JP7115362B2 - Abnormal diagnosis device for power supply - Google Patents

Description

The present invention relates to an abnormality diagnosis device for diagnosing whether or not a power supply device is abnormal.

Among power supply devices mounted on vehicles, there are the following. The power supply device has an assembled battery and an equalization circuit. The assembled battery has a plurality of battery cells. The equalization circuit has a discharge switch for each battery cell, and by turning ON the discharge switch for a battery cell with a large amount of charge, performs equalization processing to equalize the amount of charge of each battery cell.

Some diagnostic devices for diagnosing such an equalization circuit detect whether or not the discharge switch is correctly turned on when discharging should be performed, and if it is turned on, the device is diagnosed as normal. However, if it is not turned ON, there is something that is diagnosed as abnormal. Patent Document 1 is a document showing such a diagnostic device.

JP 2016-152720 A

According to the diagnostic device described above, it is possible to discover an abnormality in the discharge switch. Thereby, it can be diagnosed that the equalization process is abnormal. However, the inventor of the present invention has noticed that an abnormality in the power supply can be caused by factors other than an abnormality in the discharge switch and an abnormality in the equalization process.

Specifically, for example, if the rate of increase in variation in the charge amount of the battery cells is greater than expected, even if the discharge switch is normal and the equalization process itself by discharge is performed normally, the The equalization process cannot sufficiently suppress an increase in variation beyond expectations. As a result, the power supply device loses the cell balance function of maintaining the charge amount of each battery cell in a balanced state. Such a phenomenon in which the speed of variation exceeds expectations is due to, for example, uneven deterioration of each battery cell and differences in the quality of each battery cell at the initial stage of manufacturing the assembled battery. , only some of the battery cells may self-discharge vigorously.

Abnormalities in the power supply due to such factors cannot be found by the diagnostic apparatus described above.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and a main object of the present invention is to enable detection of an abnormality in a power supply due to a factor other than an abnormality in equalization processing.

An abnormality diagnosis device of the present invention diagnoses whether or not a power supply device is abnormal. A power supply device includes an assembled battery having a plurality of battery cells, an equalization circuit for performing equalization processing for equalizing the charge amounts of the plurality of battery cells, and the equalization circuit as necessary during a predetermined processing period. a control device for controlling the equalization circuit so as to perform the equalization process and not perform the equalization process during a predetermined idle period.

The abnormality diagnosis device has a period detection section, an increase detection section, and a diagnosis section. The period detection unit detects at least one of the processing period and the pause period within an evaluation period, which is a period from a predetermined point in time to a predetermined diagnosis timing.

The increase detection unit detects an increase in variation, which is a value obtained by subtracting a predetermined reference value from a variation value indicating variation in the charge amount of the battery cell at the diagnosis timing. The diagnosis unit determines that an evaluation value that satisfies at least one of increasing as the processing period within the evaluation period becomes longer and decreasing as the rest period within the evaluation period becomes longer is a predetermined first evaluation value. The power supply device is diagnosed as abnormal on condition that it is larger than the threshold and the amount of variation increase is larger than a predetermined second threshold.

According to the present invention, the power supply is not diagnosed as abnormal based on the abnormality of the equalization process, but is diagnosed as abnormal based on the fact that the increase in variation is greater than the second threshold. Abnormalities in the power supply due to factors other than process abnormalities can be discovered.

However, if the power supply is diagnosed as abnormal based only on the fact that the increase in variation is greater than the second threshold, the following adverse effects may occur. For example, if the processing period is temporarily extremely short compared to the rest period, even if the power supply is normal, the insufficient processing period will cause an increase in variations in the amount of charge. The processing cannot catch up, and the variation value increases. As a result, the increase in variation exceeds the second threshold, and the power supply is erroneously diagnosed as abnormal.

