JP7255577B2 - OVERHEAT DETECTION DEVICE FOR ELECTRICAL FACILITIES, AND OVERHEAT DETECTION METHOD FOR ELECTRICAL FACILITIES - Google Patents

Description

The present invention relates to an overheat detection device for electrical equipment and an overheat detection method for electrical equipment.

Patent Document 1 discloses an overheat detection device (temperature monitoring device) for determining aged deterioration of electrical equipment. This prior art overheat detection device divides a monitoring target region into a matrix and includes an infrared array sensor (infrared light receiving device) that detects the temperature of each division from the intensity of infrared rays. The overheat detection device of the prior art thereby acquires the temperature of each section of the monitored area and detects the occurrence of overheating in the monitored area of the electrical equipment.

Utility model registration No. 3210706 (issued on June 1, 2017)

However, in the overheat detection device of Patent Document 1, the temperature of each section is detected according to the infrared intensity received by each pixel of the detection section of the infrared array sensor corresponding to each section. If the overheating part of the electrical equipment is a local area within a section, the average temperature in each section is obtained as the temperature of each section, which reduces the detection sensitivity to overheating or overheating. There is a problem that it is difficult to set a threshold for determining that.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems. The object is to realize a detection device.

In order to solve the above problems, an overheat detection apparatus for electrical equipment according to one aspect of the present invention includes an infrared array sensor that detects temperature by dividing a monitoring target area of the electrical equipment into a matrix, and the infrared array sensor: a reading unit for acquiring the temperature of each section detected by the temperature rise value calculating unit for calculating the temperature rise value of each of the sections from the temperature of each section; , a threshold calculation unit that repeatedly obtains the temperature rise value of each of the sections and calculates the threshold based on the maximum value thereof; and an overheat detection unit that detects overheating of the electrical equipment by comparing the temperature rise value of each of the sections with the threshold value.

An overheat detection device for electrical equipment according to another aspect of the present invention includes an infrared array sensor that detects the temperature by dividing a monitoring target area of the electrical equipment into a matrix, and the temperature of each section detected by the infrared array sensor. a temperature rise value calculator for calculating the temperature rise value of each of the sections from the temperature of each of the sections; and the temperature of each of the sections during a predetermined period for determining a threshold value. a threshold calculation unit that repeatedly acquires an increase value and calculates each threshold based on the maximum value of the temperature increase value in each of the sections; an overheat detection unit that acquires a temperature rise value and compares the temperature rise value of each of the divisions with the respective threshold values to detect overheating of the electrical equipment.

An overheat detection method for electrical equipment according to an aspect of the present invention divides a monitoring target area of the electrical equipment into a matrix and detects the temperature of each segment from the temperature of each segment detected by an infrared array sensor. The temperature rise value calculation substep is used as the substep of calculating the rise value, and the temperature rise value of each of the categories calculated by the temperature rise value calculation substep is repeatedly obtained for a predetermined period of time, and the maximum value thereof is used as a threshold value. and comparing the temperature rise value of each of the categories calculated by the temperature rise value calculation sub-step with the threshold value to detect overheating of the electrical equipment. .

According to another aspect of the present invention, there is provided a method for detecting overheating of electrical equipment, which divides a monitoring target area of the electrical equipment into a matrix and detects the temperature of each segment from the temperature of each segment detected by an infrared array sensor. The sub-step of calculating the temperature rise value is defined as a temperature rise value calculation substep, and the temperature rise value of each of the sections calculated by the temperature rise value calculation substep is repeatedly obtained for a predetermined period, and in each of the sections Comparing the temperature rise value of each of the categories calculated by the step of calculating each threshold value based on the maximum value of the temperature rise value of and the temperature rise value calculation substep with the respective threshold value and detecting overheating of the electrical equipment.

The overheat detection device according to each aspect of the present invention may be implemented using a computer. In this case, the overheat detection device is operated by operating the computer as each part (software element) included in the overheat detection device. An overheat detection control program for an overheat detection device that is realized using a computer, and a computer-readable recording medium recording it are also included in the scope of the present invention.

According to the overheat detection device for electrical equipment or the overheat detection method for electrical equipment according to any of the above aspects of the present invention, even if the infrared array sensor does not sufficiently detect local overheating in the section, overheating occurs. can be determined accurately.

