Method for determining abnormality of power facility using temperature detection

Abstract

The present invention relates to a method for determining an abnormality of a power facility using temperature detection. The method may comprise the steps of: (a) calculating a load factor of a power facility; (b) determining an allowable temperature rise value for each load factor on the basis of the load factor; (c) determining a temperature rise measurement value of the power facility; and (d) determining that the power facility is abnormal if the temperature rise measurement value exceeds the allowable temperature rise value for each load factor.

Description

Method for Determining Abnormalities in Power Equipment Using Temperature Detection

[0001] The present invention relates to a method for determining abnormalities in power equipment using temperature detection, and more specifically, to a method for determining abnormalities in power equipment considering the load rate.

[0002] Generally, as a method to determine whether there is an abnormality in power equipment in operation, a method is used to detect the temperature of the power equipment and determine that a component that has overheated above the allowable temperature of the components of the power equipment is an abnormality of the equipment.

[0003] For example, Korean registered patent No. 10-1791305 (registered on October 23, 2017, device and method for diagnosing power equipment using a thermal imaging camera) describes a technology that uses a thermal imaging camera to photograph an area including power equipment and compares it with a judgment criterion to determine if the equipment temperature is higher than the criterion.

[0004] However, conventional temperature-based fault detection technology for power equipment has limitations in that temperature standards, such as rated allowable temperature and rated temperature rise, are set when the power equipment is operated at 100% load, and do not apply temperature standards based on the actual operating load of the power equipment.

[0005] For example, if the current load rate of the power equipment is 30% and the detected temperature is below the rated allowable temperature set based on a load rate of 100%, it is judged to be normal. However, in reality, when considering the load rate, it is an overheating abnormality, and this has the limitation that it is difficult to predict the abnormality in advance because as the load rate of the power equipment increases, the temperature rises beyond the rated allowable temperature at a very rapid rate.

[0006] The problem that the present invention aims to solve, taking into account the issues of the conventional technology described above, is to propose a variable reference temperature considering the load rate of the power equipment under monitoring, and to provide a method capable of detecting abnormalities by comparing the detected temperature of the power equipment with the variable reference temperature.

[0007] Specifically, the present invention aims to provide a method for detecting abnormalities in power equipment regardless of the load rate of the power equipment when measuring temperature, by comparing the detected temperature with the rated allowable temperature and the rated temperature rise allowable value calculated at a 100% load rate, and by comparing the detected temperature with the reference temperature to which the temperature rise allowable value for each load rate is applied. In particular, the invention aims to provide a method for detecting abnormalities in power equipment early, especially at a low load rate.

[0008] A method for determining an abnormality in power equipment using temperature detection according to a preferred embodiment of the present invention is a method for determining an abnormality in power equipment performed on a computing device, and may include: a) a step of determining a load rate of power equipment; b) a step of determining an allowable temperature rise for each load rate for said load rate; c) a step of calculating a temperature rise measurement of said power equipment; and d) a step of determining an abnormality in the power equipment when the temperature rise measurement exceeds the allowable temperature rise for each load rate.

[0009] In an embodiment of the present invention, the load rate is determined as an average load rate corresponding to a range of time differences according to a preset time constant, and further includes the step of receiving a thermal image captured at time constant intervals for the power equipment; and the temperature rise measurement value can be determined based on the thermal image.

[0010] In an embodiment of the present invention, the average load rate can be obtained as the ratio of the average load rate within the time constant range to the 100% load rate.

[0011] In an embodiment of the present invention, the allowable temperature rise for each load rate may be a value obtained by adding an allowable margin to the value obtained by multiplying the rated allowable temperature rise by the square of the average load rate.

[0012] In an embodiment of the present invention, the allowable margin may be a value set considering the error of the thermal image.

[0013] In an embodiment of the present invention, the temperature rise measurement may be a value obtained by subtracting the ambient temperature from the temperature of the power equipment.

[0014] In an embodiment of the present invention, prior to step a), a step of determining that the power equipment is abnormal if the measured temperature of the power equipment and the power equipment exceed the rated allowable temperature may be further included.

[0015] In an embodiment of the present invention, prior to step a), a step of determining that the power equipment is abnormal if the measured temperature rise exceeds the rated temperature rise allowable limit may be further included.

[0016] The method for determining abnormalities in power equipment using temperature detection according to the present invention provides a reference temperature that takes into account the load rate of the power equipment in operation, and determines whether there is an abnormality by comparing the detected temperature information with the reference temperature, thereby enabling the determination of abnormalities regardless of the load rate of the power equipment, and in particular, has the effect of detecting abnormalities in power equipment operating at a low load rate of 50% or less at an early stage.

[0017] FIG. 1 is an example diagram of the configuration of hardware that is the subject of the present invention.