In this regard, in the present invention, the evaluation value that increases as the processing period within the evaluation period increases or decreases as the idle period increases within the evaluation period is greater than the first threshold, and the power supply is abnormal. I judge. Therefore, as described above, even if the power supply is normal, the increase in variation exceeds the second threshold due to the processing period being temporarily extremely short compared to the rest period, and the power supply becomes abnormal. It is possible to suppress the adverse effects of being misdiagnosed as

Schematic diagram showing the abnormality diagnosis device of the first embodiment Flowchart showing diagnosis by abnormality diagnosis device Graph showing changes in variation values when the processing period is sufficient Graph showing changes in variation values when the processing period is insufficient Graph showing the same transition when the processing period is sufficient in the second embodiment

Next, embodiments of the present invention will be described with reference to the drawings. However, the present invention is not limited to the embodiments, and can be modified as appropriate without departing from the gist of the invention.

[First Embodiment]
FIG. 1 is a schematic diagram showing an abnormality diagnosis device 50 of the first embodiment and its surroundings. The vehicle is equipped with a power supply device 40, an abnormality diagnosis device 50, and the like, in addition to a driving power device. The power plant has an activation switch 75 .

The power supply device 40 has an assembled battery 10 , an equalization circuit 20 and a control section 30 . The assembled battery 10 has a plurality of battery cells 13 . The equalization circuit 20 has a plurality of lead wires 21 , a plurality of connection wires 25 , a plurality of electrical resistors 22 and a plurality of discharge switches 26 . The control unit 30 has a voltage detection unit 31 , a variation detection unit 32 and a switch control unit 33 . The abnormality diagnosis device 50 has a period detection section 51 , an increase detection section 52 and a diagnosis section 53 . The variation detection unit 32, the switch control unit 33, the period detection unit 51, the increment detection unit 52, and the diagnosis unit 53 are each configured by a part of the ECU 64. FIG. An auxiliary battery 65 is connected to the ECU 64 .

First, the power unit will be described in detail. The power unit may be an engine, a motor, or a combination of both (hybrid). When the start switch 75 is turned on, the power plant is started, and when it is turned off, the power plant is stopped. Hereinafter, turning on the start switch 75 is simply referred to as "starting on", and turning off the start switch 75 is simply referred to as "starting off". A period during which the activation switch 75 is ON is referred to as a "activation ON period", and a period during which the activation switch 75 is OFF is referred to as a "activation OFF period".

Next, the power supply device 40 will be described in detail. A plurality of battery cells 13 are connected in series. In the drawing, only three battery cells 13 are schematically shown. Each battery cell 13 is a lithium battery in this embodiment, but may be another battery. A plurality of lead wires 21 are connected between both ends of the assembled battery 10 and between the battery cells 13 . Each connection wiring 25 connects the lead wirings 21 connected to both ends of the same battery cell 13 . This allows the equalization circuit 20 to discharge each battery cell 13 .

The discharge switch 26 is provided on the connection wiring 25 . The discharge switch 26 is a semiconductor switch for switching between ON and OFF of the discharge of each battery cell 13 and is controlled by the switch control section 33 . Specifically, each discharge switch 26 is OFF while no current is input from the switch control section 33 , and is turned ON when power is input from the switch control section 33 . The electrical resistor 22 is provided on the lead wiring 21 . The electrical resistance 22 is a resistance for preventing the discharge current from becoming too large when the battery cell 13 is discharged.

The voltage detection unit 31 detects a terminal voltage Vn (n=1, 2 . . . ) of each battery cell 13 . The voltage detection unit 31 transmits the detected inter-terminal voltage Vn to the variation detection unit 32 .

The variation detection unit 32 calculates the charge amount Qn (n=1, 2 . . . ) of each battery cell 13 based on the inter-terminal voltage Vn detected by the voltage detection unit 31 . Hereinafter, the smallest charge amount Qn will be referred to as "minimum charge amount Qmin", and the largest charge amount Qn will be referred to as "maximum charge amount Qmax". The variation detection unit 32 calculates a variation amount ΔQn (n=1, 2 . Hereinafter, the variation amount ΔQn of the battery cells 13 with the maximum charge amount Qmax is referred to as the variation value Z. As shown in FIG. That is, the variation value Z corresponds to a value obtained by subtracting the minimum charge amount Qmin from the maximum charge amount Qmax. The variation detection unit 32 provides the calculated variation amount ΔQn to the switch control unit 33 and provides the calculated variation value Z to the increase amount detection unit 52 .