1 is a block diagram showing the configuration of an overheat detection device according to Embodiment 1 of the present invention; FIG. It is a figure which shows the hardware constitutions of the overheat detection apparatus which concerns on Embodiment 1 of this invention. FIG. 4 is a diagram showing an infrared array sensor and a monitored area when the overheat detection device according to Embodiment 1 of the present invention monitors electrical equipment; FIG. 4 is a diagram for explaining division of a monitoring target area of the overheat detection device according to Embodiment 1 of the present invention; 4 is a flowchart for explaining the operation of the overheat detection device according to Embodiment 1 of the present invention; 4 shows threshold calculation processing. 4 is a flowchart for explaining the operation of the overheat detection device according to Embodiment 1 of the present invention; A temperature rise value calculation process, which is a subroutine, is shown. 4 is a flowchart for explaining the operation of the overheat detection device according to Embodiment 1 of the present invention; 4 shows overheating detection processing. 9 is a flowchart for explaining the operation of the overheat detection device according to Embodiment 2 of the present invention; 4 shows threshold calculation processing. 9 is a flowchart for explaining the operation of the overheat detection device according to Embodiment 2 of the present invention; 4 shows overheating detection processing.

[Embodiment 1]
One embodiment of the present invention will be described in detail below with reference to FIGS. An overheat detection device 1 according to the first embodiment is a device that monitors a monitoring target area 11 set for an electrical equipment 12 or the like. If overheating occurs in at least a part of the area to be monitored 11, the overheat detection device 1 detects and notifies it.

<Configuration of overheat detector>
FIG. 1 is a block diagram showing a schematic configuration of an overheat detection device 1 according to Embodiment 1. As shown in FIG. The overheat detection device 1 includes a calculation section 2 , an infrared array sensor 3 and a communication section 4 . The infrared array sensor 3 is a device that divides the monitored area 11 into a matrix and detects the temperature Tn of each division Gn. Here, the symbol n of each partition Gn indicates the index of the partition.

The infrared array sensor 3 has a detection section provided with a plurality of pixels each receiving far infrared rays (heat rays) emitted from each section Gn. The infrared array sensor 3 calculates and outputs the temperature Tn of each section Gn from the amount of infrared light received by each pixel. In the following, as a specific example of the infrared array sensor 3, a case of using a 64-pixel infrared array sensor capable of detecting temperature by dividing the monitored area into an 8×8 matrix will be described.

As shown in FIG. 1 , the calculation unit 2 is provided with functional blocks of a reading unit 21 , a temperature rise value calculation unit 22 , an overheat detection unit 23 , a threshold value calculation unit 24 and a control unit 25 . The reading unit 21 is a functional block that accesses the infrared array sensor 3 and reads the temperature Tn of each section Gn detected by the infrared array sensor 3 .

The temperature rise value calculator 22 is a functional block that calculates the temperature rise value ΔTn of each section Gn from the temperature Tn of each section Gn read by the reading section 21 . The overheat detection unit 23 is a functional block that executes overheat detection processing in cooperation with other functional blocks. The threshold calculator 24 is a functional block that executes threshold calculation processing in cooperation with other functional blocks. The control unit 25 is a functional block that collectively controls these functional blocks. The functions of these functional blocks will be described in more detail in the description of the operation of the overheat detection device 1, which will be described later.

The communication unit 4 is a communication interface that communicates with the external device 90 . Here, the external device 90 is usually installed isolated from the installation site of the electrical equipment 12 to be monitored. The communication unit 4 may communicate with the external device 90 via a network such as a LAN (Local Area Network) or the Internet. The connection to the external device 90 or network may be wired or wireless.

<Hardware configuration of overheat detector>
FIG. 2 shows the hardware configuration of the overheat detection device 1 according to the first embodiment. In particular, FIG. 2 shows an expanded hardware configuration for realizing the computing unit 2 composed of the functional blocks shown in FIG.

As shown in FIG. 2 , the computing unit 2 is provided with a CPU 5 (Central Processing Unit), a nonvolatile memory 6 and a memory 8 . The nonvolatile memory 6 stores a control program 7 which is software that realizes each function of the calculation unit 2 by being read and executed by the CPU 5 .

In the memory 8, various information acquired by the calculation unit 2 and at least a part of the developed control program 7 necessary for the CPU 5 to execute the control program 7 can be temporarily or long term stored. Alternatively, in the memory 8, other data necessary for the CPU 5 to execute the control program 7 and various information calculated by the CPU 5 executing the control program 7 can be temporarily or long term stored. .

<Monitoring target area>
FIG. 3 is a diagram showing how the overheat detection device 1 monitors the monitored area 11 of the electrical equipment 12 using the infrared array sensor 3. As shown in FIG. As illustrated, in Embodiment 1, a specific example is shown in which the electrical equipment 12 includes the busbars 13 and the monitoring target area 11 is set to an area including the fastening portions 14 of the busbars 13 . That is, below, an example of monitoring whether the fastening portion 14 of the bus bar 13 is loosened and the resistance of the fastening portion 14 is increased, or whether abnormal overheating is caused by an abnormal current is shown. .

FIG. 4 shows a section 15 of the monitored area 11 corresponding to each pixel of the sensing portion of the infrared array sensor 3 . As described above, the monitoring target area 11 is divided into an 8×8 matrix. Here, each section 15 is represented by the symbol Gn (n: 1 to 64). The infrared array sensor 3 outputs the temperature Tn of each section Gn of the monitored area 11 .

