can be generated. As a result, a plurality of notification signals can be synthesized using an OR operation unit that simply ORs the plurality of notification signals, so that a plurality of notification signals can be synthesized with a simple configuration. .

  Further, the abnormality detection circuit according to the present invention is provided corresponding to each of the plurality of abnormality detection units and a plurality of abnormality detection units that detect abnormality corresponding to each of the plurality of secondary batteries, and the plurality of abnormality detection units. A plurality of notification signal generation units that respectively generate and output notification signals indicating whether or not the abnormality is detected by the detection unit, and a logic that outputs a logical sum of the notification signals from the plurality of notification signal generation units A sum calculating unit, and a control unit for determining the presence or absence of abnormality of the secondary battery based on the logical sum signal output from the logical sum calculating unit, wherein each of the notification signal generating units is mutually A signal including a preset reference pulse is generated as the notification signal at a preset setting period at a synchronized timing, and when the corresponding abnormality detection unit detects an abnormality, in addition to the reference pulse, An abnormal pulse indicating normal is included in the notification signal at a timing different from that of the reference pulse, and the control unit includes the reference pulse in the ORed signal and does not include the abnormal pulse. It is determined that there is no abnormality in the secondary battery, and it is determined that an abnormality has occurred in any of the secondary batteries when the logical sum signal includes the reference pulse and the abnormal pulse. To do.

  According to this configuration, the notification signal generation unit generates and outputs a signal including a preset reference pulse as a notification signal at a preset setting period when the abnormality detection unit does not detect an abnormality. To do. Further, when the abnormality detection unit detects an abnormality, the notification signal generation unit generates and outputs the notification signal by adding an abnormal pulse in addition to the reference pulse in the notification signal, so that there is an abnormality in the secondary battery. A pulse is output as a notification signal. And since the signal indicating the presence or absence of abnormality in each secondary battery is combined into one notification signal and output to the control unit, the number of notification signal generation units is the same between the OR operation unit and the control unit. There is no need for wiring. Thereby, wiring saving can be achieved.

  And in logical OR of a plurality of notification signals, if the timing of the reference pulse included in each notification signal is not synchronized, if the signal is simply ORed and synthesized, The reference pulse output from each notification signal generation unit is included at different timings, and the reference pulse and the abnormal pulse cannot be discriminated. However, according to this configuration, each notification signal generator outputs the reference pulse at a timing synchronized with each other, so that the notification signal can be discriminated from the reference pulse and the abnormal pulse simply by performing a logical OR. Can be synthesized. As a result, a plurality of notification signals can be synthesized using an OR operation unit that simply ORs the plurality of notification signals, so that a plurality of notification signals can be synthesized with a simple configuration. .

  Each of the notification signal generation units includes the abnormal pulse in the notification signal at a different timing set in advance corresponding to each of the notification signal generation units, and the control unit performs the OR operation. When the abnormal pulse is included in the signal, an abnormality has occurred in the secondary battery corresponding to the abnormality detecting unit corresponding to the communication signal generating unit in which the timing at which the abnormal pulse was included is set. Is preferably determined.

  According to this configuration, the timing of the abnormal pulse output by each notification signal generator is set in advance at a different timing. Then, when the abnormal signal is included in the logical sum signal, the control unit has a secondary battery corresponding to the abnormality detection unit corresponding to the communication signal generation unit in which the timing at which the abnormal pulse is included is set. It is determined that an abnormality has occurred. Thereby, it is possible to identify a secondary battery in which an abnormality has occurred among a plurality of secondary batteries.

  Each of the notification signal generation units includes the abnormal pulse in the notification signal at a different timing, and the control unit includes the reference signal when the abnormal pulse is included in the ORed signal. It is preferable to count the number of abnormal pulses included between the pulse and the next reference pulse as the number of secondary batteries in which an abnormality has occurred.

  According to this configuration, since each notification signal generation unit includes an abnormal pulse in the notification signal at different timings, the abnormal pulse does not overlap in the logical sum signal. Therefore, when the abnormal signal is included in the logical sum signal, the control unit determines the number of abnormal pulses included between the reference pulse and the next reference pulse of the secondary battery in which the abnormality has occurred. It can be counted as a number.

  Moreover, it is preferable that the said control part determines with some abnormality having arisen, when a pulse is not contained in the said notification signal.

  According to this configuration, for example, when the notification signal does not include a pulse due to a disconnection in the signal path from the notification signal generation unit to the control unit or a failure of the notification signal generation unit, the control unit Therefore, it is determined that some abnormality has occurred. Therefore, even if the wiring between the output circuit that outputs a signal indicating the occurrence of abnormality of the secondary battery and the control unit is disconnected, the secondary battery is not erroneously determined to be normal, It can be determined that some abnormality has occurred.

  The control unit may include at least one of the notification signal generation unit and a signal path from the notification signal generation unit to the control unit when the notification signal does not include a pulse for a period exceeding the set period. It is preferable to determine that an abnormality has occurred in part.

