JP2021135106A - Determination apparatus and determination method - Google Patents

Abstract

To provide a determination apparatus and a determination method that are capable of improving the determination accuracy when determining a thermistor in which an abnormality has occurred of a plurality of thermistors.SOLUTION: A determination apparatus comprises a selection unit, a decision unit, and a determination unit. The selection unit selects a predetermined normal thermistor from among a plurality of thermistors. The decision unit decides a threshold value for determining an abnormal thermistor of the plurality of thermistors according to a temperature detected by the predetermined thermistor selected by the selection unit. The determination unit determines a thermistor in which an abnormality has occurred of the plurality of thermistors, using the threshold value decided by the decision unit.SELECTED DRAWING: Figure 1A

Description

The present invention relates to a determination device and a determination method.

Conventionally, there is known a technique of measuring the temperature of an object with a plurality of thermistors provided on the object (see, for example, Patent Document 1). Further, in the prior art, the thermistor in which an abnormality has occurred is determined among a plurality of thermistors.

Japanese Unexamined Patent Publication No. 2012-122930

However, there is room for further improvement in the prior art in that the determination accuracy when determining the thermistor in which an abnormality has occurred among a plurality of thermistors is improved.

The present invention has been made in view of the above, and an object of the present invention is to provide a determination device and a determination method capable of improving the determination accuracy when determining a thermistor in which an abnormality has occurred among a plurality of thermistors. And.

In order to solve the above problems and achieve the object, the present invention includes a selection unit, a determination unit, and a determination unit in the determination device. The selection unit selects a normal predetermined thermistor from a plurality of thermistors. The determination unit determines a threshold value for determining an abnormal thermistor from the plurality of thermistors according to the temperature detected by the predetermined thermistor selected by the selection unit. The determination unit determines the thermistor in which an abnormality has occurred among the plurality of thermistors by using the threshold value determined by the determination unit.

According to the present invention, it is possible to improve the determination accuracy when determining a thermistor in which an abnormality has occurred among a plurality of thermistors.

FIG. 1A is a diagram illustrating an outline of a determination method of the determination device according to the first embodiment. FIG. 1B is a graph of characteristics showing the relationship between the output voltage of the thermistor and the temperature. FIG. 1C is a graph showing a voltage difference corresponding to a predetermined temperature difference and the like. FIG. 2 is a block diagram showing a configuration of a battery system including a determination device according to the first embodiment. FIG. 3 is a diagram showing an example of threshold information. FIG. 4 is a diagram showing an example of characteristic information. FIG. 5 is a flowchart showing a processing procedure executed by the determination device according to the first embodiment. FIG. 6 is a block diagram showing a configuration of a battery system including the determination device according to the second embodiment. FIG. 7 is a flowchart showing a processing procedure executed by the determination device according to the second embodiment. FIG. 8 is a block diagram showing a configuration of a battery system including a determination device according to a third embodiment. FIG. 9 is a flowchart showing a processing procedure executed by the determination device according to the third embodiment.

Hereinafter, embodiments of the determination device and the determination method disclosed in the present application will be described in detail with reference to the accompanying drawings. The present invention is not limited to the embodiments shown below.

(First Embodiment)
In the following, the determination device determines the temperature of a lithium-ion secondary battery (LIB: Lithium-Ion rechargeable battery, hereinafter referred to as LIB) mounted on a vehicle such as an HEV (Hybrid Electric Vehicle) or EV (Electric Vehicle). An example of determining whether or not an abnormality has occurred in a plurality of thermistas to be detected will be described. The object of temperature detection by the thermistor is not limited to the LIB, and may be, for example, other parts such as a relay or a substrate mounted on the vehicle, or any part other than the parts mounted on the vehicle. It may be.

First, the outline of the determination method of the determination device according to the first embodiment will be described with reference to FIGS. 1A to 1C. FIG. 1A is a diagram illustrating an outline of a determination method of the determination device according to the first embodiment. Note that FIG. 1A is also a block diagram showing a configuration example of a vehicle battery system including a determination device.

As shown in FIG. 1A, the battery system 1 includes a battery pack 10, a generator 11, a starter 12, a lead battery 13, and a host ECU (Electronic Control Unit) 100. The battery pack 10 includes a LIB 14, a thermistor 15, a first switch 16, a second switch 17, and a determination device 20.

As described above, the battery system 1 is a dual power supply system including two batteries, a lead battery 13 and a LIB 14. The battery system 1 is not limited to the dual power supply system in which the batteries are duplicated, and the number of batteries may be one or three or more.

