Cooler abnormality detection device

Abstract

To provide a cooler abnormality detection device with which it is possible to determine whether or not a cooling fin of the cooler for cooling electronic components is in an abnormal state.SOLUTION: The abnormality detection device comprises: a first temperature sensor provided to an air-cooling cooler having a cooling fin, for measuring a first temperature that is the temperature of the cooler; a second temperature sensor for measuring a physical quantity related to a second temperature that is the temperature of the electronic components that are constituent elements of an electrical circuit and are cooled by the cooler; and an ECU having a determination unit that determines that the cooling fin is in an abnormal state when a detection temperature difference Drd indicating the value of the second temperature obtained on the basis of the measured value of the second temperature sensor minus the first temperature that is the measured value of the first temperature sensor is smaller, by a threshold Tr or more, than a reference temperature difference Drs indicating the value of the second temperature when the cooling fin is in the normal state minus the first temperature.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to an abnormality detection device for a cooler. [Background technology]

[0002] Patent Document 1 below discloses a power conversion device that includes an electric circuit having a switching element and a cooler having cooling fins. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-47695 Summary of the Invention [Problem to be solved by the invention]

[0004] The invention of the above-mentioned Patent Document 1 cannot determine whether or not an abnormality has occurred in the cooling fins of the cooler that cools the switching elements.

[0005] SUMMARY OF THE INVENTION In consideration of the above, an object of the present invention is to provide a cooler abnormality detection device that can determine whether or not the cooling fins of a cooler that cools electronic components are in an abnormal state. [Means for solving the problem]

[0006] The cooler abnormality detection device of claim 1 is provided in an air-cooled cooler having cooling fins and comprises a first temperature sensor that measures a first temperature, which is the temperature of the cooler; a second temperature sensor that measures a physical quantity related to a second temperature, which is the temperature of an electronic component that is a component of an electrical circuit and is cooled by the cooler; and a judgment unit that judges that the cooling fins are in an abnormal state when a detected temperature difference, which is the value obtained by subtracting the first temperature, which is the measurement value of the first temperature sensor, from the second temperature obtained based on the measurement value of the second temperature sensor, is smaller by a threshold value or more than a reference temperature difference, which is the value obtained by subtracting the first temperature from the second temperature when the cooling fins are in a normal state.

[0007] The determination unit of the cooler abnormality detection device of claim 1 determines that the cooling fin is in an abnormal state when the detected temperature difference is smaller than the reference temperature difference by a threshold value or more. Here, the reference temperature difference is a value obtained by subtracting the first temperature from the second temperature when the cooling fin is in a normal state. Also, the detected temperature difference is a value obtained by subtracting the first temperature, which is the measurement value of the first temperature sensor, from the second temperature calculated based on the measurement value of the second temperature sensor.

[0008] When the cooling fins are in a normal state, the cooler performs the desired heat dissipation function. Here, "the cooling fins are in a normal state" refers to a state in which there is only a small amount of deposits on the surface of the cooling fins or no deposits at all on the surface of the cooling fins. When the cooling fins are in a normal state, the cooler performs the desired heat dissipation function, and the detected temperature difference is likely to be large. In other words, in this case, the detected temperature difference is unlikely to be smaller than the reference temperature difference by more than the threshold value.

[0009] On the other hand, when the cooling fins are in an abnormal state, the cooler cannot perform its intended heat dissipation function. Here, "the cooling fins are in an abnormal state" refers to a state in which the heat dissipation function of the cooling fins is significantly reduced due to a large amount of deposits adhering to the surface of the cooling fins, compared to when there is no deposit on the cooling fins. When the cooling fins are in an abnormal state, the cooler cannot perform its intended heat dissipation function, so the detected temperature difference is likely to be small. In other words, in this case, the detected temperature difference is likely to be a value smaller than the reference temperature difference by more than the threshold value.

