JP2010252594A - Power-storage device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power-storage device capable of distinguishing and determining abnormalities of a plurality of current detecting circuits. <P>SOLUTION: The power-storage device includes a first current detecting circuit 21 and a second current detecting circuit 23 which are connected in series to a first power-storage element 17 and a second power-storage element 19 connected in parallel and detect a first current I1 and a second current I2, respectively, a voltage detecting circuit 25 which detects a first power-storage element voltage V1, and a control circuit 27 connected to the current detecting circuits 21 and 23 and the voltage detecting circuit 25. The control circuit 27 reads in the first current I1 and the second current I2, and determines a first measured calculation difference Sc1 from a difference between a first current calculation value I1c calculated from a voltage change width ΔV1 of the first power-storage element voltage V1 during a prescribed period Δt and a capacity value C1 of the first power-storage element 17 and the first current I1. When a measured ratio D (=I1/I2) is less than a prescribed minimum Min or more than a prescribed maximum Max, the control circuit determines the first current detecting circuit 21 to be abnormal if the first measured calculation difference Sc1 is larger than a first prescribed value K1, and determines the second current detecting circuit 23 to be abnormal if the first measured calculation difference Sc1 is not larger. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a power storage device that supplies stored power to a load when necessary.

  In recent years, regenerative power obtained from a generator (alternator) when a vehicle is decelerated is charged in a power storage unit, and the regenerative power is discharged to a load such as a vehicle drive motor other than during deceleration, thereby achieving high efficiency. Equipment has been developed. In such a power storage device, in order to efficiently charge the regenerative power generated steeply, as the power storage unit, for example, a plurality of electric double layer capacitors excellent in rapid charge / discharge characteristics are connected in series, The capacitor block has a configuration in which a plurality of capacitor blocks are connected in parallel. Thereby, the electrical storage apparatus which ensured the voltage and capacity | capacitance required in order to charge the said regenerative electric power is realizable.

  Since the power storage device includes a plurality of capacitor blocks, a current detection circuit (current sensor) is provided for each capacitor block in order to detect a current flowing through each of the capacitor blocks. Therefore, in order to ensure high reliability of the power storage device, abnormality determination for a plurality of current detection circuits is important.

  For example, Patent Document 1 proposes a current detection device that can determine the abnormality of a plurality of current sensors. A block circuit diagram of such a current detection device is shown in FIG.

  A control device 111 that performs various controls of the vehicle operates when power from the battery 112 is supplied through the key switch 113. The ignition device 114 and the injection device 115 are controlled by the operation of the control device 111, and the engine (not shown) is driven. Further, the battery 112 is charged by controlling the generator 116 connected to the engine. At this time, since the charge / discharge current of the battery 112 is detected by the current sensor 117, the control device 111 controls the generator 116 so that the state of charge of the battery 112 obtained from the output of the current sensor 117 becomes the target value. ing.

  Further, an air-fuel ratio sensor 118 that detects an air-fuel ratio of exhaust gas from the engine is connected to the control device 111. The air-fuel ratio sensor 118 includes a sensor element 119 that generates an output proportional to the air-fuel ratio, and a heater 120 that heats and activates the sensor element. The heater 120 includes a heater current detection circuit 121 for detecting the current in the controller 111. The control device 111 is also connected to a backup RAM 122 that stores abnormality diagnosis information and the like.

  Next, the abnormality determination operation of the current sensor 117 and the heater current detection circuit 121 in such a current detection device will be described.

  The control device 111 repeats the on / off operation of the heater 120 in order to control the sensor element 119 to a constant temperature. At this time, the control device 111 obtains, for example, the battery current change amount ΔIbat and the heater current change amount ΔIsen immediately before and immediately after the heater 120 is turned off from the outputs of the current sensor 117 and the heater current detection circuit 121, respectively. Next, the ratio between the two is calculated, and the tolerance K is calculated by subtracting one. That is, the tolerance K is obtained from K = ΔIbat / ΔIsen−1. If this tolerance K is not within the predetermined range, it is determined that either the current sensor 117 or the heater current detection circuit 121 is abnormal.

JP 2006-208126 A

  According to the current detection device described above, it can be determined that either the current sensor 117 or the heater current detection circuit 121 is abnormal. However, it is not possible to distinguish and determine which of the two is abnormal. . Therefore, when the abnormality determination operation by the current detection device is applied to a power storage device having a plurality of capacitor blocks, it is possible to determine abnormality of any of the current detection circuits connected to them. Since it is impossible to distinguish whether the detection circuit is abnormal, it is necessary to replace all the capacitor blocks when repairing, and there is a problem that wasteful replacement of normal capacitor blocks occurs.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object thereof is to provide a power storage device that can be efficiently repaired by distinguishing and judging abnormality of a plurality of current detection circuits.

  In order to solve the conventional problem, a power storage device according to the present invention includes a first power storage element and a second power storage element that are electrically connected in parallel, and a first power storage element that is connected in series to the first power storage element. A first current detection circuit for detecting a first current (I1) flowing through the second storage element, a second current detection circuit connected in series to the second storage element, and detecting a second current (I2) flowing through the second storage element; A voltage detection circuit that is electrically connected to both ends of the first storage element or the second storage element and detects the storage element voltage (V1); the first current detection circuit; the second current detection circuit; A control circuit electrically connected to a detection circuit, wherein the control circuit reads the detected first current (I1) and second current (I2), and stores the storage element in a predetermined period (Δt) Voltage change of voltage (V1) Based on (ΔV1), a first current calculation value (I1c) and / or a second current calculation value (I2c) is obtained, and a first correlation value between the first current (I1) and the second current (I2). , A second correlation value between the first current (I1) and the first current calculation value (I1c), or a third correlation value between the second current (I2) and the second current calculation value (I2c). It has a determination means for distinguishing and determining an abnormality in the first current detection circuit and the second current detection circuit from any two combinations.

  In addition, the power storage device of the present invention includes a first power storage element and a second power storage element that are electrically connected in parallel, and a first current (I1) that is connected in series to the first power storage element and flows through the first power storage element. A first current detection circuit that detects the current, a second current detection circuit that is connected in series to the second power storage element and detects a second current (I2) flowing through the second power storage element, and the first power storage element or the A voltage detection circuit that is electrically connected to both ends of the second storage element and detects the storage element voltage (V1), and is electrically connected to the first current detection circuit, the second current detection circuit, and the voltage detection circuit. The control circuit integrates the first current (I1) and the second current (I2) detected in the predetermined period (Δt), thereby integrating the first charge amount (Q1) and the second current amount (Q1). While calculating 2 charge amount (Q2) Based on the voltage change width (ΔV1) of the storage element voltage (V1) in the predetermined period (Δt), a first charge amount calculated value (Q1c) and / or a second charge amount calculated value (Q2c) are obtained, A first correlation value between the first charge amount (Q1) and the second charge amount (Q2), a second correlation value between the first charge amount (Q1) and the first charge amount calculation value (Q1c), or An abnormality in the first current detection circuit and the second current detection circuit is determined from any two combinations of the third correlation values of the second charge amount (Q2) and the second charge amount calculation value (Q2c). It has a judgment means to judge separately.

  According to the power storage device of the present invention, each capacitor block (first power storage element, second power storage element) is distinguished from the abnormality of the provided current detection circuit (first current detection circuit, second current detection circuit). Since it can be determined, it is possible to obtain an effect that highly efficient repair can be performed by replacing only the capacitor block having an abnormality.

  Further, by making an abnormality determination based on each charge amount (first charge amount Q1, second charge amount Q2, first charge amount calculated value Q1c and second charge amount calculated value Q2c), the influence of noise can be reduced, Since the abnormality of the current detection circuit can be distinguished and determined with higher accuracy, an effect of improving the accuracy of highly efficient repair can be obtained.

1 is a block circuit diagram of a power storage device according to Embodiment 1 of the present invention. Flowchart for performing abnormality determination in the current detection circuit of the power storage device in Embodiment 1 of the present invention Flowchart for performing abnormality determination in the current detection circuit of the power storage device in Embodiment 2 of the present invention Block circuit diagram of a power storage device in Embodiment 3 of the present invention The flowchart which performs abnormality determination in the electric current detection circuit of the electrical storage apparatus in Embodiment 3 of this invention Flowchart for performing abnormality determination in current detection circuit of power storage device in Embodiment 4 of the present invention Flowchart for performing abnormality determination in current detection circuit of power storage device in Embodiment 5 of the present invention Block circuit diagram of a conventional current detector

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. Here, a case where the power storage device is applied to a vehicle will be described.

(Embodiment 1)
1 is a block circuit diagram of a power storage device according to Embodiment 1 of the present invention. FIG. 2 is a flowchart for performing abnormality determination in the current detection circuit of the power storage device according to Embodiment 1 of the present invention. In FIG. 1, the thick line indicates the power system wiring, and the thin line indicates the signal system wiring.

  In FIG. 1, a power storage device 10 is connected via a charge / discharge circuit 11 to a generator 13 mechanically connected to a vehicle engine (not shown) and a load 15 which is an electrical component through power system wiring. Yes. The charge / discharge circuit 11 controls charge / discharge of the power storage device 10. The load 15 includes a motor that drives the vehicle. In the first embodiment, the generator 13 and the motor are separated from each other, but may be integrated.

  The power storage device 10 has the following configuration. First, the 1st electrical storage element 17 and the 2nd electrical storage element 19 which store electric power are connected so that it may become an electrical parallel circuit. This parallel circuit is connected to the charge / discharge circuit 11. Here, both the 1st electrical storage element 17 and the 2nd electrical storage element 19 have the structure which connected the some electric double layer capacitor in series. Therefore, each of the first power storage element 17 and the second power storage element 19 constitutes a capacitor block. Hereinafter, the two capacitor blocks are referred to as a first power storage element 17 and a second power storage element 19. Although the number of capacitor blocks may be more than two, the case of two is described here. Further, the capacitance value C1 of the first electricity storage element 17 and the capacitance value C2 of the second electricity storage element 19 are configured to be equal within the measurement error range.