The generator 11 is a device that generates electric power by using the rotation of an engine as a power source. In addition, when the vehicle is decelerating, regenerative power is generated by the regenerative brake. The generator 11 is also called an alternator or a generator.

Further, the generator 11 may generate electric power in response to an instruction from, for example, the upper ECU 100. Then, for example, the generated electric power is supplied to the lead battery 13 and the LIB 14 to charge the lead battery 13 and the LIB 14.

The starter 12 is, for example, a starting device including an electric motor to start an engine. In the example shown in FIG. 1A, the battery system 1 is configured to include the starter 12 and the generator 11, but for example, an ISG (Integrated Starter Generator) may be provided instead of the starter 12 and the generator 11. ..

The lead battery 13 is a secondary battery using lead as an electrode. The lead battery 13 is, for example, a main power source for electrical equipment mounted on a vehicle.

The LIB 14 of the battery pack 10 is a secondary battery that charges or discharges, and serves as an auxiliary power source for, for example, a lead battery 13. As the LIB 14, an iron-based LIB can be used, but the LIB 14 is not limited to this. LIB 14 is an example of an object.

The thermistor 15 is provided on the LIB 14 and measures the temperature of the LIB 14. A plurality (for example, two) thermistors 15 are provided in the LIB 14 for redundancy. The thermistor 15 outputs a voltage corresponding to the measured temperature of the LIB 14 to the determination device 20.

In the following, the two thermistors 15 may be described as "first thermistor 15a" and "second thermistor 15b", but when these are described without particular distinction, they are described as "thermistor 15". do. Further, in FIG. 1A, two thermistors 15 are shown, but these are merely examples and are not limited, and may be three or more.

The first switch 16 and the second switch 17 are switches (relays) that control short circuits and open circuits. The first switch 16 is connected between the lead battery 13 and the generator 11 (or starter 12). The second switch 17 is connected between the LIB 14 and the generator 11 (or starter 12). The opening and closing of the first switch 16 and the second switch 17 is controlled by the higher-level ECU 100 described above.

The higher-level ECU 100 is a higher-level ECU of the battery pack 10, acquires a vehicle condition or the like at any time, and controls the battery pack 10 according to the vehicle condition or the like. For example, the upper ECU 100 acquires information on the vehicle status, the status of the LIB 14, information on the status of the lead battery 13, and the like. The information regarding the state of the LIB 14 includes, for example, information on the state of charge (SOC) of the LIB 14. The above-mentioned SOC is, for example, the charge rate (charge amount) of LIB14.

Then, the upper ECU 100 opens and closes the first switch 16 and the second switch 17 based on the vehicle condition, the state of the LIB 14 (for example, SOC), the state of the lead battery 13, and charges and discharges the lead battery 13 and the LIB 14. Control. Further, the upper ECU 100 controls the operation of various electric devices such as a generator 11, a starter 12, and an auxiliary machine (not shown) according to a vehicle condition or the like.

The determination device 20 determines the thermistor 15 in which an abnormality has occurred among the plurality of thermistors 15. For example, the determination device 20 determines that an abnormality has occurred in the thermistor 15 when there is a voltage difference corresponding to a predetermined temperature difference in the voltages output from the plurality of thermistors 15. The predetermined temperature difference is set to, for example, 30 ° C., but this is an example and is not limited.

By the way, the voltage difference corresponding to the above-mentioned predetermined temperature difference can be a threshold value when the determination device 20 determines an abnormality, but the above-mentioned voltage difference is measured by the characteristic showing the relationship between the output voltage of the thermistor 15 and the temperature. It changes according to the temperature.

The change in the voltage difference will be described with reference to FIG. 1B. FIG. 1B is a graph of characteristics showing the relationship between the output voltage of the thermistor 15 and the temperature.

As shown in FIG. 1B, the output voltage of the thermistor 15 changes according to the temperature, but the relationship between the temperature and the output voltage is not proportional. For example, when the temperature to be measured is in the high temperature region, the change in the output voltage with respect to the change in temperature becomes relatively gradual. On the other hand, for example, when the temperature to be measured is in the intermediate region between the high temperature region and the low temperature region, the change in the output voltage with respect to the change in temperature becomes relatively steep.

Therefore, for example, the voltage difference B1 corresponding to the predetermined temperature difference A1 when the temperature to be measured is in the intermediate region is different from the voltage difference B2 corresponding to the predetermined temperature difference A2 when the temperature to be measured is in the high temperature region. Differently, the voltage difference is larger than B2 (B1> B2). The predetermined temperature difference A1 and the predetermined temperature difference A2 in FIG. 1B have the same temperature difference.