[0010] The cooler abnormality detection device of claim 1 determines that the cooling fins are in an abnormal state when the detected temperature difference is smaller than the reference temperature difference by a threshold value or more. Therefore, the cooler abnormality detection device of claim 1 can determine whether the cooling fins of a cooler that cools electronic components are in an abnormal state. Therefore, for example, when an electric circuit operates abnormally due to an overheating of the electronic components, an operator can remove deposits from the cooling fins and return the electric circuit to a normal state.

[0011] The cooler abnormality detection device of claim 2 is the same as claim 1, and further includes an alarm device that notifies the user that the cooling fin is in the abnormal state when the judgment unit judges that the cooling fin is in the abnormal state.

[0012] The cooling device abnormality detection device of claim 2 includes an alarm device that notifies the user that the cooling fin is in an abnormal state when the determination unit determines that the cooling fin is in an abnormal state, so that an operator can return the abnormal electrical circuit to a normal state by removing the deposits from the cooling fin.

[0013] The cooler abnormality detection device described in claim 3 is, in claim 1 or claim 2, provided with reference temperature difference data which is data regarding the reference temperature difference when a reference power which is a predetermined amount of power is supplied to the electronic component, and when input power which is a power of a magnitude different from the reference power is supplied to the electronic component, the judgment unit corrects the reference temperature difference data based on the input power to generate corrected reference temperature difference data, and compares the corrected reference temperature difference data with the detected temperature difference, and if the detected temperature difference is smaller than the reference temperature difference defined by the corrected reference temperature difference data by more than the threshold value, judges that the cooling fin is in the abnormal state.

[0014] The cooler abnormality detection device of claim 3 can determine whether the cooling fins of the cooler that cools the electronic component are in an abnormal state when various levels of power are input to the electronic component. [Effects of the Invention]

[0015] As described above, the cooler abnormality detection device according to the present invention has the excellent effect of being able to determine whether or not the cooling fins of a cooler that cools electronic components are in an abnormal state. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a schematic perspective view of an e-axle of a vehicle equipped with a cooler abnormality detection device according to an embodiment; [Figure 2] FIG. 1 is a schematic cross-sectional view of a cooler and a switching element module of an e-axle. [Figure 3] FIG. 2 is a schematic perspective view of a packaged switching element that is a component of the switching element module. [Figure 4] FIG. 2 is a control block diagram of an ECU of a vehicle. [Figure 5] FIG. 2 is a functional block diagram of the ECU. [Figure 6] FIG. 10 is a diagram showing reference temperature difference data when a reference power is input to an inverter circuit in a stepwise manner. [Figure 7] FIG. 10 is a diagram showing a coefficient calculation map. [Figure 8] 10 is a diagram showing reference temperature difference data (corrected reference temperature difference data) when a power having a magnitude different from the reference power is input to the inverter circuit in a stepwise manner. FIG. [Figure 9] 4 is a flowchart showing a process executed by a CPU of an ECU. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, an embodiment of a cooler abnormality detection device 50 according to the present invention will be described with reference to the accompanying drawings. Note that the arrows UP, FR, and LH shown in the drawings indicate the upper side in the up-down direction, the front side in the front-to-back direction, and the left side in the left-to-right direction, respectively.

[0018] As shown in FIG. 1, a vehicle equipped with an abnormality detection device 50 has an e-axle 15. The e-axle 15 includes a case 17, an electric motor (not shown) as a drive source for the vehicle, a gear, an inverter circuit (an electric circuit, not shown), and a cooler 20. The gear, electric motor, and inverter circuit are housed within the case 17. The electric motor operates using power from a battery (not shown) supplied via the inverter circuit. An axle (not shown) that is linked to the electric motor via a gear and protrudes left and right from the case 17 is connected to one of the left and right front wheels and one of the left and right rear wheels (not shown). The inverter circuit converts battery power from direct current to alternating current and supplies it to the electric motor, and converts AC power generated by the electric motor into direct current and supplies it to the battery.

[0019] The air-cooled cooler 20 is a one-piece molded metal part. The cooler 20 includes a base 21 that forms the right side of the cooler 20 and is mostly housed in the case 17, and a plurality of cooling fins 22 that are provided on the left side surface of the base 21 and exposed to the left of the e-axle 15. The cooling fins 22 are aligned vertically with gaps formed between them.