Some of the segments 15 are out of the busbars 13 that are monitored. In FIG. 4, sections G1 to G8 and sections G57 to G64 are sections separated from the bus bar 13. In FIG. The infrared array sensor 3 detects the temperature of the partition wall, board surface, housing, or the like of the electrical equipment 12 for these sections 15 .

<Operation of overheat detector>
The overheat detection device 1 executes a threshold calculation process (a step of calculating a threshold K) or an overheat monitoring process (a step of detecting overheating of electrical equipment) based on an instruction from the external device 90 received through the communication unit 4. .

The overheating monitoring process is an operation in which the overheating detection device 1 monitors the occurrence of overheating in the electrical equipment 12 . The threshold calculation process is an operation for calculating a threshold K used as a criterion for judging overheating when the overheating detection device 1 performs the overheating monitoring process. Note that the overheat detection device 1 may be configured so that the overheat monitoring process is automatically executed subsequently after the threshold value calculation process is executed. Each process is described in detail below.

<Threshold calculation process>
FIG. 5 is a flow chart showing threshold calculation processing executed by the overheat detection device 1 according to the first embodiment. When the control unit 25 of the calculation unit 2 receives an instruction to execute the threshold calculation process from the external device 90 through the communication unit 4, it controls each part of the calculation unit 2 to cause the overheat detection device 1 to perform the threshold calculation process. let it start.

Step S101: When the threshold calculation process is started, the threshold calculator 24 first acquires the start time.

Step S102: Subsequently, the overheat detector 1 executes temperature rise value calculation processing. The temperature rise value calculation process is a process (subroutine) for calculating the temperature rise value ΔTn of each segment Gn, and the details thereof will be described later. The index of the number of repetitions of step S102 is denoted by i.

Step S103: Subsequently, the threshold calculator 24 determines whether or not a predetermined period of time, for example, two weeks, has passed since the start time. Here, the predetermined period is a predetermined period during which the overheat detection device 1 observes the electrical equipment 12 in order to determine the threshold value K. FIG. If it is determined that two weeks have passed (YES in S103), the flow proceeds to step S105. Otherwise (NO in S103), the flow proceeds to step S104.

Note that the predetermined period of two weeks is an example, and the period is not limited to this. However, since the power load of the electrical equipment 12 tends to follow a similar pattern for each day of the week, the period for determining the threshold K is preferably one week or more.

Step S104: The threshold calculator 24 determines whether or not a predetermined period of time, for example, one hour, has passed since the most recent temperature rise value calculation process. Here, the predetermined time is a repetition cycle in which the overheat detection device 1 calculates the temperature rise value ΔTn in the threshold value calculation process. Note that the predetermined time of one hour is an example, and is not limited to this.

If it is determined that one hour has passed (YES in S104), the flow returns to step S102. This is because the overheat detection device 1 executes the temperature rise value calculation process again. Otherwise (NO in S104), the flow returns to step S103. This is because the overheat detector 1 waits until the predetermined time elapses.

Step S105: After a predetermined period of time has passed since the start time, the flow reaches step S105. The threshold calculation unit 24 calculates the maximum value as the maximum temperature rise value ΔTmax from among the temperature rise values ΔTn(i) repeatedly obtained for each section Gn (n: 1 to 64).

Step S106: Subsequently, the threshold calculator 24 calculates the threshold K from the relational expression K=A×ΔTmax+B. Here, the likelihood coefficient A is a coefficient of 1 or more, and about 1 to 2 is particularly preferable. A constant B is a constant of 0 or more in consideration of temperature measurement errors in the infrared array sensor 3 . The constant B is particularly preferably about 0 to 5°C. Next, the flow of the threshold calculation process ends.

<Temperature Rise Value Calculation Processing (Subroutine)>
FIG. 6 is a flowchart showing a subroutine of temperature rise value calculation processing (temperature rise value calculation substep). The temperature rise value calculation process will be described below with reference to the flowchart of FIG.

Step ST1: The reading unit 21 acquires the temperature Tn (n: 1 to 64) of each section Gn detected by the infrared array sensor 3. FIG.

Step ST2: Subsequently, the temperature rise value calculation unit 22 extracts the lowest five temperatures from the temperatures Tn of each section Gn acquired by the reading unit 21 . Then, normally, in FIG. 4, these temperatures are extracted from the sections G1 to G8 and G57 to G64, which are separated from the busbar 13 and correspond to the partition wall, board surface, housing, etc. of the electrical equipment 12.

Step ST3: Subsequently, the temperature rise value calculation unit 22 calculates the average value of the extracted five lowest temperatures and sets it as the reference temperature Ta. Note that the number of extractions is an example, and is not limited to five. The number of extractions is preferably within the range of 5% to 20% of the number of segments 15 of the monitored area 11, that is, the number of pixels of the infrared array sensor 3. FIG.