As described above, in the thermistor 15, the voltage differences B1 and B2 corresponding to the predetermined temperature difference change according to the temperature to be measured. FIG. 1C is a graph showing a voltage difference corresponding to such a predetermined temperature difference.

Here, the threshold value when the determination device 20 determines an abnormality is preferably set along the voltage difference corresponding to the predetermined temperature difference, as shown by the alternate long and short dash line in FIG. 1C, in other words, the temperature to be measured. It is preferable that it is set variably according to the situation. However, in the prior art, the threshold cannot be set as described above.

For example, when a voltage difference corresponding to a predetermined temperature difference occurs between the first thermistor 15a and the second thermistor 15b, it can be determined that an abnormality has occurred in the thermistor 15, but the first and second thermistors 15a, It is difficult to determine which of the 15b is abnormal and which is normal. Therefore, in the prior art, it is difficult to determine which of the temperatures measured by the first and second thermistors 15a and 15b is the correct temperature, and the threshold value is variably set according to the measured temperature. I couldn't. Therefore, in the prior art, the threshold value is set to a constant value of the maximum voltage difference Da in the entire temperature range.

However, when the threshold value is set as in the conventional technique, the voltage difference corresponding to the actual predetermined temperature difference and the threshold value set in the conventional technique greatly deviate from each other depending on the temperature to be measured. Therefore, in the prior art, if the voltage difference between the thermistors 15 is equal to or greater than the voltage difference corresponding to the predetermined temperature difference but does not exceed the threshold value, it can be determined that an abnormality has occurred. However, there is a risk that the judgment accuracy will be reduced.

Therefore, in the determination device 20 according to the present embodiment, the determination accuracy when determining the thermistor 15 in which an abnormality has occurred among the plurality of thermistors 15 is improved.

More specifically with reference to FIG. 1A, the determination device 20 first acquires the temperatures detected by the plurality of thermistors 15 (step S1). Next, the determination device 20 selects a normal predetermined thermistor from the plurality of thermistors 15 (step S2). That is, in the present embodiment, the process of selecting a normal predetermined thermistor is executed before the process of determining the occurrence of an abnormality. The details of the process of selecting a normal predetermined thermistor will be described later.

Next, the determination device 20 determines the threshold value according to the temperature detected by the predetermined thermistor (step S3). Specifically, the determination device 20 determines the threshold value according to the accurate temperature detected by a normal predetermined thermistor. In the example shown in FIG. 1C, when the temperature C1 is detected by the predetermined thermistor, the determination device 20 determines the threshold value D1. As described above, the determination device 20 according to the present embodiment can set the threshold value variably according to the accurate temperature measured by the predetermined thermistor.

Continuing the description of FIG. 1A, the determination device 20 determines the thermistor 15 in which an abnormality has occurred among the plurality of thermistors 15 using the threshold value (step S4).

In the present embodiment, the threshold value is variably set according to the temperature and is set along the voltage difference corresponding to the predetermined temperature difference. Therefore, in the determination device 20, the voltage difference between the thermistors 15 is predetermined. When the voltage difference corresponding to the temperature difference exceeds the threshold value, it can be accurately determined that the thermistor 15 has an abnormality. That is, in the determination device 20 according to the present embodiment, it is possible to improve the determination accuracy when determining the thermistor 15 in which an abnormality has occurred among the plurality of thermistors 15.

Next, with reference to FIG. 2, the configuration of the battery system 1 including the determination device 20 according to the first embodiment will be described in detail. FIG. 2 is a block diagram showing a configuration of a battery system 1 including a determination device 20 according to the first embodiment. Note that, in FIG. 2, only the components necessary for explaining the features of the present embodiment are represented by functional blocks, and the description of general components is omitted.

In other words, each component shown in FIG. 2 is a functional concept and does not necessarily have to be physically configured as shown in the figure. For example, the specific form of distribution / integration of each functional block is not limited to the one shown in the figure, and all or part of the functional blocks are functionally or physically distributed in arbitrary units according to various loads and usage conditions. -It is possible to integrate and configure.

As shown in FIG. 2, the battery system 1 includes the above-mentioned LIB 14, a determination device 20, a higher-level ECU 100, a current sensor 61, a voltage sensor 62, a first thermistor 15a, a second thermistor 15b, and various types of electricity. The device 70 and the first and second switches 16 and 17 are provided.