The switch control unit 33 turns on each discharge switch 26 as necessary to perform equalization processing for equalizing the charge amount Qn of each battery cell 13 . More specifically, in the equalization process, each battery cell 13 is discharged by the amount of variation ΔQn to equalize the charge amount Qn of each battery cell 13 to the minimum charge amount Qmin.

The switch control unit 33 performs the equalization process during the predetermined processing period T1, and does not perform the equalization process during the predetermined idle period T2. In this embodiment, the processing period T1 is a period during which the equalization process can be performed, and the pause period T2 is a period during which the equalization process cannot be performed. The processing period T1 includes an activation OFF period. On the other hand, the idle period T2 includes the startup ON period.

Specifically, the startup ON period becomes a period during which the equalization process cannot be performed, that is, a pause period T2 for the following reasons. A closed circuit including the assembled battery 10 is formed during the period in which the power of the assembled battery 10 is used or the period in which the assembled battery 10 is charged. Therefore, when the voltage detection unit 31 detects the inter-terminal voltage Vn of each battery cell 13 at this time, the voltage detection unit 31 detects the CCV (closed circuit voltage) of each battery cell 13 . On the other hand, during the period in which the assembled battery 10 is not charged or discharged, a closed circuit including the assembled battery 10 is not formed, that is, an open circuit is formed. Therefore, when the voltage detection unit 31 detects the inter-terminal voltage Vn of each battery cell 13 at this time, the voltage detection unit 31 detects the OCV (open circuit voltage) of each battery cell 13 . In a closed circuit, current flows through the internal resistance of each battery cell 13, so CCV is a value obtained by subtracting the voltage drop due to the current flowing through the internal resistance from OCV.

By the way, the variation detection unit 32 calculates the charge amount Qn (SOC) of each battery cell 13 based on the OCV of each battery cell 13 . Therefore, during the startup ON period when only the CCV of each battery cell 13 can be detected, the variation detector 32 cannot detect the charge amount Qn of each battery cell 13, and therefore cannot detect the variation amount ΔQn of each battery cell 13. Therefore, the startup ON period becomes a period during which the equalization process cannot be performed, that is, a pause period T2.

On the other hand, during the start-off period, the power of the assembled battery 10 is basically not used and the assembled battery 10 is not charged. OCV can be detected. Therefore, the boot-off period is approximately the period during which the equalization process can be performed, that is, the processing period T1.

However, even during the boot-off period, the following predetermined period may be appropriately set to the idle period T2. For example, if there is a period in which the power of the assembled battery 10 is used or a period in which the assembled battery 10 is charged, the OCV of each battery cell 13 cannot be detected during that period even during the startup OFF period. , and the pause period T2.

Further, for example, even in the startup OFF period, when the OCV of each battery cell 13 is within a predetermined range, it is preferable to set the idle period T2 for the following reasons. Generally, when the charge amount Qn of each battery cell 13 increases, the OCV of that battery cell 13 also increases. Therefore, the charge amount Qn can be obtained from the OCV of the battery cell 13 . However, depending on the specification of the battery cell 13, when the OCV of the battery cell 13 is within the predetermined range, the OCV hardly increases even if the charge amount Qn increases. Therefore, the charge amount Qn cannot be obtained from the OCV. Therefore, even when the OCV of each battery cell 13 is within a predetermined range, it is preferable to set the idle period T2 in which the equalization process is not performed.