  According to this configuration, since the notification signal generation unit outputs a pulse at a set cycle as a notification signal regardless of whether the secondary battery is abnormal, the notification signal generation unit and the notification signal generation unit to the control unit If the signal path leading to is normal, it is considered that the state in which the notification signal does not include a pulse continues for a period exceeding the set period. Therefore, when the notification signal does not include a pulse for a period exceeding the set cycle, the control unit detects an abnormality in at least a part of the notification signal generation unit and the signal path from the notification signal generation unit to the control unit. Is determined to have occurred. Thereby, it becomes possible to detect disconnection of the signal path.

  The reference signal generator may further include a reference signal generator configured to generate a reference signal that repeats the pulse having the first pulse width at the set period, and the plurality of notification signal generators may include the reference signal generated by the reference signal generator. It is preferable that the pulses in the notification signal output from each other are synchronized with each other by generating the notification signal on the basis of the notification signal.

  According to this configuration, since all the notification signals output from the plurality of notification signal generation units are generated based on the same reference signal, it is easy to synchronize the timing of each notification signal.

  A reference signal generating unit configured to generate a reference signal that repeats the reference pulse at the set period; and the plurality of notification signal generating units are configured to generate the notification signal based on the reference signal generated by the reference signal generating unit. It is preferable that the reference pulses in the notification signals output from each other are synchronized with each other.

  According to this configuration, all the notification signals output from the plurality of notification signal generation units are generated based on the same reference signal, so that it is easy to synchronize the timing of the reference pulse in each notification signal. .

  Moreover, the power supply device according to the present invention includes the above-described abnormality detection circuit and the secondary battery.

  According to this configuration, in the power supply device using the secondary battery, an abnormality of the secondary battery can be detected, and the wiring between the output circuit that outputs a signal indicating the occurrence of the abnormality of the secondary battery and the control unit is disconnected. Even in this case, it is possible to reduce the possibility that the secondary battery is erroneously determined to be normal.

  The abnormality detection circuit and the power supply device having such a configuration are configured so that the secondary battery is erroneously detected even when the wiring between the output circuit that outputs a signal indicating the occurrence of the abnormality of the secondary battery and the control unit is disconnected. It is possible to reduce the risk of determining that is normal.

It is a block diagram which shows an example of a structure of the power supply device provided with the abnormality detection circuit which concerns on one Embodiment of this invention. It is a block diagram which shows an example of a structure of the voltage monitoring part shown in FIG. It is the figure which showed the output signal with respect to the input signal of the voltage monitoring part shown in FIG. It is a circuit diagram which shows an example of a structure of the notification signal production | generation part shown in FIG. It is a signal waveform diagram for demonstrating operation | movement of the notification signal production | generation part shown in FIG. It is a circuit diagram which shows an example of a structure of the control part shown in FIG. FIG. 7 is a signal waveform diagram for explaining the operation of the counter shown in FIG. 6. 3 is a flowchart illustrating an example of an operation of the power supply device illustrated in FIG. 1. It is a signal waveform diagram showing an example of signal waveforms of a reference signal, a notification signal, and a combined notification signal when all the battery blocks are normal. It is a signal waveform diagram showing an example of signal waveforms of a reference signal, a notification signal, and a combined notification signal when an abnormality occurs in one of the battery blocks. It is a signal waveform diagram showing an example of signal waveforms of a reference signal, a notification signal, and a combined notification signal when abnormality occurs in all of the battery blocks.

  Embodiments according to the present invention will be described below with reference to the drawings. In addition, the structure which attached | subjected the same code | symbol in each figure shows that it is the same structure, The description is abbreviate | omitted. FIG. 1 is a block diagram illustrating an example of a configuration of a power supply device 113 including an abnormality detection circuit 1 according to an embodiment of the present invention.

  A power supply device 113 shown in FIG. 1 includes an abnormality detection circuit 1 and battery blocks 106-1, 106-2, 106-3 (secondary batteries). The abnormality detection circuit 1 includes a control unit 101, voltage monitoring units 102-1, 102-2, and 102-3 (abnormality detection unit), an OR circuit 103 (logical sum operation unit), and input insulating elements 107-1 and 107-2. 107-3, output insulating elements 108-1, 108-2, 108-3, and an oscillator OSC.

  Battery blocks 106-1, 106-2, 106-3, voltage monitoring units 102-1, 102-2, 102-3, input insulating elements 107-1, 107-2, 107-3, and output insulating element 108- Subscripts (numbers with hyphens) in reference numerals 1, 108-2, and 108-3 are configured such that the same subscripts are assigned to the corresponding components. For example, a voltage monitoring unit 102-1, an input insulating element 107-1, and an output insulating element 108-1 are provided corresponding to the battery block 106-1. Further, reference signals 104 and notification signals 105 and 109 described later are also described with the same subscripts as the corresponding battery blocks.

  Hereinafter, the battery blocks 106-1, 106-2, 106-3 are collectively referred to as the battery block 106, and the voltage monitoring units 102-1, 102-2, 102-3 are collectively referred to as the voltage monitoring unit 102. When the input insulating elements 107-1, 107-2, and 107-3 are collectively referred to as the input insulating element 107, the output insulating elements 108-1, 108-2, and 108-3 are collectively referred to as the output insulating element. 108, the reference signals 104-1, 104-2, 104-3 are collectively referred to as the reference signal 104, and the notification signals 105-1, 105-2, 105-3 are collectively referred to as the notification signal 105. The notification signals 109-1, 109-2, and 109-3 are collectively referred to as the notification signal 109. In addition, when individual components and signals are indicated, the reference numerals are appended.