[0020] 2, a first temperature sensor 25 is fixed to the left side surface of the base 21, positioned between the two cooling fins 22. In this embodiment, the first temperature sensor 25 is, for example, a thermistor, but a temperature sensor other than a thermistor may also be used. The first temperature sensor 25 detects the temperatures of the left side surface of the base 21 and the cooling fins 22 adjacent to the first temperature sensor 25. In other words, the first temperature sensor 25 detects a first temperature, which is the surface temperature of the cooler 20.

[0021] A switching element module 30 provided in an inverter circuit is provided on the back surface of the base 21 (the surface opposite to the cooling fin 22). The switching element module 30 is a component of the inverter circuit. The switching element module 30 has an element case 31, a plurality of packaged switching elements (electronic components) 33, and a second temperature sensor 34. The packaged switching elements 33 and the second temperature sensor 34 are provided inside the element case 31.

[0022] As shown in FIG. 3, the packaged switching element 33 includes a resin case package 33A, a semiconductor element 33B disposed inside the package 33A, and three terminals 33C extending from the semiconductor element 33B with ends protruding outside the package 33A. The semiconductor element 33B contains, for example, germanium or silicon. An IGBT chip, for example, can be used as the semiconductor element 33B. The terminals 33C of each packaged switching element 33 are connected to an inverter circuit.

[0023] In this embodiment, the second temperature sensor 34 is, for example, a diode-type temperature sensor, but may be a temperature sensor other than a diode-type temperature sensor. The second temperature sensor 34 detects a second temperature, which is the temperature of the packaged switching element 33. The element case 31 is fixed to the right side surface of the base 21 via, for example, a material with high thermal conductivity.

[0024] A display 12 (announcement device) (see FIG. 4) is provided on an instrument panel (not shown) of the vehicle.

[0025] 4, the ECU 35 includes a central processing unit (CPU) 35A, a read-only memory (ROM) 35B, a random access memory (RAM) 35C, a storage 35D, a communication I / F 35E, and an input / output I / F 35F. The CPU 35A, the ROM 35B, the RAM 35C, the storage 35D, the communication I / F 35E, and the input / output I / F 35F are connected to each other via an internal bus 35Z so as to be able to communicate with each other.

[0026] The CPU 35A is a central processing unit that executes various programs and controls each component. The CPU 35A reads programs from the ROM 35B or storage 35D and executes the programs using the RAM 35C as a work area. The CPU 35A controls each component and performs various arithmetic processing in accordance with the programs recorded in the ROM 35B or storage 35D.

[0027] The ROM 35B stores various programs and various data. The RAM 35C temporarily stores programs or data as a working area. The storage 35D is configured by a storage device such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive) and stores various programs and various data.

[0028] The communication I / F 35E is an interface for connecting via an external bus (not shown) to an ECU (not shown) other than the ECU 35. The interface uses a communication standard such as the CAN protocol.

[0029] The input / output I / F 35F is an interface for communicating with various devices, including the display 12, the first temperature sensor 25, the second temperature sensor 34, the electric motor, and the battery.

[0030] 5 is a block diagram showing an example of the functional configuration of the ECU 35. The ECU 35 has, as its functional configuration, a first abnormality determination unit (determination unit) 351, a second abnormality determination unit 352, and a notification control unit 353. The first abnormality determination unit 351, the second abnormality determination unit 352, and the notification control unit 353 are realized by the CPU 35A reading and executing programs stored in the ROM 35B.

[0031] The first abnormality determination unit 351 determines whether the cooling fins 22 of the cooler 20 are in a normal state or an abnormal state. Here, the normal state of the cooling fins 22 refers to a state in which there is only a small amount of deposits on the surface of the cooling fins 22 or no deposits at all on the surface of the cooling fins 22. The deposits may be composed of at least one of solidified mud, dirt, and dust. When each cooling fin 22 is in a normal state, the cooler 20 performs its intended heat dissipation function. Furthermore, the abnormal state of each cooling fin 22 refers to a state in which the heat dissipation function of the cooler 20 is significantly reduced due to a large amount of deposits on the surface of the cooling fins 22, compared to when there are no deposits on the cooling fins 22.

