CN112557991B - Current transformer fault diagnosis method based on mole number and temperature - Google Patents
Current transformer fault diagnosis method based on mole number and temperature Download PDFInfo
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- G01R35/02—Testing or calibrating of apparatus covered by the other groups of this subclass of auxiliary devices, e.g. of instrument transformers according to prescribed transformation ratio, phase angle, or wattage rating
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- G—PHYSICS
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Abstract
The invention provides a current transformer fault diagnosis method, a device and a storage medium based on mole number and temperature, wherein the method comprises the following steps: collecting the pressure and temperature of the gas in the current transformer and calculating the mole number of the gas in the current transformer; describing the correlation of the gas mole number with the temperature according to the temperature and the gas mole number, including: drawing a scatter diagram and a correlation trend line in a two-dimensional plane space, and fitting a trend line function; and performing fault diagnosis on the current transformer based on the gas mole number and temperature dependence. According to the technical scheme provided by the invention, the current transformer is continuously monitored for 24 hours on line, the operation and fault state of the current transformer equipment can be evaluated, accidents are prevented, and a feasible means is provided for the real-time monitoring of the operation and fault state of the equipment.
Description
Technical Field
The invention relates to the technical field of fault diagnosis of current transformers, in particular to a method, a device and a storage medium for fault diagnosis of current transformers based on mole number and temperature.
Background
A large number of oil-filled electrical equipment, including transformer high-voltage bushing, current transformer, breaker and other oil-less equipment, are operated in the current power system, and in the operation process of transformer substation, the insulating state of the oil-less equipment of electric power, the running state of internal mechanism have the vital significance to the safe, steady operation of power system. However, the equipment can cause faults, explosion, fire and other serious accidents due to the reasons of manufacturing, overhauling, improper maintenance, oil quality degradation and the like, and the safe and stable operation and the power supply reliability of the power grid are affected.
At present, the maintenance of the transformer substation on the equipment generally adopts manual inspection, and a small part of the equipment can be combined with insulation on-line monitoring. The manual inspection utilizes the operator inspection and the test personnel to perform the periodic spot check. The traditional detection and analysis method comprises the steps of ultrasonic partial discharge, infrared temperature measurement, oil chromatographic analysis and the like. However, with the increasing of voltage level in recent years, the traditional offline preventive test method cannot meet the actual requirement of safe operation of modern large-scale power equipment, and is difficult to truly reflect the insulation conditions of various bushings, current transformers and other equipment under the operation condition. Since the preventive test is performed in a fixed period, the preventive test cannot be found, tracked and overhauled in time, and has a great limitation.
The traditional maintenance method mainly comprises daily detection and power failure detection. Wherein routine maintenance includes component inspection and heat generation detection; the power failure test comprises insulation resistance measurement, polarization coefficient measurement, capacitance and dielectric loss factor measurement, partial discharge measurement and inspection of transformer oil (a current transformer can take oil in a live mode).
The component inspection in daily maintenance generally detects whether oil leak, metal part corrosion prevention inspection, porcelain bushing appearance detection, ground connection condition inspection, and for the current transformer, the expansion and contraction amount of the expander is also required to be checked to determine the oil level condition. The heat generation detection is very effective for finding out the thermal defect and hot spot of the oil-less equipment, and can find out the overheat caused by the problem of poor contact of the contact point or the overhigh temperature caused by the local defect.
The insulation performance test is carried out by periodically powering off the oil-less equipment before and after operation every several years, so as to judge the insulation condition of the oil-less equipment; meanwhile, the gas content and the water content in the oil can be measured in the power failure overhaul period, and the analysis and detection of the dissolved gas in the oil are still one of the methods for diagnosing the faults of the oil-filled electrical equipment at present.
Although partial faults can be detected by the conventional method, the early diagnosis effect on the faults is poor, the effect of local discharge test performed on site is also not ideal, the current transformer cannot perform electrified oil extraction and analysis, and the chromatographic analysis data is more difficult to sample and track when abnormal data are required. Meanwhile, the periodic detection cannot prevent sudden accidents.
In the oil-less equipment such as high-voltage bushing of the transformer, current transformer, etc., the insulating oil in sealed state will decompose because of other reasons such as insulation damage, etc., and release a certain amount of gas, the insulating oil of the current transformer is a mineral oil obtained by distilling and refining natural petroleum, is a mixture composed of a plurality of hydrocarbon compounds with different molecular weights, including alkane, alkene, naphthene, aromatic hydrocarbon, etc.; when the equipment has a discharge or overheat fault, characteristic gases such as H2, CH4, C2H6, C2H4, C2H2, CO and CO2 are generated, the generated gases are dissolved in oil and released to the oil surface, and because the current transformer is of a sealing structure, the gases on the oil surface are gradually accumulated, the pressure of the gases is increased to act on liquid insulating oil, so that the oil pressure is gradually increased, the gases are accumulated for a long time, a certain air pressure is formed in a cavity, and oil injection and even explosion can be caused in severe cases. At present, the detection of characteristic gases mainly comprises two modes: and (5) oil-gas spectrum analysis and pressure monitoring. The oil chromatographic analysis generally adopts a manual sampling mode to periodically monitor the contents of acetylene, hydrogen and total hydrocarbon dissolved in the oil of the oil-less equipment, but the method has a longer period, can not find the abnormality between two detection intervals, and has potential safety hazard.