  The battery block 106 is configured by connecting a plurality of unit cells 112 in series, parallel, or a combination of series and parallel. The unit cell 112 is a secondary battery cell such as a secondary battery, for example, a lithium ion secondary battery or a nickel hydride secondary battery.

  In addition, although the battery block 106 was shown as an example of the secondary battery which concerns on a claim, the secondary battery which concerns on a claim may be a single cell. Further, the number of battery blocks 106 (the number of secondary batteries) is not limited to three, and may be one, two, or four or more.

  The input insulating element 107 and the output insulating element 108 are insulating elements configured using, for example, a photocoupler. The input insulating element 107 is interposed between the control unit 101 and the voltage monitoring unit 102 to insulate between the control unit 101 and the voltage monitoring unit 102. The output insulating element 108 is interposed between the voltage monitoring unit 102 and the OR circuit 103 to insulate the voltage monitoring unit 102 from the OR circuit 103.

  Voltage monitoring units 102-1, 102-2, and 102-3 detect the terminal voltages of battery blocks 106-1, 106-2, and 106-3, respectively. Since the battery blocks 106-1, 106-2, and 106-3 are connected in series, the reference potentials of the voltage monitoring units 102-1, 102-2, and 102-3 are different from each other. Therefore, when the control unit 101 or the OR circuit 103 is directly connected to the voltage monitoring units 102-1, 102-2, 102-3, the potential difference between the voltage monitoring units 102-1, 102-2, 102-3. Will not work properly.

  Therefore, the voltage monitoring units 102-1, 102-2, and 102-3 are insulated by isolating the voltage monitoring unit 102 from the control unit 101 and the OR circuit 103 by the input insulating element 107 and the output insulating element 108. The potential difference between them is prevented from affecting the circuit operation.

  The control unit 101 includes, for example, a CPU (Central Processing Unit) that performs predetermined arithmetic processing, a ROM (Read Only Memory) that stores a predetermined control program, and a RAM (Random Access Memory) that temporarily stores data. The reference signal generation unit 101a and the peripheral circuits thereof are configured. The control unit 101 is not limited to an example using a CPU, and may be configured by combining logic circuits, for example.

  For example, the oscillator OSC generates a clock signal CLK having a pulse width t and a period 2t, and supplies the clock signal CLK to the control unit 101 and the voltage monitoring unit 102.

  The reference signal generation unit 101a generates a periodic signal that repeats a pulse having a pulse width t (first pulse width) at a period T (set period) as the reference signal 110. Then, the reference signal generation unit 101a outputs the reference signal 110 to the voltage monitoring unit 102 via the input insulating element 107.

  The reference signal generation unit 101a uses the clock signal CLK to output, for example, a pulse of the clock signal CLK as the reference signal 110 with a frequency of once every N times, thereby having a pulse width t and a period T = 2t × N. A reference signal 110 can be output. The reference signal generator 101a may be configured using a so-called clock generator.

  If the pulse width of the combined notification signal 111 output from the OR circuit 103, that is, the ORed signal, is the pulse width t, the control unit 101 determines that the battery blocks 106-1, 106-2, 106-3 are used. Is determined to be normal. In addition, when the pulse width of the composite notification signal 111 is different from the pulse width t, for example, 2t, the control unit 101 generates an abnormality in at least one of the battery blocks 106-1, 106-2, and 106-3. It is determined that

  The control unit 101 also includes at least part of the signal path from the OR circuit 103 to the control unit 101 and the OR circuit 103 when the composite notification signal 111 does not include a pulse for a period exceeding the period T. It is determined that an abnormality has occurred.

  The input insulating elements 107-1, 107-2, and 107-3 receive the reference signal 110 from the reference signal generation unit 101a, and correspond to the isolated reference signals 104-1, 104-2, and 104-3, respectively. The voltage is output to the voltage monitoring units 102-1, 102-2, and 102-3.

  The voltage monitoring unit 102 monitors terminal voltages (terminal voltages) at both ends of each battery block 106. FIG. 2 is a block diagram illustrating an example of the configuration of the voltage monitoring unit 102-1 illustrated in FIG. The voltage monitoring unit 102-1 illustrated in FIG. 2 includes, for example, a notification signal generation unit 121 and a voltage abnormality determination unit 122 (abnormality detection unit). The voltage monitoring units 102-2 and 102-3 are configured in the same manner as the voltage monitoring unit 102-1, and thus the description thereof is omitted.

  The voltage abnormality determination unit 122 in the voltage monitoring unit 102-1 is connected to both ends of the corresponding battery block 106-1, and detects the terminal voltage. The voltage abnormality determination unit 122 is configured using, for example, a comparator. Then, for example, when the detected terminal voltage exceeds the upper limit voltage value indicating the overvoltage of the battery block 106-1 or falls below the lower limit voltage value indicating the overdischarge, the voltage abnormality determination unit 122 detects an abnormality. The detection signal Err shown is set to a high level, for example, and output to the notification signal generator 121.

  As an example of the abnormality detection unit, the voltage abnormality determination unit 122 that detects the abnormality of the voltage of the battery block 106 is shown. The abnormality of the battery block 106 may be detected by detecting the abnormality.