  A first current detection circuit 21 and a second current detection circuit 23 are connected in series to the first storage element 17 and the second storage element 19, respectively. The first current detection circuit 21 has a function of detecting and outputting the first current I1 flowing through the first power storage element 17, and the second current detection circuit 23 is detecting and outputting the second current I2 flowing through the second power storage element 19. As the configurations of the first current detection circuit 21 and the second current detection circuit 23, in the first embodiment, a configuration including a shunt resistor and a peripheral circuit (not shown) such as an operational amplifier is used. The first current detection circuit 21 and the second current detection circuit 23 are not limited to the above-described configuration, and may be a magnetic detection configuration using a Hall element, for example.

  A voltage detection circuit 25 is electrically connected to both ends of the first power storage element 17. Here, as shown in FIG. 1, since one end (negative electrode) of the first power storage element 17 is connected to the ground, the voltage detection circuit 25 is connected to the ground and the other end (positive electrode) of the first power storage element 17. It is assumed to be configured. As a result, the voltage detection circuit 25 has a function of detecting and outputting the voltage across the first storage element 17, that is, the first storage element voltage V1. As a specific configuration of the voltage detection circuit 25, in the first embodiment, two series resistors are connected to both ends of the first power storage element 17, and the midpoint voltage is output as the first power storage element voltage V1. It was.

  The voltage detection circuit 25 is connected to both ends of the first power storage element 17, but the first power storage element 17 and the second power storage element 19 are connected in parallel. ) Is detected. Therefore, the voltage detection circuit 25 is electrically equivalent even if connected to both ends of the second power storage element 19, and therefore may be connected to either end of either the first power storage element 17 or the second power storage element 19. However, in order to detect the voltage with high reliability, it may be configured to connect to both of them. In the first embodiment, since the voltage detection circuit 25 is connected to both ends of the first power storage element 17, the power storage element voltage is hereinafter referred to as a first power storage element voltage V1.

  The control circuit 27 is electrically connected to the first current detection circuit 21, the second current detection circuit 23, and the voltage detection circuit 25 by signal system wiring. The control circuit 27 includes a microcomputer and peripheral circuits such as a memory. The control circuit 27 includes a first current I 1 detected by the first current detection circuit 21, a second current I 2 detected by the second current detection circuit 23, and a voltage detection circuit 25. The detected first storage element voltage V1 is read. Further, a control signal cont for controlling the charge / discharge circuit 11 is output. Further, the control circuit 27 is connected to a vehicle-side control circuit (not shown) by signal system wiring, and transmits and receives various signals by the data signal data.

  Next, the operation of the power storage device 10 will be described.

  First, the operation during normal vehicle travel will be described. When the vehicle is in a braking state from a running state, the vehicle-side control circuit controls the generator 13 to generate regenerative power, and at the same time, notifies the control circuit 27 that the vehicle is in a braking state by a data signal data. Send. In response to this, the control circuit 27 transmits a control signal cont to the charge / discharge circuit 11 so as to charge the first power storage element 17 and the second power storage element 19 with regenerative power. As a result, the regenerative power generated by the generator 13 is charged to the first power storage element 17 and the second power storage element 19 by the charge / discharge circuit 11. At this time, the control circuit 27 causes the charge / discharge circuit 11 so that the first current I1 detected by the first current detection circuit 21 and the second current I2 detected by the second current detection circuit 23 do not reach an overcurrent. To control.

  In this way, the control circuit 27 charges the first power storage element 17 and the second power storage element 19 with regenerative power, and the first power storage element voltage V1 detected by the voltage detection circuit 25 reaches a predetermined full charge voltage. Then, a control signal cont is transmitted to the charge / discharge circuit 11 so as to stop charging.

  With the above operation, the regenerative power generated during braking can be charged in the power storage device 11.

  Thereafter, when the vehicle stops or accelerates, the control circuit 27 receives a stop signal or acceleration signal from the vehicle-side control circuit as the data signal data. Thereby, the control circuit 27 transmits the control signal cont to the charge / discharge circuit 11 so as to discharge the regenerative power stored in the power storage device 10 to the load 15. As a result, regenerative power is supplied from the power storage device 10 to the load 15 via the charge / discharge circuit 11. With such an operation, while the power is supplied from the power storage device 10 to the load 15, power generation by the generator 13 is not necessary, so that the burden on the engine is reduced and fuel consumption can be reduced. At this time as well, the control circuit 27 reads the first current I1 and the second current I2 and monitors the overcurrent, and also reads the first power storage element voltage V1 to read the first power storage element 17 and the second power storage element 19. Is monitoring overdischarge.

  By repeating such an operation, the power storage device 10 collects the braking energy of the vehicle as regenerative electric power and supplies it to the load 15 during non-braking, whereby a highly efficient vehicle can be realized.

  Next, in the control circuit 27 of the power storage device 10 as described above, an operation for determining abnormality of the first current detection circuit 21, the second current detection circuit 23, and the voltage detection circuit 25, that is, a determination unit will be described with reference to FIG. I will explain. 2 is interrupted from a main routine (not shown) at a predetermined time interval (for example, 1 second) in the control circuit 27. Therefore, FIG. 2 is described as a subroutine.

  Further, the determination means is defined as the flowchart of FIG. 2 itself, and the main body that performs the operation is the control circuit 27. Therefore, in the following description, the control circuit 27 performs the operation performed by the determination means. Further, not limited to the first embodiment, all flowcharts in the following description are defined as determining means, and the operation is described as being performed by the control circuit 27.

  Further, since it is probabilistically low that the first current detection circuit 21 and the second current detection circuit 23 that are the targets of abnormality are abnormal at the same time, in all of the embodiments described below, a plurality of current detection circuits The operation for judging any of the above will be described. In all the embodiments, the abnormality of the voltage detection circuit 25 is also determined, but this also has a low probability of becoming abnormal at the same time as the first current detection circuit 21 and the second current detection circuit 23. An operation for determining abnormality in one of the detection circuit 21, the second current detection circuit 23, or the voltage detection circuit 25 will be described.

  When the subroutine of FIG. 2 is executed, the control circuit 27 first reads the first current I1 from the first current detection circuit 21 (step number S13). Next, the second current I2 is read from the second current detection circuit 23 (S17).

  Thereafter, it is determined whether or not the first current I1 is 0 and the second current I2 is 0 (S21). Thereby, it is judged whether the 1st electrical storage element 17 and the 2nd electrical storage element 19 are at the time of charging / discharging. The reason for making such a determination is that if both currents are zero, calculation of the actual measurement ratio D described later cannot be performed correctly. The determination that the first current I1 or the second current I2 is 0 is defined as a case where 0 is output within the detection accuracy of the first current detection circuit 21 or the second current detection circuit 23. In addition, when the first current detection circuit 21, the second current detection circuit 23, and the voltage detection circuit 25 are disconnected, their outputs are always 0, for example, and the behavior clearly differs from the normal output. The disconnection is detected in the main routine. Therefore, the subroutine of FIG. 2 is executed in a state where none of the first current detection circuit 21, the second current detection circuit 23, and the voltage detection circuit 25 has caused the disconnection abnormality.

  In S21, if both currents are 0 (Yes in S21), the first storage element 17 and the second storage element 19 are not charged / discharged, and the abnormality determination operation cannot be performed. End subroutine 2 and return to the interrupt source.

  On the other hand, if the first current I1 and the second current I2 are not 0 (No in S21), the first power storage element 17 and the second power storage element 19 are being charged / discharged. The first storage element voltage V1 is read from the voltage detection circuit 25 (S23). The first storage element voltage V1 is substituted into a temporary storage variable V1o by the memory (not shown) built in the control circuit 27 (S27). In addition, as described in S27 in FIG. 2, when V1o = V1 is described, it is defined below as an operation of substituting the value on the right side into the variable on the left side, except for the step of making a determination.

  Next, the control circuit 27 determines whether or not the predetermined period Δt has elapsed since the end of the operation of S27 (S29). Here, the predetermined period Δt is a period for obtaining a voltage change width ΔV1, which will be described later, and is experimentally obtained in advance and stored in the memory as a period in which the first current I1 and the second current I2 do not change greatly. It is. In the present embodiment, the predetermined period Δt is set to 0.01 seconds. Further, since the control circuit 27 has a built-in counter, the predetermined period Δt can be obtained thereby.

  If the predetermined period Δt has not elapsed (No in S29), the process returns to S29 and waits until the predetermined period Δt elapses.

  If the predetermined period Δt has elapsed (Yes in S29), the control circuit 27 reads the first storage element voltage V1 again from the voltage detection circuit 25 (S31).

  Next, the control circuit 27 obtains the voltage change width ΔV1 of the first storage element voltage V1 in the predetermined period Δt from ΔV1 = | V1o−V1 | (S35). From this voltage change width ΔV1, the predetermined period Δt, and the capacitance value C1 of the first power storage element 17, the control circuit 27 calculates the first current calculation value I1c from I1c = C1 · ΔV1 / Δt (S39). Here, as the capacitance value C1, an actual measurement value is obtained in advance and stored in the memory.

  Next, the control circuit 27 obtains a second correlation value between the first current I1 and the first current calculated value I1c. Specifically, the first actual measurement calculation difference Sc1 is obtained from Sc1 = | I1c−I1 | from the absolute value of the difference between the first current I1 read in S13 and the first current calculation value I1c (S41). This first actual measurement calculation difference Sc1 becomes the second correlation value. Further, a first correlation value between the first current I1 and the second current I2 is obtained. Specifically, an actual measurement ratio D between the first current I1 and the second current I2 is obtained from D = I1 / I2 (S43). This actual measurement ratio D becomes the first correlation value. Here, as described above, the capacitance value C1 of the first power storage element 17 and the capacitance value C2 of the second power storage element 19 are configured to be equal within the measurement error range, so the actual measurement ratio D is in the vicinity of 1. . Further, the order of obtaining the first correlation value (here, the actual measurement ratio D) and the second correlation value (here, the first actual measurement calculation difference Sc1) may be any first.