Step ST4: Subsequently, the temperature rise value calculator 22 calculates a temperature rise value ΔTn (n: 1 to 64) by subtracting the reference temperature Ta from the temperature Tn in each section Gn. That is, the temperature rise value ΔTn is calculated from the relational expression ΔTn=Tn−Ta. Then, the temperature rise value of each section Gn is calculated with reference to locations that normally do not generate heat, such as partition walls, board surfaces, and housings of the electrical equipment 12, which are considered to be close to the ambient temperature. Next, the flow (subroutine) of the temperature rise value calculation process ends.

<Overheat monitoring process>
FIG. 7 is a flowchart showing overheating monitoring processing executed by the overheating detection device 1 according to the first embodiment. When the control unit 25 of the calculation unit 2 receives an instruction to execute the overheating monitoring process from the external device 90 through the communication unit 4, it controls each part of the calculation unit 2 to cause the overheating detection device 1 to perform the overheating monitoring process. let it start.

Step S201: When the overheat monitoring process is started, the overheat detector 23 determines whether or not the threshold value K has not yet been calculated and set. If it is determined that the threshold K has not been set (YES in S201), the flow proceeds to step S202. Otherwise (NO in S201), the flow proceeds to step S203.

Step S202: The overheat detection unit 23 notifies the external device 90 through the communication unit 4 that the threshold value K has not been set. This is because the overheat monitoring process cannot be executed if the threshold value K is not set. Then, the flow of the overheat monitoring process ends.

Step S203: The overheat detection device 1 executes temperature rise value calculation processing. The temperature rise value calculation process is the above-described process (subroutine) described using FIG. 6 for calculating the temperature rise value ΔTn of each section Gn.

Step S204: Subsequently, the overheat detector 23 compares the temperature rise value ΔTn (n: 1 to 64) of each section Gn with the threshold K. If the temperature rise value ΔTn of each section Gn is equal to or greater than the threshold value K, that is, if ΔTn≧K is satisfied (YES in S204), the flow proceeds to step S205. Otherwise (NO in S204), the flow proceeds to step S206.

Step S205: The overheat detector 23 determines that overheating has occurred. This is because a temperature rise equal to or greater than the threshold value K was recognized. Flow then proceeds to step S207.

Step S206: The overheat detector 23 determines that overheating has not occurred. This is because no temperature rise exceeding the threshold value K was observed. Flow then proceeds to step S207.

Step S<b>207 : The overheat detection unit 23 notifies the external device 90 of the determination result through the communication unit 4 .

Step S<b>208 : Subsequently, the overheat detection unit 23 determines whether or not an instruction to stop the overheat monitoring process from the external device 90 has been received through the communication unit 4 . If it is determined that the signal has been received (YES in S208), then the flow of the overheat monitoring process ends. Otherwise (NO in S208), the flow proceeds to step S209.

Step S209: The overheat detector 23 determines whether or not a predetermined time has passed since the most recent temperature rise value calculation process. Here, the predetermined time is a monitoring interval for trying to detect overheating in the overheating monitoring process. The predetermined time can be, for example, 5 minutes.

If it is determined that the predetermined time has passed (YES in S209), the flow returns to step S203. This is because the processing after the temperature rise value calculation processing is repeated again. Otherwise (NO in S209), the flow returns to step S208. This is because the overheat detector 1 waits until the predetermined time elapses.

<Example>
When the temperature rise value ΔTn of each section Gn was observed while the predetermined period of the threshold value calculation process, that is, the learning period was two weeks, the maximum temperature rise value ΔTmax was 5°C. The likelihood coefficient A was set to 2, the constant B was set to 0, and the threshold K was set to 10°C.

In this case, when the temperature rise value ΔTn is equal to the threshold value K at which the temperature rise value ΔTn is determined to be abnormal during monitoring, the bus bar 13 has twice the amount of heat generated in the case of the maximum temperature rise value ΔTmax in the normal operating state. Since the amount of heat generated is proportional to the resistance value, if the temperature rise is due to an increase in contact resistance due to loosening of the fastening portion 14 or the like, overheating is determined when the contact resistance is approximately doubled. In addition, since the amount of heat generated is proportional to the square of the current, if the temperature rise is caused by an abnormal current, overheating will be determined if the current flowing through the bus bar 13 is 1.4 times or more that of the normal operating state. Become.

<Action/effect>
According to the overheat detection device of the first embodiment, the temperature rise value ΔTn in each section Gn of the monitored area 11 is calculated. The reference temperature Ta, which serves as the reference, is calculated from the lower data of the temperature Tn detected by the infrared array sensor 3, and is therefore close to the ambient temperature around the monitored area 11. FIG.