  When the voltage abnormality determination unit 122 has not detected an abnormality, for example, when the detection signal Err is at a low level, the notification signal generation unit 121 uses the reference signal 104-1 as the notification signal 105-1 as it is as the output insulating element 108-1. Output to. In addition, when the voltage abnormality determination unit 122 detects an abnormality, for example, when the detection signal Err is at a high level, the notification signal generation unit 121 extends the pulse width of the reference signal 104-1 to change the pulse width, for example. The notification signal 105-1 is output to the output insulating element 108-1.

  FIG. 3 is a diagram showing an output signal for the input signal of the voltage monitoring unit 102-1 shown in FIG. The same applies to the voltage monitoring unit 102-2 and the voltage monitoring unit 102-3. Here, the reference signal 104-1 is a pulse signal having a pulse width t and a period T. The voltage monitoring unit 102-1 outputs different signals depending on whether the voltage of the battery block 106-1 is normal or abnormal.

  When the voltage of the battery block 106-1 is normal, the voltage monitoring unit 102-1 outputs a pulse signal having the same pulse width t and period T as that of the reference signal 104-1 as the notification signal 105-1, for overdischarge / overvoltage, etc. When an abnormality occurs, a pulse signal having a pulse width 2t and a period T different from that of the reference signal 104-1 is output as the notification signal 105-1.

  FIG. 4 is a circuit diagram showing an example of the configuration of the notification signal generator 121 shown in FIG. The notification signal generation unit 121 illustrated in FIG. 4 includes a multiplexer MUX, a flip-flop FF1, and a logic gate A1.

  The reference signal 104 is input to the set terminal of the flip-flop FF1. The logic gate A1 ANDs the signal obtained by inverting the reference signal 104 and the clock signal CLK and outputs the result to the reset terminal of the flip-flop FF1.

  The multiplexer MUX selects one of the reference signal 104 and the output signal FFout of the flip-flop FF1 according to the detection signal Err and outputs it as the notification signal 105.

  FIG. 5 is a signal waveform diagram for explaining the operation of the notification signal generator 121 shown in FIG. The reference signal 104 has the same signal waveform as the reference signal 110 because the reference signal 110 output from the reference signal generation unit 101 a is insulated by the input insulating element 107. Since the reference signal 110 is obtained by outputting the pulse of the clock signal CLK once every N times, the pulse of the reference signal 104 is output in synchronization with the clock signal CLK.

  Then, the flip-flop FF1 is set at the rising edge of the reference signal 104 and reset at the rising edge of the next clock signal CLK. As a result, the output signal FFout is a signal having a pulse width of 2t and a period of T, that is, a signal waveform indicating that the voltage abnormality determination unit 122 has detected an abnormality.

  When no abnormality is detected in the battery block 106 and the detection signal Err is at a low level, the reference signal 104 is selected by the multiplexer MUX, and the reference signal 104 is output as it is as the notification signal 105. On the other hand, when the detection signal Err is high level, that is, when abnormality of the battery block 106 is detected, the multiplexer MUX selects and notifies the output signal FFout, that is, a signal indicating that the voltage abnormality determination unit 122 has detected abnormality. Output as signal 105.

  In this way, the notification signals 105-1 (105-2 and 105-3) and the notification signals 105-1 and 105-2 and 105-3 shown in FIG. , 108-3, notification signals 109-1 (109-2, 109-3) obtained by insulation are generated.

  Although an example in which the notification signal 105 having a pulse width 2t that is twice that of the normal time is obtained at the time of abnormality is shown, the pulse width of the notification signal 105 may be different between the time of abnormality and the normal time. The pulse width is not limited. In addition, an example in which the pulse width of the notification signal 105 is longer than that in the normal state at the time of abnormality has been described. However, the pulse width of the notification signal 105 may be shorter than that in the normal state at the time of abnormality.

  In this way, the notification signals 105-1, 105-2, and 105-3 output by the voltage monitoring units 102-1, 102-2, and 102-3, respectively, are output as the output insulating elements 108-1 and 108-2. , 108-3, and output to the OR circuit 103 as notification signals 109-1, 109-2, 109-3.

  The OR circuit 103 ORs the notification signals 109-1, 109-2, and 109-3 and synthesizes them, and transmits them to the control unit 101 as a combined notification signal 111. Based on the synthesis notification signal 111, the control unit 101 recognizes whether there is a voltage abnormality in any of the battery blocks 106-1, 106-2, 106-3, or whether there is a disconnection or a failure in the OR circuit 103.

  FIG. 6 is a circuit diagram showing an example of the configuration of the control unit 101 shown in FIG. In FIG. 6, the description of the reference signal generation unit 101a is omitted. The control unit 101 illustrated in FIG. 6 includes, for example, an exclusive OR gate EOR, a flip-flop FF2, and a counter CT.

  The exclusive OR gate EOR outputs a signal obtained by exclusive ORing the reference signal 110 and the synthesis notification signal 111 to the clock terminal of the flip-flop FF2. When the output signal of the exclusive OR gate EOR rises, the flip-flop FF2 generates a battery abnormality detection signal Eb indicating that an abnormality has occurred in at least one of the battery blocks 106-1, 106-2, 106-3. Latch it high.