  Next, the control circuit 27 determines whether or not the actual measurement ratio D, which is the first correlation value, falls within the range from the predetermined minimum value Min to the predetermined maximum value Max (S45). Here, the normal value range of the actual measurement ratio D is set within ± 5% in consideration of measurement and calculation errors. Accordingly, the predetermined minimum value Min is determined to be 0.95 smaller by 5% than the normal value (= 1) of the actual measurement ratio D, and the predetermined maximum value Max is determined to be 1.05 larger by 5%. These values are stored in the memory.

  If the actual measurement ratio D is not less than the predetermined minimum value Min and not more than the predetermined maximum value Max, that is, if the actual measurement ratio D is 0.95 ≦ D ≦ 1.05 (Yes in S45), the control circuit 27 It is determined that both the first current detection circuit 21 and the second current detection circuit 23 are normal. In this case, the process jumps to S53 described later.

  On the other hand, when the actual measurement ratio D is less than the predetermined minimum value Min or exceeds the predetermined maximum value Max (No in S45), either the first current detection circuit 21 or the second current detection circuit 23 is abnormal. However, at this point, it cannot be determined which is abnormal.

  Therefore, the control circuit 27 determines whether the first actually measured calculation difference Sc1 that is the second correlation value is within the first predetermined range or exceeds it. Here, since the first actual calculation difference Sc1 is the absolute value of the difference between the first current calculation value I1c and the first current I1 (actual measurement value) from S41, the first actual calculation difference Sc1 exceeds the first predetermined range. If so, the calculated value and the actually measured value are deviated. The first predetermined range indicates a range from an upper limit value to a lower limit value of the first actually measured calculation difference Sc1 (corresponding to the deviation). Here, as described above, since the first actual measurement calculation difference Sc1 is obtained by the absolute value of the deviation, the lower limit value is zero. Therefore, as in the first embodiment, when the deviation is obtained as the first actual measurement calculation difference Sc1, the first predetermined range is from 0 (the lower limit value) to the upper limit value. Therefore, the operation of determining whether the first actual calculation difference Sc1 is within the first predetermined range or exceeds the first predetermined range is that the first actual calculation difference Sc1 is the upper limit value of the first predetermined range (hereinafter referred to as the first predetermined range). This is equivalent to determining whether the value is greater than (defined as the value K1).

  From the above, if No in S45, the control circuit 27 compares the first actual measurement calculation difference Sc1 with the first predetermined value K1 (S47). If the first actual measurement calculation difference Sc1 is larger than the first predetermined value K1 (Yes in S47), it can be determined that the first current detection circuit 21 is abnormal. The reason why such a determination can be made is as follows. Since the operation of S47 is performed when No in S45, either the first current detection circuit 21 or the second current detection circuit 23 is abnormal as described above. Therefore, as described above, the voltage detection circuit 25 is normal because the probability that the plurality of detection circuits become abnormal simultaneously is low. Therefore, when the deviation is large (Yes in S47), the first current detection circuit 21 is abnormal. In this case, the control circuit 27 outputs the abnormal signal of the first current detection circuit 21 as the data signal data to the vehicle side control circuit (S49). In response, the vehicle-side control circuit informs the driver that the first current detection circuit 21 is abnormal and prompts repair. Here, since it is known that the first current detection circuit 21 is abnormal, efficient repair is possible. In the first embodiment, the first predetermined value K1 (the upper limit value of the deviation) is defined as 5% of the maximum value of the first current I1 in consideration of the accuracy of measurement and calculation, and stored in the memory. It is.

  After S49, the subroutine of FIG. 2 is terminated and the process returns to the interrupt source.

  On the other hand, if the first actual measurement calculation difference Sc1 is equal to or smaller than the first predetermined value K1 (No in S47), it is understood that the first current detection circuit 21 is normal. However, if No in S45, either the first current detection circuit 21 or the second current detection circuit 23 is abnormal, so if No in S47, it is determined that the second current detection circuit 23 is abnormal. it can. In this case, the control circuit 27 outputs the abnormal signal of the second current detection circuit 23 as the data signal data to the vehicle control circuit (S51), ends the subroutine of FIG. 2, and returns to the interrupt source. From such an operation, the abnormality of the second current detection circuit 23 can be determined, so that efficient repair can be performed as in the case of the abnormality of the first current detection circuit 21.

  Here, returning to S45, if the actual measurement ratio D is not less than the predetermined minimum value Min and not more than the predetermined maximum value Max (Yes in S45), it is determined that the first current detection circuit 21 and the second current detection circuit 23 are normal. Therefore, next, the control circuit 27 compares the first actual measurement calculation difference Sc1 with the first predetermined value K1 as the first predetermined range (S53). Note that the value of the first predetermined value K1 here is the same as in S47. If the first actual measurement calculation difference Sc1 is less than or equal to the first predetermined value K1 (No in S53), the difference between the first current calculation value I1c and the first current I1, which is a normal value, is less than or equal to the first predetermined value K1. It will be. Therefore, the first current calculation value I1c is also calculated normally. Here, as described in S23 to S39, since the predetermined period Δt and the capacitance value C1 are constants, the first current calculation value I1c is a function of the first storage element voltage V1. Since the first current calculation value I1c is normally calculated, the first storage element voltage V1 is normally detected. Therefore, when the result in S53 is No, the control circuit 27 determines that the voltage detection circuit 25 is normal. In this case, since all of the first current detection circuit 21, the second current detection circuit 23, and the voltage detection circuit 25 are determined to be normal, the subroutine of FIG. 2 is terminated as it is, and the process returns to the interrupt source.

  On the other hand, if the first actual measurement calculation difference Sc1 is larger than the first predetermined value K1 (Yes in S53), the first current calculation value I1c is abnormal, so that the control circuit 27 obtains the first current calculation value I1c. It is determined that the voltage detection circuit 25 that has detected the necessary first storage element voltage V1 is abnormal. In this case, the control circuit 27 outputs the abnormal signal of the voltage detection circuit 25 as the data signal data to the vehicle side control circuit (S55), ends the subroutine of FIG. 2, and returns to the interrupt source.

  By operating in this way, not only can the abnormality of the first current detection circuit 21 and the second current detection circuit 23 be distinguished and determined, but also the abnormality of the voltage detection circuit 25 can be determined. As a result, more efficient repair is possible.

  The operation of the determination means described above is summarized as follows. The control circuit 27 reads the detected first current I1 and second current I2, and calculates the first current calculation value I1c based on the voltage change width ΔV1 of the first storage element voltage V1 in the predetermined period (Δt). The first current detection circuit and the second current detection are obtained from a first correlation value between the first current I1 and the second current I2 and a second correlation value between the first current I1 and the first current calculation value I1c. Judgment is made by distinguishing circuit abnormalities.

  With the above configuration and operation, it is possible to realize the power storage device 10 that can be efficiently repaired by distinguishing and determining abnormality of the plurality of current detection circuits.

  In the first embodiment, the actual measurement ratio D between the first current I1 and the second current I2 is used as the first correlation value. This is the absolute difference between the first current I1 and the second current I2. The actual difference S obtained from the value may be used. Here, the actual difference S is obtained from S = | I1−I2 |. Even when the actual measurement difference S is used as the first correlation value, the effect of distinguishing and determining abnormality of the plurality of current detection circuits is the same as when the actual measurement ratio D is used. However, the following points are different in operation.

  First, in FIG. 2, it is not necessary to determine whether or not both the first current I1 and the second current I2 are 0 in S21. This is because there is no possibility of dividing by 0 as in the case of the actual measurement ratio D. Next, in S43, instead of the actual measurement ratio D, the actual measurement difference S is obtained by the above equation. Next, in S45, it is determined whether or not the actual measurement difference S is within the range from the predetermined minimum value Min to the predetermined maximum value Max. Here, the predetermined minimum value Min and the predetermined maximum value Max are stored in the memory as values corresponding to the actually measured difference S. However, the actual measurement difference S greatly varies depending on the absolute values of the first current I1 and the second current I2. That is, if the absolute value is small, the actually measured difference S is small even if the first current detecting circuit 21 or the second current detecting circuit 23 is abnormal, and if the absolute value is large, the actually measured difference S is the first current detecting circuit. Even a difference within the measurement error range of the circuit 21 or the second current detection circuit 23 becomes large. Accordingly, the correlation between the predetermined minimum value Min and the predetermined maximum value Max may be obtained in advance according to the magnitude of the actually measured difference S, and for example, the correlation may be stored in the memory as a table. As a result, the optimum default minimum value Min and the default maximum value Max corresponding to the actual measurement difference S can be determined and then the determination of S45 can be performed. It becomes.

  In the first embodiment, as the second correlation value, the first actually measured calculation difference Sc1, which is the absolute value of the difference between the first current I1 and the first current calculation value I1c, is used. The first actual calculation ratio Dc1 obtained from the ratio between I1 and the first current calculation value I1c may be used. Here, the first actual measurement calculation ratio Dc1 is obtained from Dc1 = I1 / I1c. Even when the first actual measurement calculation ratio Dc1 is used as the second correlation value, the effect of distinguishing and determining abnormality of the plurality of current detection circuits is the same as when the first actual measurement calculation difference Sc1 is used. For the operation of FIG. 2, if the first actual calculation ratio Dc1 is obtained by the above equation in S41, the first predetermined value K1 in S47 and S53 is changed to the first predetermined range corresponding to the first actual calculation ratio Dc1. Good. That is, when the first actual measurement calculation ratio Dc1 is used, if it is normal as in the actual measurement ratio D, it becomes a value close to 1, so that the first actual calculation ratio Dc1 is ± in consideration of, for example, measurement or calculation errors. If it is determined that it is normal if it is in the range of 5%, the first predetermined range is in the range of 0.95 to 1.05. Therefore, in S47 and S53, it is only necessary to determine whether or not the first actual measurement calculation ratio Dc1 is within or exceeds the range of 0.95 to 1.05 (the first predetermined range). The first predetermined range corresponding to the first actual measurement calculation ratio Dc1 is also obtained in advance and stored in the memory. Further, when the first actual measurement calculation ratio Dc1 is used, the operation of S21 is necessary because there is a possibility of division by zero.