Therefore, even if the ambient temperature fluctuates, overheating of the electrical equipment 12 can be detected accurately. Further, there is no need to use a detection means separate from the infrared array sensor 3 in order to detect variations in ambient temperature.

The infrared array sensor will detect the average temperature in each section of the monitored area. Therefore, if the overheating part of the electrical equipment is a localized area within a section, the average temperature within each section is obtained as the temperature of each section, so that such local overheating The detection sensitivity becomes dull. Alternatively, it becomes difficult to set a threshold for judging overheating.

In the prior art, when the monitoring target area covered by one infrared array sensor is narrowed to detect local overheating, more infrared array sensors are required to monitor the required area of the electrical equipment. Alternatively, if an infrared light receiving device with a large number of areas to be monitored is used to detect local overheating, the infrared array sensor becomes expensive. Also, in the prior art, increasing the total number of segments to monitor a desired area of electrical equipment requires more computing power to process the data, resulting in increased costs.

However, according to the overheat detection device 1 of Embodiment 1, the temperature rise value ΔTn of each section Gn of the monitoring target area 11 of the electrical equipment 12 is repeatedly acquired during the predetermined period for determining the threshold value K, and the maximum A threshold value K is calculated based on the temperature rise value ΔTmax of .

In this way, when an abnormal temperature rise value is detected by comparison with the threshold value K determined based on the temperature rise value ΔTn during normal operation of the electrical equipment 12 to be monitored, overheating is determined. Even moderate overheating can be properly detected. Therefore, there is no need to unnecessarily increase the number of sections in the monitored area 11, and overheating can be properly detected at low cost.

Moreover, since only one threshold value K is set for each of the plurality of categories 15, the overheat detection device 1 can be configured using a low-cost CPU 5 with low computing power. From the viewpoint of overall cost, it is desirable that the number of pixels of the infrared array sensor 3 is 100 or less.

[Embodiment 2]
Other embodiments of the invention are described below. For convenience of description, members having the same functions as those of the members described in the above embodiments are denoted by the same reference numerals, and description thereof will not be repeated.

In the overheat detection device 1 according to the first embodiment, the threshold value K is set to one value commonly for each section Gn of the monitored area 11 . In the overheat detection device 1 according to the second embodiment, threshold values Kn (n=1 to 64) are determined for each section Gn. The overheat detection device 1 according to the second embodiment is the same as the overheat detection device 1 according to the first embodiment, except that the operations of the threshold calculation process and the overheat monitoring process are different. Below, the threshold calculation process and the overheating monitoring process in the second embodiment will be described.

<Threshold calculation process>
FIG. 8 is a flowchart showing threshold calculation processing executed by the overheat detection device 1 according to the second embodiment. When the control unit 25 of the calculation unit 2 receives an instruction to execute the threshold calculation process from the external device 90 through the communication unit 4, it controls each part of the calculation unit 2 to cause the overheat detection device 1 to perform the threshold calculation process. let it start.

Step S301: When the threshold calculation process is started, the threshold calculator 24 first acquires the start time.

Step S302: Subsequently, the overheat detector 1 executes temperature rise value calculation processing. The temperature rise value calculation process is a process (subroutine) for calculating the temperature rise value ΔTn of each section Gn described using FIG. The index of the number of iterations of step S302 is denoted by i.

Step S303: Subsequently, the threshold calculator 24 determines whether or not a predetermined period of time, for example, two weeks, has passed since the start time. Here, the predetermined period is a predetermined period during which the overheat detector 1 observes the electrical equipment 12 in order to determine the threshold value Kn. If it is determined that two weeks have passed (YES in S303), the flow proceeds to step S305. Otherwise (NO in S303), the flow proceeds to step S304.

Note that the predetermined period of two weeks is an example, and the period is not limited to this. However, since the power load of the electrical equipment 12 tends to have a similar pattern for each day of the week, it is preferable to set the period for determining the threshold value Kn to one week or more.

Step S304: The threshold calculator 24 determines whether or not a predetermined period of time, for example, one hour, has passed since the most recent temperature rise value calculation process. Here, the predetermined time is a repetition cycle in which the overheat detection device 1 calculates the temperature rise value ΔTn in the threshold value calculation process. Note that the predetermined time of one hour is an example, and is not limited to this.

If it is determined that one hour has passed (YES in S304), the flow returns to step S302. This is because the overheat detection device 1 executes the temperature rise value calculation process again. Otherwise (NO in S304), the flow returns to step S303. This is because the overheat detector 1 waits until the predetermined time elapses.

Step S305: After a predetermined period of time has elapsed from the start time, the flow reaches step S305. The threshold calculator 24 calculates the maximum value among the temperature rise values ΔTn(i) repeatedly obtained for each section Gn as the maximum temperature rise value ΔTmaxn (n: 1 to 64) in each section Gn.