[0032] The first abnormality determination unit 351 determines whether the cooling fin 22 is in a normal state or an abnormal state using the surface temperature of the cooler 20 detected by the first temperature sensor 25, the temperature of the packaged switching element 33 detected by the second temperature sensor 34, the reference temperature difference data 40 shown in Figure 6, and the coefficient calculation map 45 shown in Figure 7.

[0033] The reference temperature difference data 40 shown in FIG. 6 represents the reference temperature difference Drs when a reference power WS, which is a predetermined amount of power (watts), is supplied as a step input to the switching element module 30 (packaged switching element 33) on the inverter circuit. The reference temperature difference data 40 is recorded in ROM 35B. The reference temperature difference Drs is a value obtained by subtracting the first temperature, which is the detection value of the first temperature sensor 25, from the second temperature, which is the detection value of the second temperature sensor 34, when the cooling fins 22 of the cooler 20 are in a normal state and the first temperature sensor 25 and the second temperature sensor 34 are functioning normally. The curve shown by the two-dot chain line in FIG. 6 represents the limit value Drlm, which is a value smaller than the reference temperature difference Drs by the threshold value Tr. Data related to the threshold value Tr is recorded in ROM 35B. The threshold value Tr and the limit value Drlm are part of the reference temperature difference data 40. 6, t1 is the time when the first reference time has elapsed since the time (=0) when the reference power WS was stepped up, and t2 is the time when the second reference time has elapsed since the time when the reference power WS was stepped up. The second reference time is longer than the first reference time.

[0034] When power of the same magnitude as the reference power WS is actually input to the switching element module 30 (package-type switching element 33), the first abnormality determination unit 351 determines whether the detected temperature difference Drd, which is the value obtained by subtracting the first temperature, which is the value detected by the first temperature sensor 25, from the second temperature, which is the value detected by the second temperature sensor 34, between the time t1 when a first reference time has elapsed since the time (=0) when the input of this power ended and the time t2 when a second reference time has elapsed, is included in the region between the reference temperature difference Drs and the limit value Drlm between t1 and t2. For example, if the detected temperature difference Drd when power of the same magnitude as the reference power WS is input to the switching element module 30 has the shape shown by the dashed line in FIG. 6, the first abnormality determination unit 351 determines that the cooling fins 22 of the cooler 20 are in an abnormal state. On the other hand, if the detected temperature difference Drd when power of the same magnitude as the reference power WS is input to the switching element module 30 is included in the area between the reference temperature difference Drs and the limit value Drlm between t1 and t2, the first abnormality judgment unit 351 judges that the cooling fins 22 of the cooler 20 are in a normal state.

[0035] When the cooling fins 22 are in a normal state, the cooler 20 performs the desired heat dissipation function. Therefore, when the cooling fins 22 are in a normal state, the detected temperature difference Drd is likely to be large. In other words, in this case, the detected temperature difference Drd is unlikely to be smaller than the reference temperature difference Drs by more than the threshold value Tr. In other words, in this case, the detected temperature difference Drd is likely to be included in the region between the reference temperature difference Drs and the limit value Drlm between t1 and t2.

[0036] On the other hand, when the cooling fins 22 are in an abnormal state, the cooler 20 cannot perform the desired heat dissipation function. That is, when the cooling fins 22 are in an abnormal state, the heat dissipation function of the cooling fins 22 is significantly reduced compared to when the cooling fins 22 are in a normal state. Therefore, when the cooling fins 22 are in an abnormal state, the detected temperature difference Drd is likely to be small. Therefore, in this case, the detected temperature difference Drd is likely to be smaller than the reference temperature difference Drs by the threshold value Tr or more. That is, in this case, the detected temperature difference Drd is likely to be below the limit value Drlm between t1 and t2.