[0018] Figure 2 is a flowchart of a method for determining abnormalities in power equipment using temperature detection according to the present invention.

[0019] FIG. 3 is a flowchart of a method for determining an abnormality in power equipment using temperature detection according to another embodiment of the present invention.

[0020] To fully understand the structure and effects of the present invention, preferred embodiments of the present invention are described with reference to the attached drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various forms and various modifications can be made. The description of the embodiments is provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention. In the attached drawings, components are depicted enlarged from their actual size for convenience of explanation, and the proportions of each component may be exaggerated or reduced.

[0021] Terms such as 'first' and 'second' may be used to describe various components, but said components should not be limited by said terms. These terms may be used solely for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, 'first component' may be named 'second component,' and similarly, 'second component' may be named 'first component.' Furthermore, singular expressions include plural expressions unless the context clearly indicates otherwise. Unless otherwise defined, terms used in the embodiments of the present invention may be interpreted in the sense commonly known to those skilled in the art.

[0022] The present invention relates to a method for determining abnormalities in power equipment using temperature detection, which is performed by a central processing unit (or processor) of a computing device; and in the following description, even if there is no specific mention of the entity performing the operation of the present invention, the entity performing the operation shall be the central processing unit.

[0023] Hereinafter, a method for determining an abnormality in power equipment using temperature detection according to one embodiment of the present invention will be described in detail with reference to the drawings.

[0024] FIG. 1 is an example diagram of the configuration of hardware that is the subject of the present invention, and FIG. 2 is a flowchart of a method for determining an abnormality in power equipment using temperature detection of the present invention.

[0025] Referring to FIG. 1 and FIG. 2 respectively, the present invention may include an image acquisition unit (10) for acquiring a thermal image of a power facility, a load calculation unit (20) for calculating the current load rate of the power facility, a reference calculation unit (30) for calculating an allowable temperature rise for each current load rate, and an abnormality determination unit (40) for determining whether there is an abnormality by comparing the temperature detected by the image acquisition unit (10) with the allowable temperature rise for each load rate of the reference calculation unit (30).

[0026] The load calculation unit (20), reference calculation unit (30), and abnormality determination unit (40) may be a processor of a single computing device. Additionally, although not illustrated in the drawings, the hardware acting as the subject of the present invention may further include a memory in which instructions for performing the present invention are recorded, a display for indicating an abnormality alarm, and a communication unit for notifying a user terminal of abnormality occurrence information or transmitting a shutdown signal to power equipment.

[0027] Hereinafter, the structure and operation of the present invention configured as described above will be explained in more detail.

[0028] First, in step S10, the load calculation unit (20) calculates the load rate of the current power equipment.

[0029] The load factor is a value expressed as a percentage of the current load relative to the maximum load of the power facility.

[0030] Next, in step S20, the standard calculation unit (30) calculates the allowable temperature rise for each load rate.

[0031] At this time, the allowable temperature rise for each load rate can be calculated by multiplying the allowable temperature rise for the rated temperature by the square of the current load rate (or average load rate).

[0032] The allowable rated temperature rise used in the standard calculation unit (30) is specified in the manual of the power equipment or in test results from domestic and foreign inspection agencies. Typically, for power equipment such as high-voltage switchgear, an allowable temperature rise is provided within the limit temperature and ambient temperature limits such as 40°C. At this time, the allowable temperature rise becomes the allowable rated temperature rise.

[0033] As an example of the allowable rated temperature rise, KS C IEC 62271-1 (2017) specifies that for bare-cooper or pure copper alloy contacts of high-voltage switchgear, the allowable rated temperature rise can be set to 35K at the terminal block, 75K at the non-terminal block, and 40K in oil, and can be set to 75K at silver-plated or nickel-plated terminal blocks and non-terminal blocks, and 50K in oil, etc.

[0034] This may be applied differently in connection parts that are tightened with bolts or bolt-equivalent devices.

[0035] At this time, the allowable rise in rated temperature is determined by the set time (time constant). For example, the allowable rise in rated temperature per hour can be used, and the time constant can be set differently for each component.

[0036] In particular, in calculating the load rate of step S10 of the present invention, if the calculation of the average value of the load (average load) is required, the time constant can be set differently for each component.

[0037] For example, as with the contacts described earlier, in the case of bare conductors, the time constant for temperature rise can be set to a short range of minutes to tens of minutes, and the surface temperature of the housing of an oil-filled transformer can have a time constant of about several hours due to the large amount of internal insulating oil.

[0038] This can be set according to the characteristics of each component when calculating the average load rate (the percentage of the average load within the time constant interval relative to the maximum load of the power facility).

[0039] Next, as in step S30, the abnormality judgment unit (40) compares the measured temperature rise of the equipment with the calculated allowable temperature rise for each load rate.

[0040] The temperature rise measurement at step S30 can be detected by comparing thermal images at intervals corresponding to the time constant for each component described above.