  The counter CT counts the rising edge of the clock signal CLK, and when the count value becomes N, sets the count-up signal to high level and outputs it as the error signal Ew. N is N when the reference signal generation unit 101a outputs the pulse of the clock signal CLK as the reference signal 110 at a frequency of once every N times, and when the cycle of the clock signal CLK is 2t, T = 2t × N.

  The counter CT is reset when the synthesis notification signal 111 becomes high level.

  FIG. 7 is a signal waveform diagram for explaining the operation of the counter CT shown in FIG. FIG. 7 shows a case where N = 3. First, if the voltage monitoring unit 102 and the OR circuit 103 operate normally and no disconnection occurs, the OR circuit 103 outputs a pulse signal of the synthesis notification signal 111 with a period T. Then, the counter CT is reset by the pulse of the synthesis notification signal 111, and the pulse of the clock signal CLK synchronized with this pulse is not counted.

  Then, after the synthesis notification signal 111 becomes low level, the pulses of the clock signal CLK are counted by the counter CT. However, when the count value becomes N (3), the pulse signal of the synthesis notification signal 111 becomes high level again, and the counter CT is reset.

  Therefore, if the voltage monitoring unit 102 and the OR circuit 103 operate normally and no disconnection occurs, the counter CT does not count up and the error signal Ew remains at a low level.

  On the other hand, if the OR circuit 103 fails or the signal path from the OR circuit 103 to the control unit 101 is disconnected, the counter CT is not reset by the composite notification signal 111, so the counter CT counts the pulses of the clock signal CLK. Keep doing. Then, the count value becomes N (3), the counter CT is counted up, and the error signal Ew is set to the high level and output. As a result, it is possible to detect the occurrence of an abnormality in which the OR circuit 103 fails or the signal path from the OR circuit 103 to the control unit 101 is disconnected.

  Next, the operation of the power supply device 113 shown in FIG. 1 will be described with reference to FIG. 8, FIG. 9, and FIG. FIG. 8 is a flowchart showing an example of the operation of the power supply device 113 shown in FIG.

  First, the reference signal 110 is output from the reference signal generation unit 101a (step S1). The reference signal 110 is input to the voltage monitoring units 102-1, 102-2, and 102-3 via the input insulating elements 107-1, 107-2, and 107-3 (Step S2). By sandwiching the input insulating elements 107-1, 107-2, 107-3 between the reference signal generation unit 101a and the voltage monitoring unit 102, the voltage monitoring units 102-1, 102-2, 102-3 are respectively connected. The potentials of the input signals can be made equal.

  The voltage monitoring units 102-1, 102-2, and 102-3 perform voltage abnormality determination of the battery blocks 106-1, 106-2, and 106-3 (step S3). When the voltages of the battery blocks 106-1, 106-2, 106-3 are normal (YES in step S3), the voltage monitoring units 102-1, 102-2, 102-3 receive the reference signal 104-. Signals having the same pulse width as 1, 104-2, 104-3 are output as notification signals 105-1, 105-2, 105-3 (step S4).

  On the other hand, when abnormalities such as overdischarge and overvoltage occur (NO in step S3), the voltage monitoring units 102-1, 102-2, and 102-3 are twice as large as the reference signals 104-1, 104-2, and 104-3. Are output as notification signals 105-1, 105-2, and 105-3 (step S5).

  The notification signals 105-1, 105-2, and 105-3 are input to the OR circuit 103 via the output isolation elements 108-1, 108-2, and 108-3, and are ORed and synthesized by the OR circuit 103. (Step S6).

  FIG. 9 shows the reference signal 104 when all the battery blocks 106-1, 106-2, and 106-3 are normal, that is, the reference signal 110, and the notification signals 105-1, 105-2, and 105-3. It is a signal waveform diagram showing an example of signal waveforms of notification signals 109-1, 109-2, 109-3 and a combined notification signal 111. Further, FIG. 10 shows, for example, the reference signal 104 (reference signal 110) and the notification signals 105-1, 105-2, and 105-3, that is, the notification signals 109-1 and 109 when an abnormality occurs in the battery block 106-2. FIG. 10 is a signal waveform diagram showing an example of signal waveforms of −2, 109-3 and a synthesis notification signal 111.

  First, when all the battery blocks 106-1, 106-2, 106-3 are normal, as shown in FIG. 9, the notification signals 109-1, 109-2, 109-3 are all pulse widths. t and a pulse signal having a period T.

  Since the notification signals 109-1, 109-2, and 109-3 are generated based on the reference signal 104, that is, the reference signal 110, the timings of the pulses are synchronized. As a result, the combined notification signal 111 obtained by ORing the notification signals 109-1, 109-2, 109-3 is also a pulse signal having a pulse width t and a period T.

  If the pulses of the notification signals 109-1, 109-2, and 109-3 are not synchronized and the timing of the pulses varies at an arbitrary timing, the pulses of the combined notification signal 111 obtained by ORing them together The width may be longer than the pulse width t. If the pulse width of the composite notification signal 111 is longer than the pulse width t, the control unit 101 may erroneously recognize that a battery abnormality has occurred, that is, the battery abnormality detection signal Eb may be at a high level. is there.