In FIG. 2, for simplification of the illustration, the above-mentioned generator 11 and starter 12, for example, auxiliary machines (loads) mounted on the vehicle such as a navigation device, audio, and air conditioner are used as various electric devices 70. Shown in blocks. Further, in FIG. 2, the first switch 16 and the second switch 17 are shown by one block.

The current sensor 61 is a sensor that measures the charge / discharge current of the LIB 14. The voltage sensor 62 is a sensor that measures the battery voltage of the LIB 14. The first thermistor 15a and the second thermistor 15b measure the temperature (battery temperature) of the LIB 14. The current sensor 61, the voltage sensor 62, and the first and second thermistors 15a and 15b output signals indicating the measurement results to the determination device 20, respectively.

The determination device 20 includes a control unit 30 and a storage unit 40. The control unit 30 includes an acquisition unit 31, a detection unit 32, a selection unit 33, a determination unit 34, and a determination unit 35.

The control unit 30 includes, for example, a computer having a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an HDD (Hard Disk Drive), an input / output port, and various circuits.

The CPU of the computer functions as the acquisition unit 31, the detection unit 32, the selection unit 33, the determination unit 34, and the determination unit 35 of the control unit 30, for example, by reading and executing the program stored in the ROM.

Further, at least a part or all of the acquisition unit 31, the detection unit 32, the selection unit 33, the determination unit 34, and the determination unit 35 of the control unit 30 are ASIC (Application Specific Integrated Circuit), FPGA (Field Programmable Gate Array), or the like. It can also be configured with the hardware of.

Further, the storage unit 40 is a storage device such as a data flash, a non-volatile memory, or a register. The storage unit 40 stores the threshold value information 41 and the characteristic information 42.

The threshold value information 41 is threshold value information that can determine that an abnormality has occurred in the thermistor 15. Here, the threshold value information 41 will be specifically described with reference to FIG. FIG. 3 is a diagram showing an example of the threshold information 41.

As shown in FIG. 3, the threshold information 41 includes information on a graph showing a threshold set according to the temperature detected by a predetermined thermistor. Such a threshold is the voltage difference between the thermistors 15. Specifically, as the threshold value, a value corresponding to a voltage difference corresponding to a predetermined temperature difference (for example, 30 ° C.) with respect to the voltage of a predetermined thermistor selected as a normal thermistor 15 from a plurality of thermistors 15 is set. .. The threshold information 41 is set in advance based on, for example, a characteristic (see FIG. 1B) indicating the relationship between the output voltage of the thermistor 15 and the temperature.

Therefore, for example, when the first thermistor 15a is selected as the predetermined thermistor, when the voltage difference between the second thermistor 15b and the first thermistor 15a becomes equal to or larger than the threshold value, the second thermistor 15b will be the first thermistor 15a. It can be determined that an abnormality has occurred in the second thermistor 15b because the temperature deviating from the detected temperature (in other words, the accurate temperature) in the above is detected by a predetermined temperature or more.

Returning to the description of FIG. 2, the characteristic information 42 is information indicating the characteristics related to the temperature of the object to be detected by the temperature of the thermistor 15. In the example of FIG. 2, the object is LIB14. Therefore, the characteristic information 42 includes information indicating the temperature-related characteristics of the LIB 14. Here, the characteristic information 42 will be specifically described with reference to FIG. FIG. 4 is a diagram showing an example of the characteristic information 42.

As shown in FIG. 4, the characteristic information 42 includes information regarding the characteristics of the battery temperature when the LIB 14 is charged and discharged. For example, the characteristic information 42 includes information on the characteristics of the battery temperature that can occur when a predetermined charge / discharge time elapses in a state of being charged / discharged with a predetermined charge / discharge current in the LIB 14.

Therefore, as will be described later, the selection unit 33 is based on the actual charge / discharge information of the LIB 14 (specifically, historical information regarding the charge / discharge current (for example, average charge / discharge current) and charge / discharge time) and the characteristic information 42. It becomes possible to estimate the battery temperature of the LIB 14.

In the example shown in FIG. 4, the characteristics of the battery temperature that fluctuate according to the charge / discharge current and the charge / discharge time are shown, but the present invention is not limited to this, and various factors that affect the battery temperature such as the outside air temperature are considered. The characteristic of the battery temperature may be included in the characteristic information 42.

Returning to the description of FIG. 2, the acquisition unit 31 of the control unit 30 acquires the characteristic information 42. For example, the acquisition unit 31 accesses the storage unit 40 to acquire the characteristic information 42, and outputs the acquired characteristic information 42 to the selection unit 33.