Step S306: Subsequently, the threshold calculator 24 calculates a threshold Kn (n: 1 to 64) for each segment Gn from the relational expression Kn=A×ΔTmaxn+B. Here, the likelihood coefficient A is a coefficient of 1 or more, and about 1 to 2 is particularly preferable. A constant B is a constant of 0 or more in consideration of temperature measurement errors in the infrared array sensor 3 . The constant B is particularly preferably about 0 to 5°C. Next, the flow of the threshold calculation process ends.

<Overheat monitoring process>
FIG. 9 is a flowchart showing overheating monitoring processing executed by the overheating detection device 1 according to the second embodiment. When the control unit 25 of the calculation unit 2 receives an instruction to execute the overheating monitoring process from the external device 90 through the communication unit 4, it controls each part of the calculation unit 2 to cause the overheating detection device 1 to perform the overheating monitoring process. let it start.

Step S401: When the overheat monitoring process is started, the overheat detector 23 determines whether or not the threshold value Kn has not yet been calculated and set. If it is determined that the threshold Kn has not been set (YES in S401), the flow proceeds to step S402. Otherwise (NO in S401), the flow proceeds to step S403.

Step S402: The overheat detection unit 23 notifies the external device 90 through the communication unit 4 that the threshold value Kn has not been set. This is because the overheat monitoring process cannot be executed if the threshold value Kn is not set. Then, the flow of the overheat monitoring process ends.

Step S403: The overheat detection device 1 executes temperature rise value calculation processing. The temperature rise value calculation process is the above-described process (subroutine) described using FIG. 6 for calculating the temperature rise value ΔTn of each section Gn.

Step S404: Subsequently, the overheat detector 23 compares the temperature rise value ΔTn (n: 1 to 64) of each section Gn with each threshold value Kn. If the temperature rise value ΔTn of each section Gn is equal to or greater than the threshold value Kn, that is, if ΔTn≧Kn is satisfied (YES in S404), the flow proceeds to step S405. Otherwise (NO in S404), the flow proceeds to step S406.

Step S405: The overheat detector 23 determines that overheating has occurred. This is because a temperature rise equal to or greater than the threshold value Kn was recognized. Flow then proceeds to step S407.

Step S406: The overheat detector 23 determines that overheating has not occurred. This is because no temperature rise exceeding the threshold value Kn was observed. Flow then proceeds to step S407.

Step S<b>407 : The overheat detection unit 23 notifies the external device 90 of the determination result through the communication unit 4 .

Step S<b>408 : Subsequently, the overheat detection unit 23 determines whether or not an instruction to stop the overheat monitoring process from the external device 90 has been received through the communication unit 4 . If it is determined that the signal has been received (YES in S408), then the flow of the overheat monitoring process ends. Otherwise (NO in S408), the flow proceeds to step S409.

Step S409: The overheat detection unit 23 determines whether a predetermined time has passed since the most recent temperature rise value calculation process. Here, the predetermined time is a monitoring interval for trying to detect overheating in the overheating monitoring process. The predetermined time can be, for example, 5 minutes.

If it is determined that the predetermined time has passed (YES in S409), the flow returns to step S403. This is because the processing after the temperature rise value calculation processing is repeated again. Otherwise (NO in S409), the flow returns to step S408. This is because the overheat detector 1 waits until the predetermined time elapses.

<Action/effect>
In the overheat detection device 1 according to the second embodiment, the threshold value Kn for determining whether the electrical equipment 12 is overheated is determined for each section Gn of the monitored area 11 . Therefore, in the overheat detection device 1 according to the second embodiment, it is possible to more appropriately determine whether or not overheating occurs compared to the case of the first embodiment.

Further, in the prior art, the degree of averaging of the temperature of the abnormal location within the section also differs depending on the size of the localized overheated location within the section. Therefore, it has been difficult to determine the temperature threshold for determining abnormal overheating. However, in this embodiment, the threshold Kn for each division can be determined mechanically, and the difficulty of threshold setting is reduced.

〔summary〕
An overheat detection device for electrical equipment according to aspect 1 of the present invention comprises an infrared array sensor that detects the temperature of a monitoring target area of the electrical equipment divided into a matrix, and acquires the temperature of each section detected by the infrared array sensor. a temperature rise value calculator for calculating the temperature rise value of each of the sections from the temperature of each of the sections; and the temperature rise value of each of the sections during a predetermined period for determining a threshold value. and a threshold calculation unit for calculating the threshold value based on the maximum value, and for obtaining the temperature rise value of each section during the monitoring period of the electrical equipment, and obtaining the temperature rise value of each section. with the threshold to detect overheating of the electrical equipment.

According to the above configuration, it is possible to realize an overheat detection device for electrical equipment that can accurately determine the occurrence of overheating even if the infrared array sensor does not sufficiently detect local overheating within the section. .