  However, in the abnormality detection circuit 1 shown in FIG. 1, the pulse timings of the notification signals 109-1, 109-2, and 109-3 are generated and synchronized based on the reference signal 104, so that as shown in FIG. When the notification signals 109-1, 109-2, and 109-3 are all pulse signals having a pulse width t and a period T, that is, all of the battery blocks 106-1, 106-2, and 106-3 are normal. In some cases, the composite notification signal 111 is also a pulse signal having a pulse width t and a period T. This prevents the control unit 101 from erroneously recognizing that a battery abnormality has occurred.

  Since the notification signals 109-1, 109-2, 109-3 are synchronized in this way, the OR circuit 103 synthesizes the notification signals 109-1, 109-2, 109-3 and generates By combining the two combined notification signals 111, the number of wires can be reduced as compared with the case where the notification signals 109-1, 109-2, and 109-3 are individually transmitted to the control unit 101.

  In particular, when the power supply device 113 is used as a power source for a vehicle such as an electric vehicle or a hybrid vehicle, the control unit 101 may be configured as an ECU (Electronic Control Unit). In such a case, the control unit 101 (ECU) and the voltage monitoring unit 102 may be separated by 1 m or more. Then, the control unit 101 (ECU) and the voltage monitoring unit 102 are connected with a long wiring exceeding 1 m, and the effect of saving the wiring connected with such a long wiring is great.

  Note that the notification signals 109-1, 109-2, and 109-3 are only required to be synchronized in pulse timing, and the synchronization method is not limited to the method using the reference signal 104.

  Next, for example, when an abnormality occurs only in the battery block 106-2, as shown in FIG. 10, only the notification signal 105-2, that is, the notification signal 109-2, has a pulse width of 2t. The pulse widths of 109-1 and 109-3 are t.

  When such notification signals 109-1, 109-2, 109-3 are logically ORed by the OR circuit 103, a combined notification signal 111 having a pulse width 2t and a period T is obtained as shown in FIG. Thus, according to the OR circuit 103, an abnormality occurs in at least one of the battery blocks 106-1, 106-2, and 106-3, and at least one of the notification signals 109-1, 109-2, and 109-3. When one pulse width becomes a pulse width different from the normal pulse width t, for example, 2t, the pulse width of the combined notification signal 111 also becomes a pulse width different from the normal pulse width t, for example, 2t.

  Thus, only when all of the battery blocks 106-1, 106-2, 106-3 are normal, the composite notification signal 111 becomes a pulse signal having a pulse width t and a period T, and the battery blocks 106-1, 106-2. , 106-3 becomes abnormal, the composite notification signal 111 becomes a pulse signal having a pulse width 2t and a period T.

  The synthesis notification signal 111 obtained in this way is output from the OR circuit 103 to the control unit 101 and received by the control unit 101. Then, based on the synthesis notification signal 111, the control unit 101 recognizes whether there is a voltage abnormality in the battery blocks 106-1, 106-2, 106-3 and whether there is a disconnection or an abnormality in the OR circuit 103 (step S7). ).

  Specifically, when the synthesis notification signal 111 shown in FIG. 9 is input to the control unit 101 shown in FIG. 6, the reference signal 110 and the synthesis notification signal 111 are exclusive ORed by the exclusive OR gate EOR. Is done. Then, when all of the battery blocks 106-1, 106-2, 106-3 are normal, the reference signal 110 and the synthesis notification signal 111 have the same signal waveform, and therefore the output signal of the exclusive OR gate EOR is , Remain low level.

  Then, the output of the flip-flop FF2, that is, the battery abnormality detection signal Eb is maintained at the low level, and it is determined that all of the battery blocks 106-1, 106-2, and 106-3 are normal.

  On the other hand, if at least one of the battery blocks 106-1, 106-2, 106-3 becomes abnormal, the pulse width of the composite notification signal 111 becomes 2t as shown in FIG. 10, which is different from the pulse width of the reference signal 110. Occurs. Then, when the signal level differs between the synthesis notification signal 111 and the reference signal 110, that is, when the synthesis notification signal 111 is at the high level and the reference signal 110 is at the low level, the output signal of the exclusive OR gate EOR is high. At the rising edge, the flip-flop FF2 is latched to the high level, and the output signal of the flip-flop FF2, that is, the battery abnormality detection signal Eb becomes the high level.

  As a result, it is determined that at least one of the battery blocks 106-1, 106-2, 106-3 has become abnormal.

  In addition, although the control part 101 showed the example which determines whether the pulse width of the pulse of the composite notification signal 111 is the pulse width t by comparing the composite notification signal 111 with the reference signal 110, Of course, it is possible to determine whether or not the pulse width is the pulse width t by measuring the pulse width of the pulse of the synthesis notification signal 111 without using the signal 110.

  If the pulse width of the composite notification signal 111 output from the OR circuit 103 is the pulse width t, the control unit 101 determines that there is no abnormality in the battery blocks 106-1, 106-2, and 106-3. To do. In addition, when the pulse width of the composite notification signal 111 is different from the pulse width t, for example, 2t, the control unit 101 generates an abnormality in at least one of the battery blocks 106-1, 106-2, and 106-3. It is determined that

  In this way, the notification signals 109-1, 109-2, and 109-3 from the voltage monitoring units 102-1, 102-2, and 102-3 are combined by the OR circuit 103, and the combined notification signal 111 is generated by the control unit 101. Thus, the control unit 101 can detect that an abnormality has occurred in at least one of the battery blocks 106-1, 106-2, and 106-3 while reducing wiring.