Further, for example, even during the startup OFF period, if there is a period in which the temperature conditions are not suitable for performing the equalization process, such as when the temperature of the power supply device 40 is too high or too low, that period is also included in the rest period T2. do it. Further, for example, if there is a period in which the state of the voltage detection unit 31 is not suitable for detecting the cell voltage even during the startup OFF period, that period may also be set as the idle period T2. Further, for example, if there is a period during which the auxiliary battery 65 is removed from the ECU 64 in the startup OFF period, the period may be stored and counted as the idle period T2 instead of the processing period T1. . This is because the equalization process cannot be performed during that period because the switch control unit 33 is powered off.

Next, the abnormality diagnosis device 50 will be described in detail. The increase detection unit 52 detects the variation increase ΔZ at a predetermined diagnostic timing when the startup is turned on. The diagnosis timing is the timing immediately before the assembled battery 10 is used due to activation ON. The variation increase amount ΔZ is a value obtained by subtracting the reference value Zo from the variation value Z. As described above, the variation value Z is the variation amount ΔQn of the battery cells 13 with the maximum charge amount Qmax. The reference value Zo is the variation value Z at the previous diagnosis timing.

The period detection unit 51 detects the processing period T1 and the pause period T2 within the evaluation period Te when the activation is turned on. The evaluation period Te is a period from the previous startup ON to the current startup ON (diagnosis timing). Then, the period detection unit 51 calculates an evaluation value E that is a value (T1/T2) obtained by dividing the processing period T1 by the pause period T2.

The diagnosis unit 53 diagnoses whether or not the power supply device 40 is abnormal. The diagnosis unit 53 performs abnormality diagnosis on condition that the evaluation value E is greater than the first threshold value X1. The first threshold value X1 is a minimum required evaluation value E=T1/T2 for the power supply device 40 to exhibit the cell balance function when the power supply device 40 is normal. The cell balance function is a function of maintaining the charge amount Qn of each battery cell 13 in a balanced state.

Further, the diagnosis unit 53 performs abnormality diagnosis on the condition that the most recent parking period Ts, which is the period from the previous activation OFF to the current activation ON (diagnosis timing), is greater than the third threshold value X3. The third threshold value X3 is a waiting period required for the polarization in each battery cell 13 to be eliminated after the assembled battery 10 is used, that is, the voltage detection unit 31 can accurately detect the OCV of the battery cell 13. This is the minimum required open circuit formation period.

Then, in the abnormality diagnosis, the diagnosis unit 53 diagnoses the power supply device 40 as abnormal on the condition that the variation increase amount ΔZ at the current diagnosis timing is larger than the second threshold value X2. The second threshold value X2 is a threshold value for determining that the variation increase amount ΔZ is abnormally large.

The first to third thresholds X1 to X3 may be fixed values or variables. If the thresholds X1 to X3 are variables, they can be set as follows. For example, if the optimum value for the threshold changes depending on the temperature of the power supply device 40, the threshold can be a variable that changes according to the temperature. Specifically, if the optimum value for the threshold increases as the temperature of the power supply device 40 rises, the threshold may be set to a variable that increases as the temperature rises. Also, if the optimum value for the threshold decreases as the temperature of the power supply device 40 rises, the threshold may be a variable that decreases as the temperature rises. Also, for the second threshold value X2, for example, if the optimum value as the threshold value changes according to the evaluation value E, the processing period T1, or the rest period T2, it is preferable to use a variable that changes according to the increase or decrease of them.

The values of these variables can be obtained from maps and formulas. Specifically, for example, when the optimum value as the threshold is a variable that changes with the temperature of the power supply device 40, the threshold is obtained from a map that defines the relationship between the temperature and the correction value of the threshold. Alternatively, the relationship may be obtained by a formula that defines the relationship.

On the other hand, if each of the threshold values X1 to X3 is set to a fixed value, for example, the size of the threshold value can be set according to the temperature at which it is most difficult to be determined to be abnormal within the entire assumed operating temperature range.