Disclosure of Invention
The invention mainly aims to provide a current transformer fault diagnosis method, device and storage medium based on correlation of molar quantity and temperature, and aims to solve the problems of gas pressure temperature monitoring and fault diagnosis in the existing current transformer.
In order to achieve the above object, the present invention provides a current transformer fault diagnosis method based on a mole number and a temperature, comprising:
Collecting the pressure and temperature of the gas in the current transformer and calculating the mole number of the gas in the current transformer;
Describing the correlation of the gas mole number with the temperature according to the temperature and the gas mole number, including: drawing a scatter diagram and a correlation trend line in a two-dimensional plane space, and fitting a trend line function; wherein the correlation between the molar quantity of the gas and the temperature comprises an alarm line, an early warning line and a trend line; the alarm line is that the number of moles of gas is equal to a preset first diagnosis threshold value; the early warning line comprises a second diagnosis threshold value with the molar quantity of the gas equal to the preset molar quantity of the gas;
And performing fault diagnosis on the current transformer based on the gas mole number and temperature dependence.
Further, the first diagnosis threshold value comprises an alarm upper limit value and an alarm lower limit value, wherein the alarm upper limit value is the preset maximum gas mole number of the current transformer, and the alarm lower limit value is the preset minimum gas mole number of the current transformer.
Further, the alarm upper limit value is 10, and the alarm lower limit value is 2.5.
Further, the second diagnosis threshold value comprises an early warning upper limit value, an early warning lower limit value, an early warning upper relation line and an early warning lower relation line; the early warning upper limit value is 8.5, and the early warning lower limit value is 3.0; wherein,
The relation formula of the early warning upper relation line is: y=0.035 x-2;
The relation of the early warning lower relation line is as follows: y=0.035 x-6.5;
Wherein y is the molar number; x is the temperature.
Further, the relationship of the trend line is:
y＝kx+b；
wherein k is a trend value; b is a constant coefficient and the molar value at a temperature of 293K is taken.
Further, the normal range of the trend value k is 0.02 to 0.05.
Further, the fault diagnosis comprises scattered distribution area diagnosis and trend line diagnosis; the scattered point distribution area diagnosis is based on an alarm area, an early warning area and a normal data area; the alarm area is an area defined by an alarm line, the early warning area is an area defined by the early warning line and the alarm line together, and the normal data area is an area defined by the early warning line; the trend line diagnosis is a diagnosis in which an actual trend line is compared with a normal allowable range.
In addition, the present invention provides a current transformer fault diagnosis device based on a mole number and a temperature, which includes a memory and a processor, wherein the memory stores a current transformer fault diagnosis program based on a mole number and a temperature that can be run on the processor, and the current transformer fault diagnosis program based on a mole number and a temperature realizes the steps of the current transformer fault diagnosis method based on a mole number and a temperature as described above when being executed by the processor.
Meanwhile, the present invention provides a storage medium, which is a computer readable storage medium, on which a current transformer fault diagnosis program based on a mole number and a temperature is stored, the current transformer fault diagnosis program based on the mole number and the temperature being executable by one or more processors to implement the steps of the current transformer fault diagnosis method based on the mole number and the temperature as described above.
The invention provides a method, a device and a storage medium for diagnosing faults of a current transformer based on mole number and temperature, which describe the correlation of the mole number of gas and the temperature according to the temperature and the mole number of gas, and comprise the following steps: the fault diagnosis of the current transformer is realized by drawing a scatter diagram and a correlation trend line in a two-dimensional plane space and fitting a trend line function, so that the current transformer is continuously monitored for 24 hours on line, the operation and fault state of the current transformer can be evaluated, accidents are prevented, and a practical means is provided for the real-time monitoring of the operation and fault state of the equipment.
Drawings
FIG. 1 is a schematic flow chart of a current transformer fault diagnosis method based on mole number and temperature according to an embodiment of the present invention;
FIG. 2 is a graph showing molar density versus temperature according to one embodiment of the present invention;
FIG. 3 is a graph showing the molar quantity versus temperature according to one embodiment of the present invention;
FIG. 4 is a schematic diagram showing the correlation diagnosis of the number of moles of gas and temperature data according to one embodiment of the present invention;
FIG. 5 is a schematic diagram of an internal structure of a fault diagnosis device for a current transformer based on mole number and temperature according to an embodiment of the present invention;
fig. 6 is a schematic diagram of a current transformer fault diagnosis program module based on mole number and temperature in a current transformer fault diagnosis device based on mole number and temperature according to an embodiment of the invention.