  Therefore, one of the actual measurement difference S or the actual measurement ratio D is selected as the first correlation value, and one of the first actual measurement calculation difference Sc1 or the first actual measurement calculation ratio Dc1 is selected as the second correlation value. It can be understood that any combination (four ways) may be used. That is, regardless of how the contents of the first correlation value and the second correlation value are combined, it is possible to distinguish and determine abnormality of the plurality of current detection circuits.

  In the first embodiment, the first current calculation difference I1c is obtained for the first power storage element 17, but this may be the second current calculation value I2c for the second power storage element 19. In this case, the calculation formula in S39 of FIG. 2 is I2c = C2 · ΔV1 / Δt. Here, C2 is a capacity value of the second power storage element 19. In this case, in S41, the first actual calculation difference Sc1 as the second correlation value is obtained, which is obtained by converting the second actual calculation difference Sc2 as the third correlation value into the second current I2 and the second current calculation value. What is necessary is just to obtain | require from the absolute value of a difference with I2c, ie, Sc2 = | I2c-I2 |. Further, although the capacitance value C1 of the first power storage element 17 and the capacitance value C2 of the second power storage element 19 are substantially equal to each other as described above, strictly speaking, there is a difference, and accordingly, S47 and S53 The first predetermined value K1 in this determination needs to be the second predetermined value K2 corresponding to the capacitance value C2 of the second power storage element 19. Therefore, in the determination of S47 and S53, the second actual calculation difference Sc2 is compared with the second predetermined value K2.

  However, when the abnormality determination is performed using the second actual measurement calculation difference Sc2, since the determination is made for the second current detection circuit 23, it is necessary to reverse the determination of S47 (Yes and No). That is, if the third correlation value (second measured calculation difference Sc2) is within the second predetermined range (second predetermined value K2), the second current detection circuit 23 is normal, and therefore the first current detection circuit 21 is Judge as abnormal. On the other hand, if the third correlation value (second actual measurement calculation difference Sc2) exceeds the second predetermined range (second predetermined value K2), the second current detection circuit 23 determines that it is abnormal. Note that the determination of S53 (Yes and No) may be as shown in FIG. 2 even when the third correlation value (second measured calculation difference Sc2) and the second predetermined range (second predetermined value K2) are compared.

  As described above, the abnormality determination may be performed from the first correlation value and the third correlation value with respect to the operation described in the flowchart of FIG. I understand that.

  Furthermore, as described above, the second correlation value may be selected from the first actual measurement calculation difference Sc1 or the first actual calculation calculation ratio Dc1, and the second correlation calculation difference may be used as the third correlation value. One of Sc2 and the second actual measurement calculation ratio Dc2 (Dc2 = I2 / I2c) may be selected.

  Further, in the configuration of FIG. 1 in the first embodiment, two capacitor blocks of the first power storage element 17 and the second power storage element 19 are used, but this is further compared to a configuration using a plurality of capacitor blocks. Is also applicable. That is, when there are three or more capacitor blocks, the abnormality detection of the current detection circuit described in the first embodiment is performed on any two capacitor blocks, and then the other two capacitor blocks are assigned. On the other hand, the operation of determining the abnormality of the current detection circuit may be repeated. In addition, when there are an odd number of capacitor blocks, the abnormality determination of the current detection circuits of any one capacitor block can be performed twice to determine the abnormality of the current detection circuits of all the capacitor blocks.

  Further, in the first embodiment, the first current I1 and the second current I2 are read only once immediately after the execution of the subroutine of FIG. 2, but this is performed while waiting for the elapse of the predetermined period Δt in S29. Each of them may be read repeatedly, and for example, each may be averaged after a predetermined period Δt has elapsed. In this case, although the calculation is more complicated than the operation of FIG. 2, the influence on the first current I1 and the second current I2 due to noise or the like can be reduced, and a highly accurate abnormality determination becomes possible.

  In the first embodiment, as described above, the first current I1 and the second current I2 are read only once immediately after the subroutine of FIG. 2 is executed. However, while the predetermined period Δt has elapsed, If there is a possibility that the regenerative power of the generator 13 or the power consumption of the load 15 changes suddenly and the charge / discharge current to the power storage device 10 suddenly changes or the charge and discharge are suddenly reversed, The first current calculation value I1c may be significantly different from a certain first current I1. In this case, it may be determined that the detection circuit is abnormal although all the detection circuits are normal. Therefore, in an application in which such a state is assumed, the first current I1 and the second current I2 are read again before executing S31 of the subroutine of FIG. 2, and at least one of these current values is read in S13 and S17. However, if the values of the first current I1 and the second current I2 exceed the predetermined range, or if the current value is reversed, the abnormality determination is stopped and the subroutine of FIG. 2 is terminated. Good. The range may be obtained from the sudden change width of the current in the actual usage environment of the power storage device 10.

(Embodiment 2)
FIG. 3 is a flowchart for performing abnormality determination in the current detection circuit of the power storage device according to Embodiment 2 of the present invention.

  In the second embodiment, the configuration is the same as that in FIG. Since the feature of the second embodiment is the operation, the operation will be described below.

  First, the operation during normal vehicle travel is the same as in the first embodiment.

  Next, the abnormality determination operation of the first current detection circuit 21, the second current detection circuit 23, and the voltage detection circuit 25 will be described with reference to FIG. The flowchart shown in FIG. 3 is also described as a subroutine. Also, in the subroutine of FIG. 3, the same step numbers are assigned to parts that perform the same operations as in the subroutine of FIG. 2, and detailed description thereof is omitted.

  First, the operations from S13 to S41 in FIG. 3 are the same as those in FIG. Next, the control circuit 27 obtains the second calculated current value I2c from the voltage change width ΔV1, the predetermined period Δt and the capacitance value C2 of the second power storage element 19 from I2c = C2 · ΔV1 / Δt (S63). Here, as with the capacitance value C1, the capacitance value C2 is obtained in advance as an actual measurement value and stored in the memory.

  Next, the control circuit 27 obtains a third correlation value between the second current I2 and the second current calculated value I2c. Specifically, the second actual measurement calculation difference Sc2 is obtained from Sc2 = | I2c−I2 | from the absolute value of the difference between the second current I2 read in S17 and the second current calculation value I2c (S65). The second actual measurement calculation difference Sc2 becomes the third correlation value.

  Next, the control circuit 27 compares the first actual calculation difference Sc1 as the second correlation value with the first predetermined value K1 as the first predetermined range (S67). The handling of the first predetermined value K1 as the first predetermined range is the same as that described in S47 of FIG. The specific value of the first predetermined value K1 is also the same as that in the first embodiment.

  Here, as described in the first embodiment, if the first actually measured calculation difference Sc1 is large in S67, the calculated value and the actually measured value are shifted. Therefore, if the first actual measurement calculation difference Sc1 is equal to or smaller than the first predetermined value K1 (No in S67), the deviation is small, and therefore the first current I1 and the first power storage necessary for obtaining the first actual measurement calculation difference Sc1. The element voltage V1 is correctly output. Therefore, it can be determined that the first current detection circuit 21 and the voltage detection circuit 25 are normal. In this case, the process jumps to S75 described later.

  On the other hand, if the first actually measured calculation difference Sc1 is larger than the first predetermined value K1 (Yes in S67), it is possible to determine that one of the first current detection circuit 21 and the voltage detection circuit 25 is abnormal because the deviation is large. Therefore, the control circuit 27 compares the second actual measurement calculation difference Sc2 with the second predetermined value K2 as the second predetermined range (S69). The handling of the second predetermined value K2 as the second predetermined range and the specific value thereof are the same as those of the first predetermined value K1. If the second actual calculation difference Sc2 is equal to or smaller than the second predetermined value K2 (No in S69), the deviation between the second current calculated value I2c and the second current I2 is equal to or smaller than the second predetermined value K2. . Therefore, as described above, on the assumption that a plurality of detection circuits do not become abnormal at the same time, the first storage element voltage V1 and the second current I2 necessary for obtaining the second current calculation value I2c are: Is also normal. Therefore, in the case of No in S69, the second current detection circuit 23 and the voltage detection circuit 25 are normal. Here, as described above, if Yes in S67, it can be determined that either the first current detection circuit 21 or the voltage detection circuit 25 is abnormal, but if No in S69, the second current detection circuit 23 and Since the voltage detection circuit 25 is normal, it can be determined here that the first current detection circuit 21 is abnormal. In this case, the control circuit 27 outputs the abnormal signal of the first current detection circuit 21 as the data signal data to the vehicle side control circuit (S71). In response to this, the vehicle-side control circuit notifies the driver that the first current detection circuit 21 is abnormal, so that efficient repair is possible. Thereafter, the subroutine of FIG. 3 is terminated and the process returns to the interrupt source.

  On the other hand, if the second actual calculation difference Sc2 is larger than the second predetermined value K2 (Yes in S69), the difference between the second current calculated value I2c and the second current I2 is larger than the second predetermined value K2. It can be seen that the second current detection circuit 23 or the voltage detection circuit 25 is abnormal. Here, in the case of Yes in S67, as described above, the first current detection circuit 21 or the voltage detection circuit 25 is abnormal. Based on these results and the assumption that a plurality of detection circuits do not become abnormal at the same time, the voltage detection circuit 25 determined to be abnormal in both S67 and S69 is abnormal. In this case, the control circuit 27 outputs the abnormal signal of the voltage detection circuit 25 as the data signal data to the vehicle control circuit (S73), ends the subroutine of FIG. 3, and returns to the interrupt source.