FIG. 2 is a flowchart showing diagnosis by the abnormality diagnosis device 50. As shown in FIG. When the startup is turned ON (S101) in a state where the reference value Zo is not set, the evaluation value E=T1/T2 at the timing of the startup ON this time is detected, and whether the evaluation value E is greater than the first threshold value X1. It is determined whether or not (S102). When it is determined that the evaluation value E is smaller than the first threshold value X1 (S102: NO), the diagnosis is terminated assuming that the processing period T1 is insufficient with respect to the rest period T2. Then, the next startup ON starts from S101. On the other hand, when it is determined in S102 that the evaluation value E is greater than the first threshold value X1 (S102: YES), it is determined that the processing period T1 is sufficient for the pause period T2, and the process proceeds to the next step S103.

In step S103, it is determined whether or not the most recent parking period Ts at the timing of the current activation ON is greater than the third threshold value X3 (S103). If it is determined that the most recent parking period Ts is smaller than the third threshold value X3 (S103: NO), it is highly likely that the polarization of the battery cell 13 has not been eliminated and an accurate OCV cannot be obtained, and the diagnosis ends. Then, the next startup ON starts from S101. On the other hand, when it is determined in S103 that the most recent parking period Ts is greater than the third threshold value X3 (S103: YES), the correct OCV of the battery cell 13 can be acquired, and the process proceeds to the next step (S104). In step S104, the variation value Z at the timing of the current startup ON is set as the reference value Zo (S104). After that, it is turned off and waits until it is turned on again (S201).

Then, when the activation is turned ON again (S201), the evaluation value E=T1/T2 at the timing of the activation ON this time is detected, and it is determined whether or not the evaluation value E is greater than the first threshold value X1 (S202). ). When it is determined that the evaluation value E is smaller than the first threshold value X1 (S202: NO), the diagnosis is terminated assuming that the processing period T1 is insufficient with respect to the rest period T2. Then, the next startup ON starts from S101. Therefore, in subsequent S104, the reference value Zo is reset to the latest variation value Z at that time. On the other hand, when it is determined in S202 that the evaluation value E is greater than the first threshold value X1 (S202: YES), it is determined that the processing period T1 is sufficient for the pause period T2, and the process proceeds to the next step S203.

In step S203, it is determined whether or not the most recent parking period Ts at the timing of the current activation ON is greater than the third threshold value X3 (S203). If it is determined that the most recent parking period Ts is smaller than the third threshold value X3 (S203: NO), it is highly likely that an accurate OCV of the battery cell 13 cannot be obtained, and the diagnosis is terminated. Then, the next startup ON starts from S201. On the other hand, when it is determined in S203 that the most recent parking period Ts is greater than the third threshold value X3 (S203: YES), the correct OCV of the battery cell 13 can be obtained, and the process proceeds to the next step (S204).

In step S204, it is determined whether or not the variation increase amount ΔZ at the timing of the current startup ON is greater than the second threshold value X2 (S204). When it is determined that the variation increase ΔZ is smaller than the second threshold value X2 (S204: NO), the variation increase ΔZ is within the normal range, and the power supply device 40 is diagnosed as normal. Then, the next startup ON starts from S201. On the other hand, if the variation increase ΔZ is greater than the second threshold value X2 (S204: YES), the power supply device 40 is diagnosed as abnormal because the variation increase ΔZ is abnormal (S205). Then, use of the assembled battery 10 is prohibited.

According to this embodiment, the following effects are obtained. FIG. 3 is a graph showing transition of the variation value Z when the processing period T1 is sufficient with respect to the idle period T2 (J=T1/T2>X1). When the cell variation speed of the power supply device 40 is normal within the expected range, the increase in the variation value Z during the rest period T2 is sufficiently reduced by the equalization process during the processing period T1, as indicated by the lower polygonal line. can be done. Therefore, the variation increase amount ΔZ does not exceed the second threshold value X2.