  Further, when the OR circuit 103 fails or a disconnection occurs between the OR circuit 103 and the control unit 101 and the pulse of the composite notification signal 111 cannot be obtained by the control unit 101, the counter CT is set as described above. By counting up, the control unit 101 detects that the error signal Ew is at a high level so that the OR circuit 103 is broken or a disconnection occurs between the OR circuit 103 and the control unit 101. Can be done.

  Here, as described above, when the power supply device 113 is used as a power source for a vehicle such as an electric vehicle or a hybrid vehicle, a long wiring exceeding 1 m is provided between the control unit 101 (ECU) and the OR circuit 103. There is a great merit that it is possible to detect disconnection of this wiring portion.

  Even when the OR circuit 103 fails or the signal path from the OR circuit 103 to the control unit 101 is disconnected, and the composite notification signal 111 remains at a low level, the composite notification signal 111 is also the reference. Since a pulse having the same pulse width t as that of the signal 110 is not included, the output signal of the exclusive OR gate EOR becomes high level, and the battery abnormality detection signal Eb becomes high level.

  However, at this time, as described above, since the counter CT counts up, the error signal Ew also becomes high level. Therefore, when the battery abnormality detection signal Eb and the error signal Ew become high level, the OR circuit It can be determined that there is a failure of 103 or a disconnection between the OR circuit 103 and the control unit 101.

  The control unit 101 does not necessarily include the counter CT, and the signal path from the OR circuit 103 to the control unit 101 when the composite notification signal 111 does not include a pulse for a period exceeding the period T. It is not necessary to determine that an abnormality has occurred in at least a part of the OR circuit 103.

  For example, in the control unit 101 shown in FIG. 6, when the counter CT is not provided, not only when an abnormality occurs in at least one of the battery blocks 106-1, 106-2, and 106-3, Even when a failure occurs or a disconnection occurs between the OR circuit 103 and the control unit 101, the battery abnormality detection signal Eb is at a high level. It can be determined that some abnormality has occurred, such as an abnormality in the OR circuit 103 or a disconnection of the wiring.

  As described above, even when the counter CT is not provided, even if the composite notification signal 111 becomes low level due to disconnection, for example, the battery blocks 106-1, 106- 2,106-3 is not determined to be normal.

  When there is one voltage monitoring unit, the OR circuit 103 may not be provided, and the notification signal 109 may be output to the control unit 101 instead of the combined notification signal 111. Even in this case, the other effects excluding the wiring saving can be obtained in the same manner as when the control unit 101 determines abnormality based on the composite notification signal 111 output from the OR circuit 103.

  In addition, an example is shown in which a high-side pulse is used as a pulse included in the reference signal, the notification signal, and the combined notification signal, the pulse width is set, and a positive logic circuit is used. The pulse width may be set using, and a negative logic circuit may be used.

  In this embodiment, when an abnormality occurs, the voltage monitoring unit 102 generates a notification signal including a double pulse width. For example, as shown in FIG. 11, each voltage monitoring unit A notification signal including an abnormal pulse may be generated at the position set to 102. Specifically, the following may be performed.

  That is, the notification signal generation unit 121 outputs the reference signal 104 as it is as the notification signal 105 to the output insulating element 108 regardless of whether or not abnormality is detected by the voltage abnormality determination unit 122, so that the pulse width t and period T Generate a reference pulse. In addition, when the voltage abnormality determination unit 122 detects an abnormality, for example, when the detection signal Err is at a high level, the notification signal generation unit 121 outputs an abnormal pulse with a pulse width t, for example, at a timing different from the reference pulse. .

  Even in such a configuration, the control unit 101 differs from the reference pulse in the combined notification signal 111 in the same manner as when the voltage monitoring unit 102 generates a notification signal including a double pulse width when an abnormality occurs. When a pulse is included in the timing, the battery abnormality detection signal Eb can be set as an abnormal pulse. Therefore, the control unit 101 can determine the abnormality of the battery block 106, the occurrence of the above-described failure or disconnection.

  Furthermore, it is desirable to set in advance the output timings of the abnormal pulses of the notification signal generators 121 included in the voltage monitoring units 102-1, 102-2, and 102-3 so that they are different from each other. Then, the control unit 101 can count the number of battery blocks 106 in which an abnormality has occurred by counting the number of abnormal pulses included between the two reference pulses. In addition, the control unit 101 determines that an abnormality has occurred in the battery block 106 corresponding to the communication signal generation unit 121 in which the timing at which the abnormal pulse was included is set, whereby the battery block 106 in which the abnormality has occurred. Can be specified.

  FIG. 11 shows an example in which all notification signals 105 include abnormal pulses, that is, all secondary batteries 106 are abnormal.