  Here, returning to S67, if the first actual calculation difference Sc1 is equal to or smaller than the first predetermined value K1 (No in S67), the control circuit 27 compares the second actual calculation difference Sc2 with the second predetermined value K2 (S75). ). If the second actual calculation difference Sc2 is equal to or smaller than the second predetermined value K2 (No in S75), the deviation between the second current calculated value I2c and the second current I2 is equal to or smaller than the second predetermined value K2. . Accordingly, as in the case of No in S69, the second current detection circuit 23 and the voltage detection circuit 25 are normal. Here, as described above, if the determination at S67 is No, it is determined that the first current detection circuit 21 and the voltage detection circuit 25 are normal, so the first current detection circuit 21 and the second current detection circuit 23 are normal. It can be determined that all the voltage detection circuits 25 are normal. In this case, the subroutine of FIG. 3 is terminated as it is, and the process returns to the interrupt source.

  On the other hand, if the second actual measurement calculation difference Sc2 is larger than the second predetermined value K2 (Yes in S75), the difference between the second current calculation value I2c and the second current I2 is larger than the second predetermined value K2, so that Yes in S69. As in the case of, either the second current detection circuit 23 or the voltage detection circuit 25 is abnormal. However, since it is No in S67 here, both the first current detection circuit 21 and the voltage detection circuit 25 are normal. Therefore, if the answer is YES in S75, it can be determined that the second current detection circuit 23 is abnormal. In this case, the control circuit 27 outputs the abnormal signal of the second current detection circuit 23 as the data signal data to the vehicle control circuit (S77), ends the subroutine of FIG. 3, and returns to the interrupt source.

  The above operations by the determination means are summarized as follows. When the second correlation value exceeds the first predetermined range (here, greater than the first predetermined value K1), the control circuit 27 determines that the third correlation value is within the second predetermined range (here, the second predetermined value K2 or less). If there is, the first current detection circuit 21 determines that there is an abnormality. On the other hand, if the third correlation value exceeds the second predetermined range (here, larger than the second predetermined value K2), the voltage detection circuit 25 determines that there is an abnormality. Further, if the second correlation value is within the first predetermined range (here, the first predetermined value K1 or less), the third correlation value exceeds the second predetermined range (here, larger than the second predetermined value K2). In this case, the second current detection circuit 23 determines that there is an abnormality. On the other hand, if the third correlation value is within the second predetermined range (here, the second predetermined value K2 or less), the first current detection circuit 21, the second current detection circuit 23, and the voltage detection circuit 25 are determined to be normal.

  With the above configuration and operation, it is possible to realize the power storage device 10 that can be efficiently repaired by distinguishing and determining abnormality of the plurality of current detection circuits.

  In the second embodiment, abnormalities in the first current detection circuit 21 and the second current detection circuit 23 are distinguished and determined based on the second correlation value and the third correlation value. The abnormality determination is performed based on the correlation value and the second correlation value or the combination of the first correlation value and the third correlation value. Therefore, the first correlation value between the first current I1 and the second current I2, the second correlation value between the first current I1 and the first current calculation value I1c, or the second current I2 and the second current calculation value. The abnormality of the first current detection circuit 21 and the second current detection circuit 23 can be distinguished and determined by any two combinations of the third correlation values with I2c. If the first correlation value and the second correlation value are combined, the first current calculation value I1c is calculated. If the first correlation value and the third correlation value are the combination, the second current calculation value I2c is calculated. However, in the case of a combination of the second correlation value and the third correlation value, it is necessary to calculate both the first current calculation value I1c and the second current calculation value I2c.

  In the second embodiment, the third correlation value is obtained as the second actual measurement calculation difference Sc2 obtained from the absolute value of the difference between the second current I2 and the second current calculation value I2c. Similarly to the case of the correlation value, the second actual measurement calculation ratio Dc2 between the second current I2 and the second current calculation value I2c may be used. Also in this case, the second predetermined range may be changed to, for example, the range described in the first embodiment (range of 0.95 to 1.05) according to the second actual measurement calculation ratio Dc2.

  Further, in the second embodiment, the abnormality determination is performed using the first actual calculation difference Sc1 as the second correlation value and the second actual calculation difference Sc2 as the third correlation value, respectively. As described in 1 and the second embodiment, the first actual calculation ratio Dc1 and the second actual calculation ratio Dc2 may be used as the first correlation value and the second correlation value, respectively. Therefore, in the second embodiment, there are four combinations of the second correlation value and the third correlation value, and a plurality of current detection circuits can be selected regardless of which combination is selected. It is possible to distinguish and judge the abnormality.

  From Embodiments 1 and 2 described above, in order to distinguish and determine abnormality of a plurality of current detection circuits, 3 is obtained by combining any one of the first correlation value, the second correlation value, and the third correlation value. There are two methods, and there are two methods for these correlation values: difference and ratio. Therefore, there are a total of 12 combinations of abnormality determination methods (there are 4 combinations of the difference and ratio of the correlation value, and 3 combinations of the first to third correlation values, so that 4 × 3 = 12 combinations). ) Will exist. Of these, any combination of the current detection circuits can be distinguished and determined in any combination.

(Embodiment 3)
FIG. 4 is a block circuit diagram of a power storage device according to Embodiment 3 of the present invention. FIG. 5 is a flowchart for performing abnormality determination in the current detection circuit of the power storage device according to Embodiment 3 of the present invention. In FIG. 4, the thick line indicates the power system wiring, and the thin line indicates the signal system wiring.

  In the configuration of the third embodiment shown in FIG. 4, the same components as those in FIG. That is, the feature of the configuration in the third embodiment is that a common temperature detector 29 is provided for first power storage element 17 and second power storage element 19 in FIG. Specifically, the temperature detector 29 is provided between the first power storage element 17 and the second power storage element 19. Thereby, both average temperature is detectable. As the temperature detector 29, a thermistor having high sensitivity to temperature (resistance value change) is used in the third embodiment. Further, the temperature detector 29 is electrically connected to the control circuit 27 through signal wiring, and the detected temperature T is read into the control circuit 27.

  Other configurations are the same as those in FIG.

  Next, the operation in the third embodiment will be described.

  First, since the operation during normal vehicle travel is the same as that of the first embodiment, detailed description thereof is omitted. That is, the operation of the determination means, which is a feature of the third embodiment, is an abnormality determination of the first current detection circuit 21, the second current detection circuit 23, and the voltage detection circuit 25, and FIG. It explains using. In the operation of FIG. 5, the same operation as that of FIG. 2 in the first embodiment is denoted by the same step number, and detailed description thereof is omitted. Further, the flowchart shown in FIG. 5 is also executed as a subroutine in the control circuit 27 because the interrupt is executed from the main routine at predetermined time intervals in the control circuit 27 as in FIG.

  When the subroutine of FIG. 5 is executed, the control circuit 27 first reads the temperatures T of the first power storage element 17 and the second power storage element 19 from the temperature detector 29 (S111). Next, the first current I1 is read from the first current detection circuit 21 (S13), but this operation is the same as in FIG.

  Next, the control circuit 27 corrects the first current I1 with the temperature T (S115). Here, since the first current detection circuit 21 detects the first current I1 by the shunt resistor, when the temperature T changes, the resistance value of the shunt resistor also changes accordingly. Accordingly, the first current I1, which is the output of the first current detection circuit 21, changes according to the temperature T. This change is caused by the first current I1 with respect to the temperature T obtained by experimentally obtaining in advance the resistance-temperature characteristics of the shunt resistance and the temperature characteristics of the circuits other than the shunt resistance in the first current detection circuit 21. The correlation is stored in the memory built in the control circuit 27. Therefore, the control circuit 27 can correct the temperature of the first current I1 from the correlation according to the temperature T read in S111.

  Next, the control circuit 27 reads the second current I2 from the second current detection circuit 23 (S17), and this operation is also the same as FIG. Next, the control circuit 27 corrects the second current I2 with the temperature T (S119). This correction method is the same as the method described in S115 for the first current I1, and the correlation between the temperature T and the second current I2. Correct based on the relationship.

  Next, operations in S21 and S23 are the same as those in FIG. Thereafter, the control circuit 27 corrects the first storage element voltage V1 read in S23 by the temperature T (S125). Here, the temperature correction method is the same as the correction method of the first current I1 described in S115, and the temperature T and the output of the voltage detection circuit 25 (first storage element voltage V1) obtained experimentally and stored in the memory in advance. It corrects based on the correlation.

  Next, the operations from S27 to S31 are the same as those in FIG. Thereafter, the control circuit 27 corrects the first storage element voltage V1 read in S31 by the temperature T (S133), but this operation is the same as S125.

  Next, the operation of S35 is the same as that in FIG. Thereafter, the control circuit 27 corrects the capacitance value C1 of the first power storage element 17 with the temperature T (S137). Here, since the correlation of the capacity value C1 with respect to the temperature T experimentally obtained in advance is stored in the memory, the capacity value C1 at the current temperature T is obtained using the correlation.

  Subsequent operations (S39 to S55) are the same as those in FIG.

  With the configuration and operation described above, the first current I1, the second current I2, the first storage element voltage V1, and the capacitance value C1 with respect to the temperature T are respectively determined according to the temperature T detected by the temperature detector 29. Since the correction is made from the correlation, it is possible to realize the power storage device 10 capable of distinguishing abnormality of the first current detection circuit 21, the second current detection circuit 23, and the voltage detection circuit 25 and determining with high accuracy.

  In the third embodiment, only one temperature detector 29 is provided in common for the first power storage element 17 and the second power storage element 19, but this temperature detector 29 is configured as the first power storage element. It is good also as a structure provided in at least one of 17 and the 2nd electrical storage element 19. FIG. That is, if the first power storage element 17 and the second power storage element 19 are arranged adjacent to each other, the temperatures of the first power storage element 17 and the second power storage element 19 can be regarded as substantially the same. Therefore, for example, the temperature detector 29 may be provided only in the first power storage element 17. Further, when the temperature detector 29 is provided in both the first power storage element 17 and the second power storage element 19, the temperature correction related to the first power storage element 17 (first current I1, first power storage element voltage V1, and The capacitance value C1) and the temperature correction (second current I2) related to the second power storage element 19 can be corrected according to the respective temperatures, so that a more accurate abnormality determination can be performed.