The detection unit 32 detects the current (charge / discharge current) of the LIB 14 based on the signal input from the current sensor 61. Further, the detection unit 32 detects the voltage of the LIB 14 based on the signal input from the voltage sensor 62.

The detection unit 32 is based on the signals input from the first thermistor 15a and the second thermistor 15b, and the temperature detected by the thermistors 15a and 15b (in other words, when no abnormality has occurred in the thermistors 15a and 15b). LIB14 temperature) is detected.

To be precise, the detection unit 32 receives a signal from the first thermistor 15a indicating an output voltage corresponding to the temperature detected by the first thermistor 15a. The detection unit 32 detects the detection temperature in the first thermistor 15a based on the output voltage. Similarly, the detection unit 32 receives a signal from the second thermistor 15b indicating an output voltage corresponding to the detection temperature of the second thermistor 15b. The detection unit 32 detects the temperature detected by the second thermistor 15b based on the output voltage.

The detection unit 32 outputs the detected current and voltage of the LIB 14, the output voltage of the first and second thermistors 15a and 15b, and the detection temperature to the selection unit 33, the determination unit 34, the determination unit 35, and the like.

The selection unit 33 selects a normal predetermined thermistor from the plurality of thermistors 15. For example, the selection unit 33 uses a predetermined thermistor based on the characteristic information 42 acquired by the acquisition unit 31 and the detection temperatures detected by the plurality of thermistors 15 (here, the first and second thermistors 15a and 15b), respectively. Select. As a result, the selection unit 33 can accurately select a normal predetermined thermistor.

Specifically, the selection unit 33 first estimates the battery temperature of the LIB 14. For example, the selection unit 33 measures the charge / discharge current (for example, average charge / discharge current) and charge / discharge time of the LIB 14 and generates charge / discharge information (history information) of the LIB 14. Then, the selection unit 33 estimates the battery temperature of the LIB 14 based on the charge / discharge information of the LIB 14 and the information indicating the temperature-related characteristics of the LIB 14 included in the characteristic information 42 (see FIG. 4). In this way, the selection unit 33 estimates the battery temperature of the LIB 14 without using the signals from the first and second thermistors 15a and 15b.

Then, the selection unit 33 selects the thermistor 15 whose detection temperature is close to the estimated battery temperature among the first and second thermistors 15a and 15b as the predetermined thermistor. As an example, in the selection unit 33, the estimated battery temperature of the LIB 14 is "40 ° C", the detection temperature of the first thermistor 15a is "40 ° C", and the detection temperature of the second thermistor 15b is "30 ° C". If so, the first thermistor 15a is selected as the predetermined thermistor. The selection unit 33 outputs information indicating the selection result to the determination unit 34.

In this way, the selection unit 33 estimates the battery temperature from the characteristics of the LIB 14 without using the signals from the first and second thermistors 15a and 15b, and selects a predetermined thermistor based on the estimated battery temperature. I did. As a result, in the present embodiment, a normal predetermined thermistor can be accurately selected regardless of the presence or absence of abnormalities in the first and second thermistors 15a and 15b.

The determination unit 34 determines a threshold value for determining the abnormal thermistor 15 according to the detection temperature detected by the predetermined thermistor. For example, the determination unit 34 accesses the storage unit 40 and reads out the threshold value information 41 (see FIG. 3). Then, the determination unit 34 determines (sets) the threshold value based on the detection temperature in the predetermined thermistor and the threshold value information 41.

This makes it possible to variably set the threshold value according to the accurate temperature detected by a normal predetermined thermistor in the present embodiment.

The determination unit 35 determines the thermistor 15 in which an abnormality has occurred among the plurality of thermistors 15. For example, the thermistor 15 in which the abnormality has occurred is determined using the threshold value determined by the determination unit 34.

Specifically, the determination unit 35 calculates the voltage difference based on the output voltage of the target thermistor, which is a thermistor 15 other than the predetermined thermistor and is the target of determination, and the output voltage of the predetermined thermistor. Then, when the voltage difference (more accurately, the absolute value of the voltage difference) is equal to or greater than the threshold value, the determination unit 35 determines that an abnormality has occurred in the target thermistor.

That is, since the target thermistor is in a state of detecting a temperature deviating from the detection temperature (in other words, an accurate temperature) of the predetermined thermistor by a predetermined temperature or more, the determination unit 35 has an abnormality in the target thermistor. Judge that it has occurred. When the voltage difference is less than the threshold value, the determination unit 35 determines that no abnormality has occurred in the target thermistor.