An overheat detection device for electrical equipment according to aspect 2 of the present invention comprises an infrared array sensor that detects the temperature by dividing a monitoring target area of the electrical equipment into a matrix, and acquires the temperature of each segment detected by the infrared array sensor. a temperature rise value calculator for calculating the temperature rise value of each of the sections from the temperature of each of the sections; and the temperature rise value of each of the sections during a predetermined period for determining a threshold value. and a threshold calculation unit for calculating each threshold value based on the maximum value of the temperature rise value in each of the sections; an overheat detection unit that obtains a value and compares the temperature rise value of each of the divisions with the respective threshold to detect overheating of the electrical equipment.

According to the above configuration, it is possible to realize an overheat detection device for electrical equipment that can accurately determine the occurrence of overheating even if the infrared array sensor does not sufficiently detect local overheating within the section. .

In the overheat detection device for electrical equipment according to aspect 3 of the present invention, in aspect 1 or 2 above, the threshold calculation unit multiplies the maximum value by a likelihood coefficient of 1 or more and adds a constant of 0 or more to obtain a value , and the threshold value. According to the above configuration, it is possible to appropriately set a threshold value for determining abnormal overheating of electrical equipment.

In the overheat detection device for electrical equipment according to aspect 4 of the present invention, in any one of aspects 1 to 3, the temperature rise value calculation unit uses an average value of a predetermined number of lower ranks of the temperatures in each of the categories as a reference. A configuration may be provided in which a value obtained by subtracting the reference temperature from the temperature of each section is used as the temperature rise value of each section. According to the above configuration, it is possible to appropriately calculate the temperature rise value of each section for determining abnormal overheating of the electrical equipment.

The overheat detection device for electrical equipment according to aspect 5 of the present invention may be configured such that, in any one of aspects 1 to 4, the number of the divisions for the infrared array sensor is 100 or less. According to the above configuration, it is possible to reduce the load of arithmetic processing in the overheat detection device for electrical equipment.

An overheat detection device for electrical equipment according to aspect 6 of the present invention is, in any one of aspects 1 to 5, further comprising a communication unit that notifies an external device of the occurrence of overheating in the electrical equipment. may According to the above configuration, in the overheat detection device for electrical equipment, the abnormal overheating of the electrical equipment can be notified to the external display terminal device, so remote monitoring is possible.

A method for detecting overheating of electrical equipment according to aspect 7 of the present invention divides a monitoring target area of the electrical equipment into a matrix and detects the temperature of each segment from the temperature of each segment detected by the infrared array sensor. The temperature rise value calculation substep is used as the substep of calculating the rise value, and the temperature rise value of each of the categories calculated by the temperature rise value calculation substep is repeatedly obtained for a predetermined period of time, and the maximum value thereof is used as a threshold value. and comparing the temperature rise value of each of the sections calculated by the temperature rise value calculating substep with the threshold value to detect overheating of the electrical equipment.

According to the above configuration, it is possible to realize an overheat detection device for electrical equipment that can accurately determine the occurrence of overheating even if the infrared array sensor does not sufficiently detect local overheating within the section. .

A method for detecting overheating of electrical equipment according to aspect 8 of the present invention divides a monitoring target area of electrical equipment into a matrix and detects the temperature of each segment from the temperature of each segment detected by an infrared array sensor. The temperature rise value calculation substep is used as the substep of calculating the rise value, and the temperature rise value of each of the sections calculated by the temperature rise value calculation substep is repeatedly acquired for a predetermined period of time, and the temperature rise value of each of the sections is obtained. calculating the threshold value based on the maximum value of the temperature rise value; and detecting overheating of the equipment.

According to the above configuration, it is possible to realize an overheat detection device for electrical equipment that can accurately determine the occurrence of overheating even if the infrared array sensor does not sufficiently detect local overheating within the section. .

<Additional notes>
The present invention is not limited to the above-described embodiments, but can be modified in various ways within the scope of the claims, and can be obtained by appropriately combining technical means disclosed in different embodiments. is also included in the technical scope of the present invention.

In each of the above-described embodiments, the external device 90 is a mobile terminal of an administrator or the like, and the notification from the overheat detection device 1 to the external device may be executed by means such as e-mail.

In each of the above-described embodiments, an example in which the overheat detection device 1 receives instructions from the external device 90 via the communication unit 4 and transmits the monitoring result to the external device 90 has been described. However, the overheat detection device 1 itself may be provided with an input unit that directly receives an instruction from an administrator or the like. Further, the overheat detection device 1 itself may include a reporting unit that directly reports the monitoring result or other various information to the administrator or the like. In this case, the notification unit may notify the administrator or the like of the monitoring result by means of lamp display, ringing sound, voice, or image display.