  Also in the third embodiment, the abnormality determination is performed using the actual measurement ratio D as the first correlation value and the first actual calculation difference Sc1 as the second correlation value. As described above, it is possible to distinguish and determine abnormality of a plurality of current detection circuits regardless of which combination is selected from the four combinations as the first correlation value and the second correlation value.

  Further, in the third embodiment, as described in the first embodiment, the third correlation value (for example, the second actually measured calculation difference Sc2) may be used instead of the second correlation value, or the second embodiment. As described above, the abnormality determination may be performed based on the second correlation value and the third correlation value.

  Also in the third embodiment, as described in the first embodiment, the operation of reading the first current I1 and the second current I2 is repeated for a predetermined period Δt in order to reduce the influence of noise. May be. However, in the third embodiment, the first current I1 and the second current I2 are corrected by the temperature T detected by the temperature detector 29. Therefore, the temperature may be corrected for each of the first current I1 and the second current I2 read during the predetermined period Δt. However, the temperature correction takes time, and the first current I1 and the second current I2 are sufficient. It may not be possible to read up to a certain number of times. In this case, the temperature correction may be performed on values obtained by averaging the first current I1 and the second current I2 after the lapse of the predetermined period Δt.

(Embodiment 4)
FIG. 6 is a flowchart for performing abnormality determination in the current detection circuit of the power storage device according to Embodiment 4 of the present invention.

  In the fourth embodiment, the configuration is the same as in FIG. Since the feature of the fourth embodiment is the operation, the operation will be described below.

  First, the operation during normal vehicle travel is the same as in the first embodiment.

  Next, the abnormality determination operation of the first current detection circuit 21, the second current detection circuit 23, and the voltage detection circuit 25 will be described with reference to FIG. The flowchart shown in FIG. 6 is also described as a subroutine.

  When the subroutine of FIG. 6 is executed, the control circuit 27 first reads the first storage element voltage V1 from the voltage detection circuit 25 (S213). The first storage element voltage V1 is substituted into the temporary storage variable V1o. At the same time, 0 is substituted into the first charge amount Q1 defined as a variable on the memory built in the control circuit 27 and cleared. Similarly, the second charge amount Q2, which is a variable on the memory, is substituted by 0 and cleared (S217).

  Thereafter, although not shown in FIG. 6, the counter described in the first embodiment is started in order to measure a predetermined period Δt described later.

  Next, the control circuit 27 reads the first current I1 from the first current detection circuit 21 (S219). Next, the second current I2 is read from the second current detection circuit 23 (S223).

  The first current I1 and the second current I2 read in this way are multiplied by the execution period dt and added to the first charge amount Q1 and the second charge amount Q2, respectively. That is, the product of the first current I1 and the execution period dt is added to the value of the first charge amount Q1, and the result is substituted into the first charge amount Q1. Similarly, the product of the second current I2 and the execution period dt is added to the second charge amount Q2, and the result is substituted into the second charge amount Q2 (S227 above). The execution period dt is a time interval when the first current I1 and the second current I2 are repeatedly read during a predetermined period Δt to be described later, and corresponds to a period during which the operations from S219 to S229 are performed. The execution period dt is obtained in advance from the calculation speed of the microcomputer and stored in the memory.

  Next, the control circuit 27 determines whether or not the predetermined period Δt has elapsed by the counter (S229). Here, the predetermined period Δt is a period for obtaining a voltage change width ΔV1, which will be described later, and is set to 1 second as a period in which charges are stored or released to some extent in the first power storage element 17 and the second power storage element 19. .

  If the predetermined period Δt has not elapsed (No in S229), the execution period dt is changed to the read values of the first current I1 and the second current I2 until the predetermined period Δt elapses after returning to S219. The operation of adding the value obtained by multiplying the values to the values of the first charge amount Q1 and the second charge amount Q2 is repeated. By operating in this manner, the time integration values of the first current I1 and the second current I2 due to charging / discharging of the first power storage element 17 and the second power storage element 19 are approximately obtained in the predetermined period Δt. These values correspond to the first charge amount Q1 and the second charge amount Q2.

  If the predetermined period Δt has elapsed (Yes in S229), the control circuit 27 reads the first storage element voltage V1 again from the voltage detection circuit 25 (S231).

  Thereafter, it is determined whether the obtained first charge amount Q1 is other than 0 and the second charge amount Q2 is other than 0 (S235). The reason for making such a determination is that if any charge amount is 0, calculation of the actual measurement ratio D described later cannot be performed correctly.

  The determination of S235 includes a case where the first current detection circuit 21 and the second current detection circuit 23 are disconnected, and the output is always 0, for example, and the behavior clearly differs from the normal output. Similar to the first embodiment, it can be detected by the main routine. However, in the fourth embodiment, even if the first current detection circuit 21 and the second current detection circuit 23 are normal, the charge is discharged from the charge or the charge is discharged from the discharge during the predetermined period Δt. The integral value (= charge amount) may be zero. Also in this case, it can be determined in S235.

  The determination that the first charge amount Q1 and the second charge amount Q2 are 0 is 0 within the range of the detection accuracy of the first current detection circuit 21 and the second current detection circuit 23 and the calculation error of time integration. Is defined as the output.

  In S235, if either the first charge amount Q1 or the second charge amount Q2 is 0 (No in S235), the abnormality determination operation cannot be performed. Therefore, the subroutine of FIG. Return.

  On the other hand, if neither the first charge amount Q1 nor the second charge amount Q2 is 0 (Yes in S235), the control circuit 27 sets the voltage change width ΔV1 of the first storage element voltage V1 in the predetermined period Δt as ΔV1 = | V1o−V1 | is obtained (S237). From this voltage change width ΔV1 and the capacitance value C1 of the first power storage element 17, the control circuit 27 obtains a first charge amount calculated value Q1c from Q1c = C1 · ΔV1 (S241). Here, as the capacitance value C1, an actual measurement value is obtained in advance and stored in the memory.

  Next, the control circuit 27 obtains a second correlation value between the first charge amount Q1 and the first charge amount calculated value Q1c. Specifically, the first actual measurement difference Sc1 is obtained from Sc = | Q1c−Q1 | from the absolute value of the difference between the first charge amount Q1 obtained in S227 and the first charge amount calculation value Q1c (S243). . This first actual measurement calculation difference Sc1 becomes the second correlation value. Further, a first correlation value between the first charge amount Q1 and the second charge amount Q2 is obtained. Specifically, an actual measurement ratio D between the first charge amount Q1 and the second charge amount Q2 is obtained from D = Q1 / Q2 (S245). This actual measurement ratio D becomes the first correlation value.

  The first correlation value (measured ratio D) and the second correlation value (first measured calculation difference Sc1) are obtained from the first current I1, the second current I2, and the first current calculated value I1c in the first embodiment. Instead, in the fourth embodiment, it is obtained from the first charge amount Q1, the second charge amount Q2, and the first charge amount calculated value Q1c.

  Here, as described in the first embodiment, the capacitance value C1 of the first power storage element 17 and the capacitance value C2 of the second power storage element 19 are configured to be equal within the measurement error range. D is in the vicinity of 1. In addition, the order of obtaining the first correlation value and the second correlation value may be either.

  Next, the control circuit 27 determines whether or not the actual measurement ratio D, which is the first correlation value, falls within the range from the predetermined minimum value Min to the predetermined maximum value Max (S247). Here, the default minimum value Min and the default maximum value Max are the same as those in the first embodiment.

  If the actual measurement ratio D is not less than the predetermined minimum value Min and not more than the predetermined maximum value Max (Yes in S247), the control circuit 27 indicates that both the first current detection circuit 21 and the second current detection circuit 23 are normal. Judge. In this case, the process jumps to S255 described later.

  On the other hand, if the actual measurement ratio D is less than the predetermined minimum value Min or exceeds the predetermined maximum value Max (No in S247), either the first current detection circuit 21 or the second current detection circuit 23 is abnormal. The control circuit 27 compares the first actual calculation difference Sc1 as the second correlation value with the first predetermined value K1 as the first predetermined range (S249). The first predetermined value K1 as the first predetermined range is handled in the same manner as in the first embodiment. If the first actual measurement difference Sc1 is larger than the first predetermined value K1 (Yes in S249), the first current detection circuit 21 can be determined to be abnormal for the reason described in the first embodiment. In this case, the control circuit 27 outputs the abnormal signal of the first current detection circuit 21 as the data signal data to the vehicle side control circuit (S251). Thereby, since it is known that the first current detection circuit 21 is abnormal, an efficient repair is possible. Note that the first predetermined value K1 in the fourth embodiment is an upper limit value of a difference (deviation) between the first charge amount Q1 and the first charge amount calculated value Q1c. For example, the accuracy of measurement and calculation is considered. And defined as 5% of the maximum value of the first charge amount Q1, and stored in the memory.

  After S251, the subroutine of FIG. 6 is terminated and the process returns to the interrupt source.

  On the other hand, if the first actual measurement calculation difference Sc1 is equal to or smaller than the first predetermined value K1 (No in S249), it can be determined that the second current detection circuit 23 is abnormal for the reason described in the first embodiment. In this case, the control circuit 27 outputs the abnormal signal of the second current detection circuit 23 as the data signal data to the vehicle side control circuit (S253), ends the subroutine of FIG. 6, and returns to the interrupt source. From such an operation, the abnormality of the second current detection circuit 23 can be determined, so that efficient repair can be performed as in the case of the abnormality of the first current detection circuit 21.