  The abnormality detection circuit and the power supply device according to the present invention are not limited to vehicles such as electric cars and hybrid cars, but also include power generation equipment for homes, battery-equipped devices such as uninterruptible power supplies, portable personal computers and digital cameras, video The present invention can also be suitably used in electronic devices such as cameras and mobile phones, hybrid elevators, power systems that combine solar batteries and power generation devices with secondary batteries, and the like.

DESCRIPTION OF SYMBOLS 1 Abnormality detection circuit 101 Control part 101a Reference signal generation part 102 Voltage monitoring part 103 OR circuit 104,110 Reference signal 105,109 Notification signal 106 Battery block 107 Input insulation element 108 Output insulation element 111 Composite notification signal 112 Cell 113 Power supply device 121 Notification Signal Generation Unit 122 Voltage Abnormality Determination Unit A1 Logic Gate CT Counter EOR Exclusive OR Gate FF1, FF2 Flip Flop MUX Multiplexer OSC Oscillator T Period t Pulse Width CLK Clock Signal Eb Battery Abnormality Detection Signal Err Detection Signal Ew Error Signal

Claims (9)

A plurality of anomaly detectors for detecting an anomaly corresponding to each of a plurality of secondary batteries;
A plurality of notification signal generators which are provided corresponding to the plurality of abnormality detection units, respectively, and generate and output notification signals indicating the presence or absence of detection of the abnormality by the plurality of abnormality detection units;
A logical sum operation unit that outputs a signal obtained by logically summing the notification signals from the plurality of notification signal generation units;
A control unit for determining the presence or absence of abnormality of the secondary battery based on the ORed signal output from the OR operation unit;
Each of the notification signal generators is
When the corresponding abnormality detection unit does not detect an abnormality, a signal including a pulse having a preset first pulse width is generated as the notification signal at a preset period at a timing synchronized with each other. ,
When the corresponding abnormality detection unit detects an abnormality, the pulse width of the pulse in the notification signal is set to a second pulse width different from the first pulse width to generate the notification signal,
The controller is
When the pulse width of the pulse included in the logical sum signal is the first pulse width, it is determined that there is no abnormality in the plurality of secondary batteries, and the logical sum signal includes the first pulse width. An abnormality detection circuit comprising: determining that an abnormality has occurred in at least one of the secondary batteries when a pulse having a pulse width different from the pulse width is included. A plurality of anomaly detectors for detecting an anomaly corresponding to each of a plurality of secondary batteries;
A plurality of notification signal generators which are provided corresponding to the plurality of abnormality detection units, respectively, and generate and output notification signals indicating the presence or absence of detection of the abnormality by the plurality of abnormality detection units;
A logical sum operation unit that outputs a signal obtained by logically summing the notification signals from the plurality of notification signal generation units;
A control unit for determining the presence or absence of abnormality of the secondary battery based on the ORed signal output from the OR operation unit;
Each of the notification signal generators is
A signal including a preset reference pulse is generated as the notification signal at a preset period at a timing synchronized with each other,
When the corresponding abnormality detection unit detects an abnormality, in addition to the reference pulse, an abnormal pulse indicating an abnormality is included in the notification signal at a timing different from the reference pulse,
The control unit determines that the secondary battery has no abnormality when the logical sum signal includes the reference pulse and the abnormal pulse is not included, and the logical sum signal includes the An abnormality detection circuit characterized by determining that an abnormality has occurred in any of the secondary batteries when a reference pulse and the abnormal pulse are included. Each of the notification signal generators is
Preliminarily set corresponding to each of the notification signal generation units, the abnormal signal is included in the notification signal at different timings,
The controller is
When the abnormal pulse is included in the logical sum signal, an abnormality is detected in the secondary battery corresponding to the abnormality detection unit corresponding to the communication signal generation unit in which the timing at which the abnormal pulse was included is set. The abnormality detection circuit according to claim 2, wherein it is determined that the error occurs. Each of the notification signal generators is
Including the abnormal pulse in the notification signal at different timings;
The controller is
When the abnormal pulse is included in the logical sum signal, the number of abnormal pulses included between the reference pulse and the next reference pulse is defined as the number of secondary batteries in which an abnormality has occurred. The abnormality detection circuit according to claim 2, wherein the abnormality detection circuit counts. The controller is
The abnormality detection circuit according to any one of claims 1 to 4, wherein when the notification signal does not include a pulse, it is determined that some abnormality has occurred. The control unit reaches the control unit from the plurality of notification signal generation units and the plurality of notification signal generation units when a pulse exceeding the set period is not included in the logical sum signal. The abnormality detection circuit according to claim 5, wherein it is determined that an abnormality has occurred in at least a part of the signal path. A reference signal generation unit that generates a reference signal that repeats the pulse having the first pulse width at the set period;
The plurality of notification signal generation units,
The abnormality detection according to claim 1, wherein the notification signal is generated based on the reference signal generated by the reference signal generation unit so that pulses in the notification signal output from each other are synchronized with each other. circuit. A reference signal generator for generating a reference signal that repeats the reference pulse at the set period;
The plurality of notification signal generation units,
The reference pulses in the notification signals output from each other are synchronized with each other by generating the notification signal based on the reference signal generated by the reference signal generation unit. The abnormality detection circuit according to any one of the above. The abnormality detection circuit according to any one of claims 1 to 8,
A power supply device comprising: the secondary battery.

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