[0041] A thermal image measures the amount of infrared radiation emitted by a subject according to temperature and converts it into color temperature; generally, lower temperatures are displayed in a blue color closer to black, while higher temperatures are displayed in a red color closer to white. This is a concept of relative temperature rather than absolute temperature.

[0042] Therefore, in a specific thermal image, the temperature of the power equipment can be expressed as the value obtained by subtracting the ambient temperature from the equipment temperature, and the temperature rise measurement considering the time constant can be understood as the difference in power equipment temperatures obtained from thermal images taken at intervals of the time constant.

[0043] The actual temperature rise of the power equipment measured in this way is calculated and compared with the allowable temperature rise for each load rate of the current power equipment.

[0044] In this case, the allowable temperature rise for power equipment based on load rate may include an additional allowable margin. This takes into account the error inherent in thermal images using infrared radiation. For example, an error of approximately 5K may occur, and this can be applied variably considering the performance of the thermal imaging camera.

[0045] Next, if the temperature rise measurement resulting from the judgment in step S30 exceeds the allowable temperature rise limit for each load rate, it is determined to be an abnormality in the power equipment as in step S40; if it does not exceed the limit, it can be determined that the power equipment is normal as in step S50.

[0046] Through this process, the present invention verifies whether there is an abnormality in the equipment by comparing the temperature rise measurement based on the variable temperature rise allowable value according to the current load rate of the power equipment, thereby enabling verification of whether there is an abnormality in the power equipment operating at a load rate other than 100%.

[0047] FIG. 3 is a flowchart of a method for determining an abnormality in power equipment using temperature detection according to another embodiment of the present invention.

[0048] Referring to FIG. 3, the present invention may include a step (S100) of determining that the power equipment is faulty if the temperature measurement of the power equipment measured in a thermal image exceeds the rated allowable temperature for each piece of equipment, a step (S200) of determining that the power equipment is faulty if the temperature measurement is below the rated allowable temperature for each piece of equipment and the temperature rise measurement exceeds the rated allowable temperature rise, and a step (S300) of determining that the power equipment is faulty if the temperature rise measurement is below the rated allowable temperature rise and the temperature rise measurement exceeds the temperature rise allowable standard for each load rate.

[0049] The above S300 step is to be identical to the configuration and operation described in detail above with reference to FIG. 2.

[0050] In step S100, the temperature measurement value, which is the result of detecting the temperature of the power equipment (or component) among the thermal images at the current time detected by the image acquisition unit (10), can be determined by simply comparing it with the rated allowable temperature presented in the manual of the power equipment.

[0051] At this time, the rated allowable temperature is considered to be the maximum allowable temperature when the load rate of the power equipment is 100%.

[0052] In the S100 stage, since the time constant is not considered and the measured value is simply compared with the reference value, there is an advantage in that the determination of whether an anomaly exists can be made very quickly.

[0053] However, it is insufficient to make an accurate judgment because it is affected by the performance of the image acquisition unit (10) that detects the thermal image.

[0054] If the temperature measurement exceeds the rated allowable temperature, it is determined to be abnormal; if the temperature measurement is below the rated allowable temperature, it is initially confirmed to be normal, and then step S200 is performed.

[0055] The S200 step compares the temperature rise measurement considering the time constant with the allowable rated temperature rise at a load rate of 100%.

[0056] In this case, the temperature of the power equipment in a specific thermal image can be expressed as the value obtained by subtracting the ambient temperature from the temperature of the equipment, and the temperature rise measurement considering the time constant can be understood as the difference in the temperature of the power equipment obtained from thermal images taken at intervals of the time constant.

[0057] The actual temperature rise of the power equipment measured in this way is calculated and compared with the current allowable rated temperature rise of the power equipment.

[0058] As previously explained, the allowable rated temperature rise is the maximum allowable temperature rise within a specific time constant range set in the manual, etc., and does not take into account the allowable margin explained previously, and assumes a load rate of 100%.

[0059] If the measured temperature rise of the power equipment at this time exceeds the allowable rated temperature rise of the power equipment, it is determined to be an equipment malfunction.

[0060] In step S200, if the measured temperature rise is below the allowable rated temperature rise limit of the power equipment, it is determined to be normal, and step S300 is performed.

[0061] Step S300 is the same process as the process described earlier with reference to FIG. 2, and the reference calculation unit (30) calculates the allowable temperature rise for each load rate (Step S20 of FIG. 2).

[0062] At this time, the allowable temperature rise for each load rate can be calculated by multiplying the allowable temperature rise of the S200 stage by the square of the current load rate (or average load rate).

[0063] The allowable rated temperature rise is specified in the manuals of power equipment or in test results from domestic and international inspection agencies. Typically, for power equipment such as high-voltage switchgear, an allowable temperature rise is provided within the limit temperature and ambient temperature limits, such as 40°C. In this case, the allowable temperature rise becomes the allowable rated temperature rise.