On the other hand, when the cell variation speed of the power supply device 40 is more than expected, the increase in the variation value Z during the pause period T2 is sufficiently reduced by the equalization process during the processing period T1, as indicated by the upper polygonal line. I can't. Therefore, the variation increase amount ΔZ exceeds the second threshold value X2. By detecting this, the power supply device 40 can be diagnosed as abnormal.

In the figure, in the case of an abnormality, the variation increase amount ΔZ between a predetermined start-on and the next start-on exceeds the second threshold value X2. , the diagnosing unit 53 can diagnose the power supply device 40 as abnormal even when the variation increase amount ΔZ does not exceed the second threshold value X2. Specifically, the reference value Zo is not reset unless the evaluation value E is smaller than the first threshold value X1. Therefore, if the abnormal state continues without the reference value Zo being reset, the variation increase amount ΔZ accumulates. Therefore, the variation increase amount ΔZ between a predetermined activation ON and the activation ON after several times exceeds the second threshold value X2. By detecting this, the power supply device 40 can be diagnosed as abnormal.

FIG. 4 is a graph showing transition of the variation value Z when the processing period T1 is temporarily insufficient with respect to the rest period T2 (T1/T2<X1). As shown in the lower polygonal line, even when the cell variation speed of the power supply device 40 is normal within the expected range, the processing period T1 is insufficient for the idle period T2. The increment cannot be sufficiently reduced by the equalization processing during the processing period T1. Therefore, even in the normal state, the variation increase amount ΔZ may exceed the second threshold value X2.

In this regard, in this embodiment, when the evaluation value E=T1/T2 is smaller than the first threshold value X1, the diagnosis of whether the power supply device 40 is abnormal is not performed. Therefore, even if the power supply 40 is normal, the increase in variation ΔZ increases due to a temporary extremely short processing period T1, and the power supply 40 is diagnosed as abnormal. can.

Moreover, according to this embodiment, the following adverse effects can also be suppressed. If the evaluation value E is smaller than the first threshold value X1, even if the power supply device 40 is normal, the variation value Z increases and the variation increment ΔZ increases. In this respect, in the present embodiment, when the evaluation value E becomes smaller than the first threshold value X1, and then the evaluation value E=T1/T2 becomes larger than the first threshold value X1, the reference value Zo is set to Update to the latest variation value Z. Therefore, it is possible to prevent the adverse effect of increasing even when the variation increase amount ΔZ is normal.

Further, in the present embodiment, the variation increase amount ΔZ is detected at the timing immediately before the electric power of the assembled battery 10 is used when the start-up is ON. Since the polarization of the battery cells 13 is most resolved at the timing immediately before the power of the assembled battery 10 is used, the variation value Z can be detected with high accuracy. Therefore, the accuracy of abnormality diagnosis is also improved.

Moreover, in this embodiment, it is diagnosed whether the power supply device 40 is abnormal on the condition that the most recent parking period Ts is greater than the third threshold value X3. Therefore, by detecting the OCV of the battery cell 13 in a state in which the polarization of the battery cell 13 is not sufficiently eliminated, it is possible to suppress the adverse effect of lowering the accuracy of abnormality diagnosis.

Further, in this embodiment, the equalization process is generally performed during the startup OFF period from startup OFF to ON, and the equalization process is suspended during the startup ON period from startup ON to OFF. can do. Further, in the present embodiment, when the power supply device 40 is diagnosed as abnormal, continued use of the power supply device 40 is prohibited, thereby preventing deterioration of the power supply device 40 .

[Second embodiment]
Next, a second embodiment will be described. In the following embodiments, members that are the same as or correspond to those in the previous embodiments are denoted by the same reference numerals. The present embodiment will be described based on the first embodiment, focusing on points that differ from this.

In the present embodiment, contrary to the first embodiment, the processing period T1 is approximately the activation ON period, and the rest period T2 is approximately the activation OFF period. Such a configuration can be implemented, for example, by obtaining the internal resistance of each battery cell 13 in advance and calculating the OCV from the internal resistance, the current flowing through it, and the CCV. As for the boot-off period, although the equalization process can be performed in this embodiment as well, it is set to the pause period T2 here.