  Here, returning to S247, if the actual measurement ratio D is not less than the predetermined minimum value Min and not more than the predetermined maximum value Max (Yes in S247), it is determined that the first current detection circuit 21 and the second current detection circuit 23 are normal. Therefore, next, the control circuit 27 compares the first actual measurement calculation difference Sc1 with the first predetermined value K1 (S255). If the first actual measurement calculation difference Sc1 is equal to or smaller than the first predetermined value K1 (No in S255), the deviation between the first charge amount calculated value Q1c and the first charge amount Q1 that is the normal value is the first predetermined value. It will be below K1. Therefore, the first charge amount calculation value Q1c is also calculated normally. Here, as described in S241, since the capacitance value C1 is a constant, the first charge amount calculation value Q1c is a function of the first storage element voltage V1. Since the first charge amount calculated value Q1c is normally calculated, the first storage element voltage V1 is normally detected. Therefore, in the case of No in S255, the control circuit 27 determines that the voltage detection circuit 25 is normal. In this case, since all of the first current detection circuit 21, the second current detection circuit 23, and the voltage detection circuit 25 are determined to be normal, the subroutine of FIG. 6 is terminated as it is, and the process returns to the interrupt source.

  On the other hand, if the first actual calculation difference Sc1 is larger than the first predetermined value K1 (Yes in S255), the first charge amount calculation value Q1c is abnormal, and the control circuit 27 obtains the first charge amount calculation value Q1c. Therefore, it is determined that the voltage detection circuit 25 that detects the first storage element voltage V <b> 1 necessary for this is abnormal. In this case, the control circuit 27 outputs the abnormal signal of the voltage detection circuit 25 as the data signal data to the vehicle-side control circuit (S257), ends the subroutine of FIG. 6, and returns to the interrupt source.

  By operating in this way, not only can the abnormality of the first current detection circuit 21 and the second current detection circuit 23 be distinguished and determined, but also the abnormality of the voltage detection circuit 25 can be determined. As a result, more efficient repair is possible.

  Further, in the fourth embodiment, instead of the abnormality determination based on each current value (instantaneous value or average value) in the first embodiment, abnormality determination based on each charge amount (= integrated value) is performed. In this case, the integration period (= predetermined period Δt) is two orders of magnitude longer than that in the first embodiment, so that the influence of noise is greatly reduced. However, since the predetermined period Δt becomes longer, it takes time to determine abnormality. Therefore, the current value or the charge amount may be selected as appropriate according to the noise environment of the power storage device 10 and the allowable period of abnormality determination.

  Also in the fourth embodiment, when there are three or more capacitor blocks, as described in the first embodiment, the abnormality determination for any two capacitor blocks may be repeated.

  With the above configuration and operation, it is possible to realize the power storage device 10 capable of performing efficient and highly accurate repair by distinguishing and determining abnormalities of a plurality of current detection circuits with high accuracy even in a noisy environment. .

  In the fourth embodiment, the abnormality determination is performed using the actual measurement ratio D as the first correlation value and the first actual calculation difference Sc1 as the second correlation value. As described above, it is possible to distinguish and determine abnormality of a plurality of current detection circuits regardless of which combination is selected from the four combinations as the first correlation value and the second correlation value. In this case, if the combination does not require division, the operation of S235 is unnecessary.

  Further, in the fourth embodiment, as described in the first embodiment, a third correlation value (for example, the second actual calculation difference Sc2 with respect to the charge amount) may be used instead of the second correlation value. As described in the second embodiment, the abnormality determination may be performed based on the second correlation value and the third correlation value.

  In summary, the first correlation value between the first charge amount Q1 and the second charge amount Q2, the second correlation value between the first charge amount Q1 and the first charge amount calculated value Q1c, or the second charge amount Q2 The abnormality of the first current detection circuit and the second current detection circuit may be distinguished and determined from any two combinations of the third correlation values with the second charge amount calculation value Q2c.

  The detailed operation of the determination (including the operation described in the first embodiment) is summarized as follows. When the first correlation value is less than the predetermined minimum value Min or exceeds the predetermined maximum value Max, the control circuit 27 determines whether the second correlation value exceeds the first predetermined range or the third correlation value is within the second predetermined range. If so, the first current detection circuit 17 determines that there is an abnormality. On the other hand, if the second correlation value is within the first predetermined range or the third correlation value exceeds the second predetermined range, the second current detection circuit 19 determines that there is an abnormality. Furthermore, if the first correlation value is not less than the predetermined minimum value Min and not more than the predetermined maximum value Max, the first current detection circuit 17 and the second current detection circuit 19 are determined to be normal. When it is determined that the first current detection circuit 17 and the second current detection circuit 19 are normal, if the second correlation value exceeds the first predetermined range or the third correlation value exceeds the second predetermined range. The voltage detection circuit 25 determines that there is an abnormality. On the other hand, if the second correlation value is within the first predetermined range or the third correlation value is within the second predetermined range, the voltage detection circuit 25 determines that it is normal.

  Further, in the fourth embodiment, when an abnormality is determined using the second correlation value and the third correlation value as in the second embodiment, the following operation is performed. If the second correlation value exceeds the first predetermined range and the third correlation value is within the second predetermined range, the control circuit 27 determines that the first current detection circuit 17 is abnormal. On the other hand, if the third correlation value exceeds the second predetermined range, the voltage detection circuit 25 determines that it is abnormal. Furthermore, when the second correlation value is within the first predetermined range, if the third correlation value exceeds the second predetermined range, the second current detection circuit 19 determines that there is an abnormality. On the other hand, if the third correlation value is within the second predetermined range, the first current detection circuit 17, the second current detection circuit 19, and the voltage detection circuit 25 are determined to be normal.

  As is apparent from these operations, the operation for determining abnormality based on the amount of charge described in the fourth embodiment is substantially the same as the operation for determining abnormality based on the current value described in the first and second embodiments. Are equivalent.

(Embodiment 5)
FIG. 7 is a flowchart for performing abnormality determination in the current detection circuit of the power storage device according to Embodiment 5 of the present invention.

  In the fifth embodiment, the configuration is the same as that in FIG. Since the feature of the fifth embodiment is the operation, the operation will be described below.

  First, the operation during normal vehicle travel is the same as in the first embodiment.

  Next, the abnormality determination operation that characterizes the first current detection circuit 21, the second current detection circuit 23, and the voltage detection circuit 25 will be described with reference to FIG. In the operation of FIG. 7, the same operation as that of FIG. 6 in the fourth embodiment is denoted by the same step number, and detailed description thereof is omitted. Also in the flowchart shown in FIG. 7, as in FIG. 6, the control circuit 27 performs interrupt execution from the main routine at predetermined time intervals, so FIG. 7 is described as a subroutine.

  When the subroutine of FIG. 7 is executed, the control circuit 27 first reads the temperatures T of the first power storage element 17 and the second power storage element 19 from the temperature detector 29 (S311). Next, the first storage element voltage V1 is read from the voltage detection circuit 25 (S213), and this operation is the same as in FIG.

  Next, the control circuit 27 corrects the first storage element voltage V1 with the temperature T (S315). This temperature correction is performed based on the correlation with the temperature T as described in the third embodiment.

  Next, the operations in S217 and S219 are the same as those in FIG. Thereafter, the control circuit 27 corrects the first current I1 read in S219 with the temperature T (S321). This correction method is also the same as in the third embodiment.

  Next, the control circuit 27 reads the second current I2 from the second current detection circuit 23 (S223), and this operation is also the same as in FIG. Next, the control circuit 27 corrects the second current I2 with the temperature T (S325). This correction method is also the same as in the third embodiment. Here, the temperature correction is performed every time the first current I1 and the second current I2 are read. This is because the predetermined period Δt is two orders of magnitude larger than that of the first embodiment, so that the temperature correction is performed each time. Can be read a sufficient number of times.

  Next, the operations from S227 to S231 are the same as those in FIG. Thereafter, the control circuit 27 corrects the first storage element voltage V1 read in S231 by the temperature T (S333). This correction method is also the same as S315.

  Next, the operations in S235 and S237 are the same as those in FIG. Thereafter, the control circuit 27 corrects the capacitance value C1 of the first power storage element 17 with the temperature T (S339). This correction method is also the same as in the third embodiment.

  Subsequent operations (S241 to S257) are the same as those in FIG.

  With the above-described configuration and operation, the first current I1, the second current I2, the first storage element voltage V1, and the capacitance value C1 with respect to the temperature T are respectively determined according to the temperature T detected by the temperature detector 29. In addition to being corrected from the correlation, abnormality determination is performed based on the amount of charge, so that even in a noisy environment, the abnormality of the first current detection circuit 21, the second current detection circuit 23, and the voltage detection circuit 25 is distinguished and increased. The power storage device 10 that can be accurately determined can be realized.

  In the fifth embodiment, similarly to the third embodiment, the temperature detector 29 may be provided in at least one of the first power storage element 17 and the second power storage element 19, or the first power storage element 17. The temperature detector 29 may be provided in both the second storage element 19 and the second storage element 19.

  Also in the fifth embodiment, abnormality determination is performed using the actual measurement ratio D as the first correlation value and the first actual calculation difference Sc1 as the second correlation value. As described above, it is possible to distinguish and determine abnormality of a plurality of current detection circuits regardless of which combination is selected from the four combinations as the first correlation value and the second correlation value.

  Also in the fifth embodiment, as described in the fourth embodiment, the third correlation value may be used in place of the second correlation value, or an abnormality is determined based on the second correlation value and the third correlation value. May be performed.

  In the first and third embodiments, the abnormality determination of the voltage detection circuit 25 is performed after S53 of the subroutine of FIGS. 2 and 5. For example, the abnormality determination is separately performed in the main routine or another subroutine. In the case of a configuration to be performed, it may be omitted. In this case, if any of the subroutines in FIGS. 2 and 5 is Yes in S45, the subroutine is terminated as it is, and the process returns to the interrupt source. In the case where the abnormality determination is separately performed in the main routine and other subroutines with respect to the second embodiment, S73 of the subroutine in FIG. 3 is omitted, and if Yes in S69, the subroutine is terminated as it is, and the interrupt is interrupted. Return to the original.