As described above, in the present embodiment, by using the threshold value variably set according to the accurate temperature detected by the normal predetermined thermistor, the thermistor 15 may be in what temperature range. However, it is possible to accurately determine that an abnormality has occurred in the thermistor 15.

Next, the processing procedure executed by the determination device 20 according to the first embodiment will be described with reference to FIG. FIG. 5 is a flowchart showing a processing procedure executed by the determination device 20 according to the first embodiment.

As shown in FIG. 5, the control unit 30 of the determination device 20 first acquires the characteristic information 42 regarding the temperature of the LIB 14 (step S10). Next, the control unit 30 detects the charge / discharge current of the LIB 14 and the like (step S11).

The control unit 30 estimates the battery temperature of the LIB 14 based on the characteristic information 42 and the charge / discharge current and the charge / discharge time of the LIB 14 (step S12). Next, the control unit 30 acquires the temperature detected by the first and second thermistors 15a and 15b (step S13).

The control unit 30 selects a normal predetermined thermistor based on the estimated battery temperature of the LIB 14 and the detected temperatures of the first and second thermistors 15a and 15b (step S14). Subsequently, the control unit 30 determines the threshold value according to the detection temperature detected by the predetermined thermistor (step S15).

Next, the control unit 30 determines whether or not the voltage difference between the predetermined thermistor and the target thermistor is equal to or greater than the threshold value (step S16). When the control unit 30 determines that the voltage difference is equal to or greater than the threshold value (step S16, Yes), the control unit 30 determines that an abnormality has occurred in the target thermistor (step S17). On the other hand, when it is determined that the voltage difference is not equal to or greater than the threshold value (steps S16, No), the control unit 30 ends the process as it is.

As described above, the determination device 20 according to the first embodiment includes a selection unit 33, a determination unit 34, and a determination unit 35. The selection unit 33 selects a normal predetermined thermistor from the plurality of thermistors 15. The determination unit 34 determines a threshold value for determining an abnormal thermistor 15 from a plurality of thermistors 15 according to the temperature detected by a predetermined thermistor selected by the selection unit 33. The determination unit 35 determines the thermistor 15 in which an abnormality has occurred among the plurality of thermistors 15 by using the threshold value determined by the determination unit 34. As a result, it is possible to improve the determination accuracy when determining the thermistor 15 in which an abnormality has occurred among the plurality of thermistors 15.

In the first embodiment described above, since the object of temperature detection by the first and second thermistors 15a and 15b is the LIB 14, the characteristic information 42 includes information indicating the temperature characteristics of the LIB 14. , Not limited to this. That is, for example, when the object of temperature detection by the first and second thermistors 15a and 15b is a relay such as the first switch 16 (or the second switch 17), the characteristic information 42 contains the characteristics related to the temperature of the relay. The information to be shown will be included.

(Second Embodiment)
Next, the determination device 20 according to the second embodiment will be described. In the determination device 20 according to the second embodiment, when selecting a predetermined thermistor from a plurality of thermistors 15, information indicating the temperature of another object in the vicinity of the object for temperature detection of the thermistor 15 is used. I did.

Hereinafter, the determination device 20 according to the second embodiment will be described with reference to FIG. FIG. 6 is a block diagram showing the configuration of the battery system 1 including the determination device 20 according to the second embodiment. In the following, the same reference numerals will be given to the configurations common to those of the first embodiment, and the description thereof will be omitted.

As shown in FIG. 6, the battery system 1 includes a temperature sensor 18 for other objects. Further, in the second embodiment, the characteristic information 42 of the first embodiment is removed in the storage unit 40.

Further, the first and second thermistors 15a and 15b according to the second embodiment measure the temperature of a relay such as the first switch 16 (or the second switch 17). The relay is an example of an object.

Such a relay is mounted on a substrate (not shown). The substrate may be near the relay, in other words, within a predetermined range of the relay, and is an example of another object. The predetermined range is set to a temperature similar to, for example, the temperature of the relay, but the temperature is not limited to this and may be set to any range.

The temperature sensor 18 for other objects described above is provided on the substrate and measures the temperature of the substrate. The temperature sensor 18 for other objects outputs the measured information indicating the temperature of the substrate (hereinafter, may be referred to as “other object temperature information”) to the determination device 20. As the temperature sensor 18 for other objects, a thermistor or a thermocouple can be used, but the temperature sensor 18 is not limited to this.