FIG. 5 is a graph showing changes in the variation value Z over time when the processing period T1 is sufficient for the rest period T2 (T1/T2>X1) in this embodiment. According to this embodiment, the abnormality diagnosis is performed for the power supply device 40 that has specifications such that the equalization process is performed during the activation ON period from activation ON to OFF, and the equalization process is suspended during the activation OFF period from activation OFF to ON. can be done.

[Other embodiments]
For example, the above embodiment can be implemented by changing as follows. Instead of setting the amount of variation ΔQn of each battery cell 13 to the amount obtained by subtracting the minimum charge amount Qmin from the charge amount Qn of the battery cell 13, It may be obtained by subtracting the average value of the charge amount Qn. Furthermore, in that case, the equalization process may be a process of discharging the battery cells 13 with the positive variation ΔQn and charging the battery cells 13 with the negative variation ΔQn.

Further, instead of setting the variation value Z to a value obtained by subtracting the minimum charge amount Qmin from the maximum charge amount Qmax, a value obtained by dividing the maximum charge amount Qmax by the minimum charge amount Qmin may be used.

Also, instead of setting the evaluation period Te to the period from the previous activation ON to the current activation ON, it is set to the period from the activation ON several times before to the current activation ON. It may be a period from before the time to the current activation ON.

Also, the evaluation value E may be set to the processing period T1 instead of the value obtained by dividing the processing period T1 by the idle period T2. In that case, the determination (S102, S202) as to whether or not the processing period T1 is sufficient with respect to the pause period T2 is simply a determination as to whether or not the processing period T1 has exceeded the first threshold value X1. Also, the evaluation value E may be the reciprocal of the pause period T2 (1/T2). In that case, the determination (S102, S202) of whether or not the processing period T1 was sufficient with respect to the rest period T2 is simply based on whether the rest period T2 exceeded the reciprocal (1/X1) of the first threshold value X1. will be judged.

Alternatively, the evaluation value E may be the processing period T1 minus the idle period T2 (E=T1-T2). Also, the evaluation value E may be another function of T1 and T2 (eg, E=8×T1−T2). Alternatively, the evaluation value E may be a function that increases as the processing period T1 within the evaluation period Te increases and decreases as the pause period T2 within the evaluation period Te increases. Also, the evaluation value E is set as a function that satisfies at least one of the following: the larger the processing period T1 within the evaluation period Te, the larger the evaluation value E, and the larger the pause period T2 within the evaluation period Te, the smaller the evaluation value E. good too.

Further, instead of setting the diagnostic timing to the timing just before the electric power of the assembled battery 10 is used when the activation is ON, it is set to the timing when the most recent parking period Ts in the activation OFF period becomes larger than the third threshold value X3. may

Further, when it is determined in S202 that the evaluation value E is smaller than the first threshold value X1 (S202: NO), instead of returning to S101, the process may return to S201. Further, when it is determined in S203 that the most recent parking period Ts is smaller than the third threshold value X3 (S203: NO), or when it is determined in S204 that the variation increase amount ΔZ is smaller than the second threshold value X2 (S204). , instead of returning to S201, the process may return to S101.

Further, when the abnormality diagnosis device 50 determines YES in S204, instead of determining that the power supply device 40 is abnormal (S205), the abnormality diagnosis device 50 increases the abnormality count by one, and restarts from S101 or S201 at the next activation ON. You may do so. Then, only when the abnormality count reaches a predetermined number of times or more, the process may proceed to S205 and the power supply device 40 may be diagnosed as abnormal. In this case, the diagnosis can be made more cautiously.

Alternatively, S101 to S104 may be omitted, and the reference value Zo may be a fixed value or a variable variable depending on temperature or the like. Further, S103 or S203, that is, the determination of whether or not the most recent parking period Ts at the timing of the activation ON this time is greater than the third threshold value X3 may be eliminated. Also in the second embodiment, as in the first embodiment, only the period during which the equalization process cannot be performed may be set as the idle period T2. Then, most of both the activation ON period and the activation OFF period may be set to the processing period T1.