[0037] Furthermore, the magnitude of the power actually input to the switching element module 30 is not necessarily the same as the reference power WS. For this reason, the coefficient calculation map 45 shown in FIG. 7 is recorded in the ROM 35B. The coefficient calculation map 45 represents the relationship between the magnitude of the power input to the switching element module 30 and the coefficient CE. The coefficient calculation map 45 represents that the coefficient CE is "1" when the reference power WS is supplied to the switching element module 30. Furthermore, the coefficient calculation map 45 represents that the coefficient CE is less than 1 when power less than the reference power WS is supplied to the switching element module 30, and that the coefficient CE is greater than 1 when power greater than the reference power WS is supplied to the switching element module 30.

[0038] When the magnitude of the power actually input to the switching element module 30 differs from the reference power WS, the first abnormality determination unit 351 obtains the corrected reference temperature difference data 41 shown in FIG. 8 by multiplying the reference temperature difference Drs, the limit value Drlm, and the threshold value Tr by a coefficient CE obtained by applying the magnitude of the power input to the coefficient calculation map 45 of FIG. 7. For example, when the magnitude of the power actually input to the switching element module 30 is input power W1 that is smaller than the reference power WS, the coefficient CE is K, which is smaller than 1. The corrected reference temperature difference data 41 is obtained by multiplying the reference temperature difference Drs, the limit value Drlm, and the threshold value Tr by K, and includes the corrected reference temperature difference Drs, the limit value Drlm, and the threshold value Tr. For example, when the detected temperature difference Drd when input power W1 is input to the switching element module 30 has the shape shown by the dashed line in FIG. 8, the first abnormality determination unit 351 determines that the cooling fin 22 of the cooler 20 is in an abnormal state. On the other hand, if the detected temperature difference Drd when input power W1 is input to the switching element module 30 is included in the area between the reference temperature difference Drs and the limit value Drlm between t1 and t2, the first abnormality judgment unit 351 judges that the cooling fins 22 of the cooler 20 are in a normal state.

[0039] The second abnormality determination unit 352 compares the second temperature detected by the second temperature sensor 34 with the element determination threshold value recorded in ROM 35B, and determines that there is an abnormality in the packaged switching element 33 (switching element module 30) if the second temperature is equal to or higher than the element determination threshold value.

[0040] The notification control unit 353 displays a predetermined notification message on the display 12 when the first abnormality determination unit 351 determines that the cooling fins 22 are in an abnormal state. This notification message is a message that makes the vehicle occupant aware that the cooler 20 is in a state where it cannot perform its intended heat dissipation function due to deposits adhering to the cooling fins 22 of the cooler 20. For example, the notification message is a message saying, "Please remove dirt from the cooling fins to return the cooler to a normal state." However, the notification message may be a different message as long as it makes the occupant aware that the cooler 20 is in a state where it cannot perform its intended heat dissipation function due to deposits adhering to the cooling fins 22.

[0041] Of the above-described configuration, the display 12, the first temperature sensor 25, the second temperature sensor 34, and the ECU 35 are components of the cooler abnormality detection device 50.

[0042] (Action and effect) Next, the operation and effects of this embodiment will be described.

[0043] Next, a description will be given of the processing executed by the CPU 35A of the ECU 35. The CPU 35A repeatedly executes the processing of the flowchart shown in FIG.

[0044] In step S10 (hereinafter, the word "step" will be omitted), the CPU 35A determines whether or not the first temperature has been acquired from the first temperature sensor 25 and the second temperature has been acquired from the second temperature sensor .

[0045] If the determination in S10 is Yes, the CPU 35A proceeds to S11, where it compares the detected temperature difference Drd calculated based on the first temperature and the second temperature with the reference temperature difference data 40 (corrected reference temperature difference data 41).

[0046] Next, the CPU 35A proceeds to S12 to determine whether the detected temperature difference Drd is smaller than the reference temperature difference Drs by the threshold value Tr or more. In other words, the CPU 35A determines whether the cooling fins 22 of the cooler 20 are in an abnormal state.

[0047] If the determination in S12 is Yes, the CPU 35A proceeds to S13 and causes the display 12 to display a notification message.

[0048] If the result of the determination in S12 is No or if the process of S13 has been completed, the CPU 35A proceeds to S14 and determines whether the second temperature is equal to or higher than the element determination threshold value.