In the determination device 20, the acquisition unit 31 of the control unit 30 acquires the temperature information of the other object output from the temperature sensor 18 for the other object. The acquisition unit 31 outputs the acquired temperature information of the other object to the selection unit 33.

The selection unit 33 is a predetermined thermistor based on the temperature information of other objects acquired by the acquisition unit 31 and the detection temperatures detected by the plurality of thermistors 15 (here, the first and second thermistors 15a and 15b), respectively. Select.

Specifically, the selection unit 33 selects, among the first and second thermistors 15a and 15b, the thermistor 15 whose detection temperature is close to the temperature of the substrate included in the temperature information of other objects as a predetermined thermistor. do.

As an example, when the temperature of the substrate of the selection unit 33 is "45 ° C", the detection temperature of the first thermistor 15a is "40 ° C", and the detection temperature of the second thermistor 15b is "20 ° C", The first thermistor 15a is selected as the predetermined thermistor.

As described above, the selection unit 33 does not use the signals from the first and second thermistors 15a and 15b, and has a temperature similar to that of the object for temperature detection of the first and second thermistors 15a and 15b. A predetermined thermistor was selected using the temperature of the object (here, the substrate). As a result, in the present embodiment, a normal predetermined thermistor can be accurately selected regardless of the presence or absence of abnormalities in the first and second thermistors 15a and 15b.

The process of determining the threshold value according to the detection temperature detected by the predetermined thermistor selected as described above and determining the thermistor 15 in which the abnormality has occurred using the determined threshold value is the first embodiment. Is similar to.

Next, the processing procedure executed by the determination device 20 according to the second embodiment will be described with reference to FIG. 7. FIG. 7 is a flowchart showing a processing procedure executed by the determination device 20 according to the second embodiment.

As shown in FIG. 7, the control unit 30 of the determination device 20 first acquires the temperature information of another object (step S10a). Next, the control unit 30 acquires the temperature detected by the first and second thermistors 15a and 15b (step S13).

The control unit 30 selects a normal predetermined thermistor based on the temperature of the substrate included in the temperature information of other objects and the detected temperatures of the first and second thermistors 15a and 15b (step S14a). Since steps S15 and subsequent steps are the same as those in the first embodiment, the description thereof will be omitted.

As described above, in the second embodiment, by using the temperature of the other object, a normal predetermined thermistor can be accurately selected from the plurality of thermistors 15. The residual effect is the same as in the first embodiment.

In the second embodiment described above, the object is a relay and the other object is a substrate, but this is merely an example and is not limited. That is, for example, the object and the other object may be of other types as long as the temperatures of the objects are similar to each other.

(Third Embodiment)
Next, the determination device 20 according to the third embodiment will be described. In the third embodiment, there are three or more thermistors 15, and when selecting a predetermined thermistor, the determination device 20 performs a majority voting process on the temperature detected by the plurality of thermistors 15.

Hereinafter, the determination device 20 according to the third embodiment will be described with reference to FIG. FIG. 8 is a block diagram showing the configuration of the battery system 1 including the determination device 20 according to the third embodiment.

As shown in FIG. 8, the battery system 1 includes a third thermistor 15c. Further, in the third embodiment, the characteristic information 42 of the first embodiment is removed in the storage unit 40.

The first to third thermistors 15a to 15c according to the third embodiment are provided on the LIB 14 and measure the temperature of the LIB 14. The first to third thermistors 15a to 15c each output signals indicating measurement results to the determination device 20.

In the above, the first to third thermistors 15a to 15c according to the third embodiment measure the temperature of the LIB 14, but the present invention is not limited to this. That is, the first to third thermistors 15a to 15c may measure the temperature of the same object, and may measure other temperatures such as the temperature of the relay and the substrate described above, for example.

In the determination device 20, the detection unit 32 of the control unit 30 detects the temperature detected by each thermistor 15a to 15c based on the signals input from the first to third thermistors 15a to 15c.

To be precise, the detection unit 32 receives signals from the first to third thermistors 15a to 15c indicating output voltages corresponding to the detection temperatures of the first to third thermistors 15a to 15c, respectively. The detection unit 32 detects the detection temperature in the first to third thermistors 15a to 15c based on the output voltage.

The detection unit 32 outputs the output voltage and the detection temperature of the first to third thermistors 15a to 15c to the selection unit 33, the determination unit 34, the determination unit 35, and the like.