DESCRIPTION OF SYMBOLS 10... Assembled battery, 13... Battery cell, 20... Equalization circuit, 30... Control part, 40... Power supply device, 50... Abnormal diagnosis device, 51... Period detection part, 52... Increase detection part, 53... Diagnosis part, E... evaluation value, T1... processing period, T2... pause period, Te... evaluation period, X1... first threshold value, X2... second threshold value, Z... variation value, Zo... reference value, ?Z... increase in variation.

Claims (10)

An assembled battery (10) having a plurality of battery cells (13), an equalization circuit (20) for performing equalization processing for equalizing the charge amounts of the plurality of battery cells, and a predetermined processing period (T1) and a control unit (30) for controlling the equalization circuit so that the equalization process is performed as necessary in and the equalization process is not performed during a predetermined rest period (T2). (40) in an abnormality diagnosis device (50) for diagnosing whether or not there is an abnormality,
a period detection unit (51) for detecting at least one of the processing period and the rest period within an evaluation period (Te), which is a period from a predetermined point in time to a predetermined diagnosis timing;
An increase detection unit (52) for detecting a variation increase (ΔZ), which is a value obtained by subtracting a predetermined reference value (Zo) from a variation value (Z) indicating variation in the charge amount of the battery cell at the diagnostic timing. When,
An evaluation value (E) that satisfies at least one of increasing the processing period within the evaluation period and decreasing the pause period within the evaluation period is a predetermined first threshold value ( X1) and the increase in variation is greater than a predetermined second threshold value (X2), a diagnosis unit (53) diagnosing the power supply device as abnormal;
Abnormal diagnosis device having After the diagnosis unit determines that the evaluation value is smaller than the first threshold, the reference value is updated to the latest variation value when the evaluation value becomes larger than the first threshold. 2. The abnormality diagnosis device according to claim 1, wherein the next diagnosis as to whether or not the power supply device is abnormal is performed after that. The power supply device is mounted on a vehicle,
The processing period includes a start-off period during which the start switch (75) of the power plant for running the vehicle is turned off, and the rest period is a start-up period during which the start switch is turned on. 3. The abnormality diagnosis device according to claim 1, including an ON period. The power supply device is mounted on a vehicle,
The processing period includes an activation ON period during which the activation switch (75) of the power unit for running the vehicle is ON, and the idle period is activation during the activation switch is OFF. 3. The abnormality diagnosis device according to claim 1, including an OFF period. The power supply device is mounted on a vehicle,
5. The diagnostic timing according to any one of claims 1 to 4, wherein the diagnosis timing is a timing immediately before an activation switch (75) of a power plant for running the vehicle is turned on and electric power of the assembled battery is used. Abnormal diagnosis device as described. The diagnosing unit detects the power supply on the condition that a most recent parking period (Ts), which is a period from when the start switch is finally turned off to the diagnosis timing, is longer than a predetermined third threshold value (X3). 6. The abnormality diagnosis device according to claim 5, which diagnoses whether or not the device is abnormal. 7. The abnormality diagnosis device according to claim 5, wherein said evaluation period is a period from when said start switch was turned on last time to when said start switch is turned on this time. The abnormality diagnosis device according to any one of claims 1 to 7, wherein said evaluation value is a value obtained by dividing said processing period by said idle period. The abnormality diagnosis device according to any one of claims 1 to 8, wherein at least one of said first threshold and said second threshold is a variable that changes according to the temperature of said power supply device. The diagnostic unit determines that the power supply device is abnormal on condition that the evaluation value is greater than the first threshold value and the variation increase amount is greater than the second threshold value at the diagnostic timing of a predetermined number of times or more. The abnormality diagnosis device according to any one of claims 1 to 9, which diagnoses.

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