  Similarly, also in the fourth and fifth embodiments, the abnormality determination (after S255) of the voltage detection circuit 25 in the subroutine of FIGS. 6 and 7 may be performed by the main routine or the like. In this case, if any of the subroutines in FIGS. 6 and 7 is Yes in S247, the subroutine may be terminated as it is, and the process returns to the interrupt source.

  In the first to fifth embodiments, the numerator and the denominator may be reversed in the calculation formulas of the actual measurement ratio D, the first actual calculation ratio Dc1, and the second actual calculation ratio Dc2. In this case, the predetermined minimum value Min, the predetermined maximum value Max, the first predetermined range, and the second predetermined range may be appropriately changed according to the case where the numerator and the denominator are reversed.

  In the first to fifth embodiments, the electric double layer capacitor is used for the first power storage element 17 and the second power storage element 19, but this may be a large capacity capacitor such as an electrochemical capacitor.

  Further, a secondary battery having a characteristic that the charge / discharge voltage changes with time in the actual use voltage range, such as a nickel metal hydride battery or a lithium ion battery, may be used for the first power storage element 17 and the second power storage element 19. . However, particularly when the time-dependent characteristics of the charge / discharge voltage are nonlinear, such as in a nickel metal hydride battery, the capacitance value C1 is not constant. What is necessary is just to correct | amend the capacitance value C1 from the present 1st electrical storage element voltage V1.

  In the first to fifth embodiments, the case where the power storage device 10 is applied to a vehicle has been described. However, the present invention is not limited thereto, and devices such as construction machines and elevators that charge and discharge regenerative power, and emergency power supplies You may apply as an electrical storage part.

  Since the power storage device according to the present invention can be repaired efficiently by distinguishing and judging abnormality of a plurality of current detection circuits, a plurality of capacitor blocks are provided to supply stored power to a load when necessary. It is useful as a power storage device or the like.

DESCRIPTION OF SYMBOLS 10 Power storage device 17 1st electrical storage element 19 2nd electrical storage element 21 1st electric current detection circuit 23 2nd electric current detection circuit 25 Voltage detection circuit 27 Control circuit 29 Temperature detector

Claims (16)

A first power storage element and a second power storage element electrically connected in parallel;
A first current detection circuit connected in series to the first power storage element and detecting a first current (I1) flowing through the first power storage element;
A second current detection circuit connected in series to the second power storage element and detecting a second current (I2) flowing through the second power storage element;
A voltage detection circuit that is electrically connected to both ends of the first storage element or the second storage element and detects the storage element voltage (V1);
A control circuit electrically connected to the first current detection circuit, the second current detection circuit, and the voltage detection circuit;
The control circuit reads the detected first current (I1) and second current (I2), and based on a voltage change width (ΔV1) of the storage element voltage (V1) in a predetermined period (Δt), Obtaining a first calculated current value (I1c) and / or a second calculated current value (I2c);
A first correlation value between the first current (I1) and the second current (I2), a second correlation value between the first current (I1) and the first current calculation value (I1c), or the second Determination means for distinguishing and determining abnormality of the first current detection circuit and the second current detection circuit from any two combinations of the third correlation values of the current (I2) and the second current calculation value (I2c) A power storage device. The determination means, when the first correlation value is less than a predetermined minimum value (Min) or exceeds a predetermined maximum value (Max),
If the second correlation value exceeds a first predetermined range or the third correlation value is within a second predetermined range, the first current detection circuit determines that an abnormality is present;
If the second correlation value is within the first predetermined range or if the third correlation value exceeds the second predetermined range, the second current detection circuit determines that the abnormality is present,
If the first correlation value is not less than the predetermined minimum value (Min) and not more than the predetermined maximum value (Max), the first current detection circuit and the second current detection circuit are determined to be normal. The power storage device according to claim 1. When the determination means determines that the first current detection circuit and the second current detection circuit are normal,
If the second correlation value exceeds the first predetermined range or the third correlation value exceeds the second predetermined range, the voltage detection circuit determines that an abnormality is present;
3. The voltage detection circuit according to claim 2, wherein the voltage detection circuit determines that the second correlation value is within the first predetermined range or the third correlation value is within the second predetermined range. Power storage device. The determination means, when the second correlation value exceeds a first predetermined range,
If the third correlation value is within the second predetermined range, the first current detection circuit determines that it is abnormal,
If the third correlation value exceeds the second predetermined range, it is determined that the voltage detection circuit is abnormal,
When the second correlation value is within the first predetermined range,
If the third correlation value exceeds the second predetermined range, the second current detection circuit determines that it is abnormal,
2. The power storage device according to claim 1, wherein if the third correlation value is within the second predetermined range, the first current detection circuit, the second current detection circuit, and the voltage detection circuit are determined to be normal. . The first correlation value is a measured difference (S) obtained from an absolute value of a difference between the first current (I1) and the second current (I2), or the first current (I1) and the first current (I1) The power storage device according to claim 1, which is an actual measurement ratio (D) with respect to the second current (I2). The second correlation value is a first actually measured calculation difference (Sc1) obtained from an absolute value of a difference between the first current (I1) and the first current calculation value (I1c), or the first current ( The power storage device according to claim 1, wherein the power storage device is a first actual measurement calculation ratio (Dc1) between I1) and a first current calculation value (I1c). The third correlation value is a second actually calculated difference (Sc2) obtained from an absolute value of a difference between the second current (I2) and a second current calculated value (I2c), or the second current ( The power storage device according to claim 1, which is a second actual measurement calculation ratio (Dc2) between I2) and the second current calculation value (I2c). At least one of the first power storage element and the second power storage element is provided with a temperature detector electrically connected to the control circuit, or the first power storage element electrically connected to the control circuit And a common temperature detector for the second power storage element,
The determination means determines the first current (I1), the second current (I2), and the storage element voltage (V1) with respect to the temperature (T) according to the temperature (T) detected by the temperature detector. The power storage device according to claim 1, wherein correction is performed from each correlation. A first power storage element and a second power storage element electrically connected in parallel;
A first current detection circuit connected in series to the first power storage element and detecting a first current (I1) flowing through the first power storage element;
A second current detection circuit connected in series to the second power storage element and detecting a second current (I2) flowing through the second power storage element;
A voltage detection circuit that is electrically connected to both ends of the first storage element or the second storage element and detects the storage element voltage (V1);
A control circuit electrically connected to the first current detection circuit, the second current detection circuit, and the voltage detection circuit;
The control circuit integrates the first current (I1) and the second current (I2) detected in the predetermined period (Δt) to obtain the first charge amount (Q1) and the second charge amount (Q2). And calculating the first charge amount calculated value (Q1c) and / or the second charge amount calculated value (Q2c) based on the voltage change width (ΔV1) of the storage element voltage (V1) in the predetermined period (Δt). Seeking
A first correlation value between the first charge amount (Q1) and the second charge amount (Q2); a second correlation value between the first charge amount (Q1) and the first charge amount calculated value (Q1c); Alternatively, from any two combinations of the third correlation values of the second charge amount (Q2) and the second charge amount calculated value (Q2c), the abnormality of the first current detection circuit and the second current detection circuit is determined. A power storage device having determination means for distinguishing and determining. The determination means, when the first correlation value is less than a predetermined minimum value (Min) or exceeds a predetermined maximum value (Max),
If the second correlation value exceeds a first predetermined range or the third correlation value is within a second predetermined range, the first current detection circuit determines that an abnormality is present;
If the second correlation value is within the first predetermined range or the third correlation value exceeds the second predetermined range, the second current detection circuit determines that the abnormality is present,
If the first correlation value is not less than the predetermined minimum value (Min) and not more than the predetermined maximum value (Max), the first current detection circuit and the second current detection circuit are determined to be normal. Item 10. The power storage device according to Item 9. When the determination means determines that the first current detection circuit and the second current detection circuit are normal,
If the second correlation value exceeds the first predetermined range or the third correlation value exceeds the second predetermined range, the voltage detection circuit determines that an abnormality is present;
11. The voltage detection circuit according to claim 10, wherein if the second correlation value is within the first predetermined range or the third correlation value is within the second predetermined range, the voltage detection circuit determines that the voltage is normal. Power storage device. The determination means, when the second correlation value exceeds a first predetermined range,
If the third correlation value is within the second predetermined range, the first current detection circuit determines that it is abnormal,
If the third correlation value exceeds the second predetermined range, it is determined that the voltage detection circuit is abnormal,
When the second correlation value is within the first predetermined range,
If the third correlation value exceeds the second predetermined range, the second current detection circuit determines that it is abnormal,
10. The power storage device according to claim 9, wherein if the third correlation value is within the second predetermined range, the first current detection circuit, the second current detection circuit, and the voltage detection circuit are determined to be normal. . The first correlation value is an actual difference (S) obtained from an absolute value of a difference between the first charge amount (Q1) and the second charge amount (Q2), or the first charge amount (Q1). ) And the second charge amount (Q2) is an actual measurement ratio (D). The second correlation value is a first actual measurement calculation difference (Sc1) obtained from an absolute value of a difference between the first charge amount (Q1) and the first charge amount calculation value (Q1c), or the first correlation value The power storage device according to claim 9, which is a first actual calculation ratio (Dc1) between a charge amount (Q1) and a first charge amount calculation value (Q1c). The third correlation value is a second actual calculation difference (Sc2) obtained from an absolute value of a difference between the second charge amount (Q2) and the second charge amount calculation value (Q2c), or the second correlation value The power storage device according to claim 9, which is a second actual measurement calculation ratio (Dc2) between the charge amount (Q2) and the second charge amount calculation value (Q2c). At least one of the first power storage element and the second power storage element is provided with a temperature detector electrically connected to the control circuit, or the first power storage element electrically connected to the control circuit And a common temperature detector for the second power storage element,
The determination means determines the first current (I1), the second current (I2), and the storage element voltage (V1) with respect to the temperature (T) according to the temperature (T) detected by the temperature detector. The power storage device according to claim 9, wherein correction is performed from each correlation.

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