[0049] If the determination in S14 is Yes, the CPU 35A proceeds to S15 and displays a predetermined message on the display 12. This message may be, for example, a message saying "There is an abnormality in the switching element."

[0050] When the determination in S10 or S14 is No, or when the process of S15 is completed, the CPU 35A temporarily ends the process of this flowchart.

[0051] As described above, the cooler abnormality detection device 50 of this embodiment uses the first temperature and the second temperature to determine whether the cooling fins 22 of the cooler 20 are in an abnormal state. That is, when the detected temperature difference Drd is smaller than the reference temperature difference Drs by at least the threshold value Tr, the abnormality detection device 50 determines that the cooling fins 22 are in an abnormal state. Therefore, when the second temperature detected by the second temperature sensor 34 is high, the abnormality detection device 50 can determine whether the high temperature of the switching element module 30 is caused by an abnormal state of the cooling fins 22. Therefore, if the inverter circuit operates abnormally due to the high temperature of the switching element module 30, an operator can remove deposits from the cooling fins 22, which may prevent the inverter circuit from operating abnormally. That is, the risk of replacing a healthy inverter circuit with a new inverter circuit is reduced. Furthermore, if the detected temperature difference Drd is not smaller than the reference temperature difference Drs by more than the threshold value Tr and the second temperature is greater than or equal to the element judgment threshold value, the abnormality detection device 50 determines that the cause of the high temperature of the switching element module 30 is the switching element module 30 itself.

[0052] If the detected temperature difference Drd is smaller than the reference temperature difference Drs by at least the threshold value Tr and the second temperature is equal to or greater than the element determination threshold, it is possible that the cooling fins 22 are in an abnormal state and that the switching element module 30 itself is not the cause of the high temperature, or that the cooling fins 22 are in an abnormal state and that the switching element module 30 itself is the cause of the high temperature. Therefore, in this case, it is advisable to first remove any dirt from the cooling fins 22. If the second temperature remains equal to or greater than the element determination threshold even after the dirt from the cooling fins 22 is removed, the packaged switching element 33 should be replaced with a new packaged switching element 33.

[0053] Furthermore, the cooler abnormality detection device 50 acquires corrected reference temperature difference data 41, which is reference temperature difference data appropriate for the power actually input to the switching element module 30, based on the reference temperature difference data 40 and the coefficient CE, and determines whether the cooling fins 22 are in an abnormal state using this corrected reference temperature difference data 41. Therefore, when various amounts of power are input to the switching element module 30, the abnormality detection device 50 can determine whether abnormal operation of the inverter circuit caused by the switching element module 30 is due to an abnormality in the cooling fins 22.

[0054] Furthermore, when it is determined that the cooling fins 22 are in an abnormal state, the cooler abnormality detection device 50 displays a notification message indicating that the cooling fins 22 are in an abnormal state on the display 12. This allows a vehicle occupant to remove deposits from the cooling fins 22, thereby restoring the inverter circuit in an abnormal state to a normal state.

[0055] Although the abnormality detection device for a cooler according to the embodiment has been described above, appropriate design changes can be made without departing from the spirit of the present invention.

[0056] For example, the present invention may be applied to an electric circuit other than an inverter circuit, and may be applied to a device other than a vehicle.

[0057] Regardless of the amount of power actually input to the switching element module 30, the abnormality detection device 50 may determine whether the cooling fin 22 is in an abnormal state based on the reference temperature difference data 40 and the detected temperature difference Drd without using the coefficient calculation map 45.

[0058] The vehicle may be equipped with a speaker, and when it is determined that the cooling fin 22 is in an abnormal state, the speaker may output a sound representing the notification message.

[0059] The abnormality detection device 50 may be provided with a plurality of second temperature sensors 34 that measure the temperatures of the packaged switching elements 33. In this case, for example, the average value of the detection values ​​of the second temperature sensors 34 becomes the second temperature. According to this modification, the detection accuracy of the second temperature is increased, and therefore it is possible to determine with higher accuracy whether the cooling fin 22 is in an abnormal state.