[0064] In this way, the present invention can determine whether the current power facility is functioning normally by comparing the temperature rise measurement with the allowable temperature rise for each load rate.

[0065] Therefore, since the S100 and S200 stages use the rated allowable temperature and rated allowable temperature rise at 100% load rate, respectively, even if the current temperature or temperature rise is judged to be normal, it may be judged to be an abnormality of the power equipment in the S300 stage.

[0066] Specific examples of cases where an abnormality in power equipment is determined only at the S300 stage are explained below.

[0067] The following example concerns temperature measurement and abnormality determination for the spring contacts of a power fuse.

[0068] Assume that the measured contact temperature of the fuse is 58°C, the ambient temperature is 30°C, and the average load rate of the power equipment is 50%. In this case, the rated allowable temperature of the fuse contact according to the standard is 75°C, and the rated allowable temperature rise is 35K. The rated allowable temperature rise, which represents the temperature difference, is expressed in absolute temperature K.

[0069] First, when comparing the measured temperature and the rated allowable temperature as in step S100, it is determined to be normal because the measured temperature is 58℃ and the rated allowable temperature is 75℃.

[0070] Next, in step S200, the temperature rise is measured, which is 28K (the temperature difference is expressed in absolute temperature) by subtracting the ambient temperature of 30℃ from the measured temperature of 58℃. When this is compared to the rated allowable temperature rise of 35K, the temperature rise of the power equipment is determined to be normal.

[0071] In the S300 stage, the temperature rise measurement of 28K is compared with the allowable temperature rise for each load rate.

[0072] The allowable temperature rise for each load rate is calculated based on the rated allowable temperature rise (35K) and the load rate (50%) at the time of current measurement. The formula can be expressed as the following mathematical formula 1.

[0073] [Mathematical Formula 1]

[0074] Allowable temperature rise per load rate = 35K x (50% / 100%) 2 = 8.75K

[0075] At this time, if the allowable margin (5K) is applied, the final temperature rise per load rate becomes 13.75K.

[0076] In other words, the previously measured temperature rise value of 28K is greater than the final temperature rise value of 13.75K per load rate, so it is judged to be abnormal.

[0077] As such, the present invention provides a temperature standard based on the actual operating load rate of power equipment, and by comparing the temperature results detected according to the temperature standard, it is possible to make a more accurate determination of abnormality or normality.

[0078] In addition, it is possible to determine whether the power equipment is normal or abnormal even below the rated allowable temperature, which is the maximum allowable temperature of the power equipment, and it has the feature of enabling faster determination.

[0079]

[0080] Although embodiments according to the present invention have been described above, they are merely illustrative and those skilled in the art will understand that various modifications and equivalent embodiments are possible therefrom. Accordingly, the true technical scope of protection of the present invention should be determined by the following claims.

Claims

1. A method for determining abnormalities in power equipment performed on a computing device, a) A step for determining the load factor of power facilities; b) A step of determining an allowable temperature rise for each load rate based on the above load rate; c) a step of determining the temperature rise measurement of the above power equipment; and d) A method for determining an abnormality in power equipment, comprising the step of determining an abnormality in power equipment when the above temperature rise measurement exceeds the allowable temperature rise limit for each load rate.

2. In Paragraph 1, The above load rate is determined as an average load rate corresponding to the range of time differences based on a preset time constant, and The method further includes the step of receiving thermal images of the power equipment taken at time constant intervals; A method for determining abnormalities in power equipment, characterized in that the above temperature rise measurement is determined based on the above thermal image.

3. In Paragraph 2, The above average load rate is, A method for determining abnormalities in power equipment, characterized by being obtained as the ratio of the average load rate within a time constant range to a 100% load rate.

4. In Paragraph 2, The above allowable temperature rise for each load rate is, A method for determining abnormalities in power equipment, characterized by adding an allowable margin to the value obtained by multiplying the rated temperature rise allowable value by the square of the average load rate.

5. In Paragraph 4, The allowable margin is, A method for determining abnormalities in power equipment, characterized by a value set considering the error of a thermal image.

6. In Paragraph 1, The above temperature rise measurement is, A method for determining abnormalities in power equipment, characterized by being a value obtained by subtracting the ambient temperature from the temperature of the power equipment.

7. In Paragraph 1, Prior to step a) above, A method for determining an abnormality in power equipment, further comprising a step of determining an abnormality in power equipment if the measured temperature of the power equipment and the power equipment exceed the rated allowable temperature.

8. In Paragraph 1, Prior to step a) above, A method for determining abnormalities in power equipment, further comprising a step of determining that the power equipment is abnormal if the measured temperature rise exceeds the rated temperature rise allowable limit.

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