The calculation unit 2 of the overheat detection device 1 does not necessarily need to be installed in the vicinity of the electrical equipment 12 to be monitored, and may be installed remotely. In this case, the data of the temperature Tn of the infrared array sensor 3 is once logged by a device near the infrared array sensor 3, and collected by the remotely installed computing unit 2 by a method such as patrol to determine overheating. It may be a configuration that is

REFERENCE SIGNS LIST 1 overheat detection device 2 calculation unit 21 reading unit 22 temperature rise value calculation unit 23 overheat detection unit 24 threshold calculation unit 25 control unit 3 infrared array sensor 4 communication unit 5 CPU
6 non-volatile memory 7 control program 8 memory 11 monitored area 12 electrical equipment 13 busbar 14 fastening part 15 division

Claims (8)

an infrared array sensor that divides the monitored area of the electrical equipment into a matrix and detects the temperature;
a reading unit that acquires the temperature of each section detected by the infrared array sensor;
a temperature rise value calculation unit that calculates a temperature rise value of each of the sections from the temperature of each of the sections;
a threshold calculation unit that repeatedly obtains the temperature rise value of each of the sections during a predetermined period for determining a threshold, and calculates the threshold based on the maximum value thereof;
an overheat detection unit that acquires the temperature rise value of each of the sections during the monitoring period of the electrical equipment, compares the temperature rise value of each of the sections with the threshold value, and detects overheating of the electrical equipment; with
The temperature rise value calculation unit
calculating a reference temperature based on a predetermined lower number of the temperatures of the temperatures in each of the sections, and subtracting the reference temperature from the temperature of each of the sections as a temperature rise value of each of the sections; An overheat detector for electrical equipment, characterized by: an infrared array sensor that divides the monitored area of the electrical equipment into a matrix and detects the temperature;
a reading unit that acquires the temperature of each section detected by the infrared array sensor;
a temperature rise value calculation unit that calculates a temperature rise value of each of the sections from the temperature of each of the sections;
Threshold calculation for repeatedly acquiring the temperature rise value in each of the sections during a predetermined period for determining a threshold, and calculating the threshold based on the maximum value of the temperature rise in each of the sections. Department and
An overheat detection unit that acquires the temperature rise value of each of the divisions during the monitoring period of the electrical equipment, compares the temperature rise value of each of the divisions with the respective threshold values, and detects overheating of the electrical equipment. and
The temperature rise value calculation unit
calculating a reference temperature based on a predetermined lower number of the temperatures of the temperatures in each of the sections, and subtracting the reference temperature from the temperature of each of the sections as a temperature rise value of each of the sections; An overheat detector for electrical equipment, characterized by: The threshold calculator,
3. The overheat detection device for electrical equipment according to claim 1, wherein the threshold value is a value obtained by multiplying the maximum value by a likelihood coefficient of 1 or more and adding a constant of 0 or more. The temperature rise value calculation unit
4. The overheat detection device for electrical equipment according to claim 1, wherein an average value of a predetermined number of lower ranks of the temperatures in each of the sections is set as the reference temperature. 5. The overheat detector for electrical equipment according to any one of claims 1 to 4, wherein the number of said divisions for said infrared array sensor is 100 or less. 6. The overheat detection device for electrical equipment according to claim 1, further comprising a communication unit that notifies an external device of the occurrence of overheating of the electrical equipment. a temperature rise value calculation substep of calculating a temperature rise value for each of the sections based on the temperature of each section detected by an infrared array sensor that divides a monitoring target area of the electrical equipment into a matrix and detects the temperature; year,
a step of repeatedly acquiring the temperature rise value of each of the categories calculated by the temperature rise value calculating substep for a predetermined period, and calculating a threshold value based on the maximum value;
a step of comparing the temperature rise value of each of the categories calculated by the temperature rise value calculation substep with the threshold value to detect overheating of the electrical equipment ;
In the temperature rise value calculation sub-step,
calculating a reference temperature based on a predetermined lower number of the temperatures of the temperatures in each of the sections, and subtracting the reference temperature from the temperature of each of the sections as a temperature rise value of each of the sections; A method for detecting overheating in electrical equipment, characterized by: a temperature rise value calculation substep of calculating a temperature rise value for each of the sections based on the temperature of each section detected by an infrared array sensor that divides a monitoring target area of the electrical equipment into a matrix and detects the temperature; year,
Repeatedly obtaining the temperature rise value of each of the sections calculated by the temperature rise value calculation substep for a predetermined period of time, and calculating each threshold value based on the maximum value of the temperature rise value of each of the sections. a step;
a step of comparing the temperature rise value of each of the categories calculated by the temperature rise value calculation substep with the respective threshold values to detect overheating of the electrical equipment ;
In the temperature rise value calculation sub-step,
calculating a reference temperature based on a predetermined lower number of the temperatures of the temperatures in each of the sections, and subtracting the reference temperature from the temperature of each of the sections as a temperature rise value of each of the sections; A method for detecting overheating in electrical equipment, characterized by:

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