[0060] The second temperature sensor 34 may be provided outside the element case 31. For example, the second temperature sensor 34 may be fixed to the outer surface of the element case 31 or to the right side of the base 21 near the switching element module 30. For example, when the second temperature sensor 34 is fixed to the outer surface of the element case 31, the second temperature sensor 34 acquires the temperature (physical quantity) of the element case 31, and the CPU 35A acquires the second temperature based on a map (not shown) that defines the relationship between the temperature of the element case 31 and the temperature of the packaged switching element 33 and the temperature of the element case 31. In this case, the CPU 35A may also acquire the second temperature by calculation based on the temperature of the element case 31 and a coefficient that defines the relationship between the temperature of the element case 31 and the temperature of the packaged switching element 33. For example, when the second temperature sensor 34 is fixed near the switching element module 30 on the right side of the base 21, the second temperature sensor 34 acquires the temperature (physical quantity) of the right side of the base 21, and the CPU 35A acquires the second temperature based on a map (not shown) that defines the relationship between the temperature of the right side of the base 21 and the temperature of the packaged switching element 33, and the temperature of the right side of the base 21. In this case, the CPU 35A may also acquire the second temperature by calculation based on a coefficient that defines the relationship between the temperature of the right side of the base 21 and the temperature of the packaged switching element 33, and the temperature of the right side of the base 21.

[0061] Alternatively, instead of the switching element module 30, a single packaged switching element 33 may be provided in the inverter circuit, and the package 33A may be fixed to the right side surface of the base 21 via a highly thermally conductive material. In this case, the semiconductor element 33B of the packaged switching element 33 corresponds to the "electronic component." In this case, for example, a second temperature sensor 34 is fixed to the outer surface of the package 33A, and the CPU 35A acquires the second temperature based on a map (not shown) that defines the relationship between the temperature (physical quantity) of the package 33A and the temperature of the semiconductor element 33B, and the temperature of the package 33A acquired by the second temperature sensor 34.

[0062] The electronic component of the present invention may be an electronic component separate from the switching element module 30 or the packaged switching element 33 . [Explanation of symbols]

[0063] 12 Display (alarm device) 20 Cooler 22 Cooling fins 25 First temperature sensor 30 Switching element module 33 Packaged switching elements (electronic components) 33B Semiconductor elements (electronic components) 34 Second temperature sensor 351 First abnormality determination section (determination section) 40 Reference temperature difference data 41 Correction reference temperature difference data 50 Anomaly detection device Drs reference temperature difference Drlm Threshold Drd Detected Temperature Difference

Claims

1. a first temperature sensor provided in an air-cooled cooler having cooling fins, the first temperature sensor measuring a first temperature that is a temperature of the cooler; a second temperature sensor for measuring a physical quantity related to a second temperature, which is the temperature of an electronic component that is a component of an electric circuit and is cooled by the cooler; a determination unit that determines that the cooling fin is in an abnormal state when a detected temperature difference, which is a value obtained by subtracting the first temperature, which is a measurement value of the first temperature sensor, from the second temperature obtained based on the measurement value of the second temperature sensor, is smaller than a threshold value or more of a reference temperature difference, which is a value obtained by subtracting the first temperature from the second temperature when the cooling fin is in a normal state; A cooling device for detecting abnormalities.

2. 2. The abnormality detection device for a cooler according to claim 1, further comprising an alarm device that, when the determination unit determines that the cooling fin is in the abnormal state, notifies the user that the cooling fin is in the abnormal state.

3. a reference temperature difference data that is data relating to the reference temperature difference when a reference power that is a predetermined amount of power is supplied to the electronic component; 3. The cooler abnormality detection device of claim 1, wherein when input power having a magnitude different from the reference power is supplied to the electronic component, the judgment unit corrects the reference temperature difference data based on the input power to generate corrected reference temperature difference data, compares the corrected reference temperature difference data with the detected temperature difference, and determines that the cooling fin is in the abnormal state if the detected temperature difference is smaller than the reference temperature difference defined by the corrected reference temperature difference data by more than the threshold value.

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