The selection unit 33 performs a majority voting process on the detection temperatures detected by the plurality of thermistors 15 (here, the first to third thermistors 15a to 15c). Then, the selection unit 33 selects a predetermined thermistor based on the result of the majority voting process.

For example, the selection unit 33 compares the detection temperatures of the plurality of thermistors 15, counts the number of thermistors 15 indicating the same or similar detection temperatures, and selects a predetermined thermistor from among the plurality of thermistors 15. select.

As an example, in the selection unit 33, the detection temperature of the first thermistor 15a is "40 ° C", the detection temperature of the second thermistor 15b is "39 ° C", and the detection temperature of the third thermistor 15c is "20 ° C". In the case of, since the first and second thermistors 15a and 15b show the same or similar detection temperature, the first thermistor 15a from the first and second thermistors 15a and 15b is used as a predetermined thermistor. select. The selection unit 33 may select the second thermistor 15b as a predetermined thermistor.

In this way, the selection unit 33 can accurately select a normal predetermined thermistor by using the majority voting process.

The process of determining the threshold value according to the detection temperature detected by the predetermined thermistor selected as described above and determining the thermistor 15 in which the abnormality has occurred using the determined threshold value is the first embodiment. Is similar to.

Next, the processing procedure executed by the determination device 20 according to the third embodiment will be described with reference to FIG. FIG. 9 is a flowchart showing a processing procedure executed by the determination device 20 according to the third embodiment.

As shown in FIG. 9, the control unit 30 of the determination device 20 first acquires the temperature detected by the first to third thermistors 15a to 15c (step S13b). The control unit 30 performs a majority voting process on the detected temperatures of the first to third thermistors 15a to 15c, and selects a normal predetermined thermistor based on the result of the majority voting process (step S14b). Since steps S15 and subsequent steps are the same as those in the first embodiment, the description thereof will be omitted.

As described above, in the third embodiment, the plurality of thermistors 15 are three or more, and by using the majority voting process for the temperature detected by these thermistors 15, the number of thermistors 15 can be reduced. It is possible to accurately select a normal predetermined thermistor from. The residual effect is the same as in the first embodiment.

The above-mentioned first to third embodiments can be combined as appropriate. That is, for example, when the selection unit 33 selects a predetermined thermistor candidate by each method in combination with the first embodiment and the second embodiment, and the selected predetermined thermistor candidates match, the said Candidates may be configured to be selected as predetermined thermistors.

Further effects and variations can be easily derived by those skilled in the art. For this reason, the broader aspects of the invention are not limited to the particular details and representative embodiments expressed and described above. Therefore, various modifications can be made without departing from the spirit or scope of the general concept of the invention as defined by the appended claims and their equivalents.

1 Battery system 14 LIB
20 Judgment device 31 Acquisition unit 32 Detection unit 33 Selection unit 34 Decision unit 35 Judgment unit

Claims (5)

A selection unit that selects a normal predetermined thermistor from multiple thermistors,
A determination unit that determines a threshold value for determining an abnormal thermistor from the plurality of thermistors according to the temperature detected by the predetermined thermistor selected by the selection unit.
A determination device including a determination unit that determines a thermistor in which an abnormality has occurred among the plurality of thermistors using a threshold value determined by the determination unit. It is equipped with an acquisition unit that acquires characteristic information indicating the characteristics related to the temperature of the object that is the temperature detection target of the thermistor.
The selection unit
The first aspect of claim 1, wherein the predetermined thermistor is selected from the plurality of thermistors based on the characteristic information acquired by the acquisition unit and the temperature detected by each of the plurality of thermistors. Judgment device. It is provided with an acquisition unit for acquiring temperature information of other objects indicating the temperature of other objects existing within a predetermined range from the object whose temperature is to be detected by the thermistor.
The selection unit
The claim is characterized in that the predetermined thermistor is selected from the plurality of thermistors based on the temperature information of the other object acquired by the acquisition unit and the temperature detected by each of the plurality of thermistors. The determination device according to 1 or 2. There are three or more thermistors,
The selection unit
The determination according to any one of claims 1 to 3, wherein a majority voting process is performed on the temperature detected by the plurality of thermistors, and the predetermined thermistor is selected based on the result of the majority voting process. Device. A selection process that selects a normal predetermined thermistor from multiple thermistors,
A determination step of determining a threshold value for determining an abnormal thermistor from the plurality of thermistors according to the temperature detected by the predetermined thermistor selected by the selection step.
A determination method including a determination step of determining an abnormal thermistor from a plurality of thermistors using a threshold value determined by the determination step.

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