Detailed Description
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Referring to fig. 1, an embodiment of the present invention provides a current transformer fault diagnosis method based on a molar number and a temperature, which includes:
step S11: collecting the pressure and temperature of the gas in the current transformer and calculating the mole number of the gas in the current transformer;
step S12: describing the correlation of the gas mole number with the temperature according to the temperature and the gas mole number, including: drawing a scatter diagram and a correlation trend line in a two-dimensional plane space, and fitting a trend line function; wherein the correlation between the molar quantity of the gas and the temperature comprises an alarm line, an early warning line and a trend line; the alarm line is that the number of moles of gas is equal to a preset first diagnosis threshold value; the early warning line comprises a second diagnosis threshold value with the molar quantity of the gas equal to the preset molar quantity of the gas;
Step S13: and performing fault diagnosis on the current transformer based on the gas mole number and temperature dependence.
Specifically, the first diagnostic threshold includes an alarm upper limit value and an alarm lower limit value, where the alarm upper limit value is a preset maximum gas mole number of the current transformer, the alarm lower limit value is a preset minimum gas mole number of the current transformer, and in an embodiment, the alarm upper limit value is 10, and the alarm lower limit value is 2.5. The second diagnosis threshold value comprises an early warning upper limit value, an early warning lower limit value, an early warning upper relation line and an early warning lower relation line; the early warning upper limit value is 8.5, and the early warning lower limit value is 3.0;
Wherein,
The relation formula of the early warning upper relation line is: y=0.035 x-2;
The relation of the early warning lower relation line is as follows: y=0.035 x-6.5;
Wherein y is the molar number; x is the temperature.
The relation of the trend line is as follows:
y＝kx+b；
wherein k is a trend value; b is a constant coefficient and the molar value at a temperature of 293K is taken. Preferably, the normal range of the trend value k is 0.02 to 0.05.
The fault diagnosis comprises scattered point distribution area diagnosis and trend line diagnosis; the scattered point distribution area diagnosis is based on an alarm area, an early warning area and a normal data area; the alarm area is an area defined by an alarm line, the early warning area is an area defined by the early warning line and the alarm line together, and the normal data area is an area defined by the early warning line; the trend line diagnosis is a diagnosis in which an actual trend line is compared with a normal allowable range.
In particular, in one embodiment of the present invention, the insulating oil of the current transformer is a mineral oil obtained by distilling and refining natural petroleum, and is a mixture of hydrocarbons with different molecular weights, including alkanes, alkenes, cycloalkanes, aromatics, etc. When the equipment has a discharge or overheat fault, gases such as H2, CH4, C2H6, C2H4, C2H2, CO and CO2 are generated, the generated gases are dissolved in oil and released to the oil surface, and because the current transformer is of a sealing structure, the gases on the oil surface are gradually accumulated, the gas pressure is increased to act on the liquid insulating oil, so that the oil pressure is gradually increased, and the online monitoring of the insulation defect inside the current transformer can be realized by acquiring the change of the gas pressure.
The molar quantity of gas inside the current transformer is in a steady state equilibrium. At the same time, a certain amount of gas molecules are dissolved into the oil, and a certain amount of gas molecules are resolved from the oil and enter the upper layer of the current transformer. When the state is certain (temperature, pressure stable), the molar quantity of the gas reaches a steady state, i.e. steady state equilibrium. As the temperature increases, the solubility of the gas in the oil decreases, resulting in an increase in the number of gas molecules in the current transformer; as the temperature increases, the volume of the insulating oil expands, increasing approximately linearly. Because the load current of the equipment is relatively stable, no short-time severe change exists, the atmospheric environment temperature change is slow, and the change interval is limited, the occurrence of the equipment fault has a longer development period (hidden danger period), and the main purpose of diagnosis is to make a diagnosis conclusion within the fault development period (hidden danger period), so that the steady state can meet the requirements.
Thus, by collecting the pressure and temperature of the gas in the current transformer and calculating the number of moles of the gas in the current transformer, the correlation of the number of moles of the gas with the temperature is described according to the temperature and the number of moles of the gas, comprising: and drawing a scatter diagram and a correlation trend line in a two-dimensional plane space, and fitting a trend line function, so that fault diagnosis of the current transformer can be realized.
Specifically, the collection of the pressure and the temperature of the gas in the current transformer can be realized through an oil gas pressure sensor and a temperature sensor arranged in the current transformer, and the environment temperature of the current transformer can be approximately used. The number of gas moles in the current transformer is calculated based on the gas pressure, the gas temperature and the like in the current transformer acquired through actual acquisition by using an ideal gas state equation.
As the temperature of the oil gas increases, the solubility of the gas in the oil decreases, resulting in an increase in the number of moles (number of molecules) of the gas in the current transformer; through engineering experience data, the correlation between the molar quantity of the gas in the current transformer and the temperature can be obtained. Under normal conditions of the equipment, the correlation between the number of moles of gas in the current transformer and the measured temperature calculated by the algorithm is met or approximated, and if a large deviation occurs, the fault is considered to occur. The upward deviation is an internal abnormality generating gas failure, and the downward deviation is a low oil leakage oil failure.
Referring to fig. 2 and 3 in combination, the advantage of using the molar quantity of gas instead of the molar density for the temperature dependence study is that: as can be seen from the comparative analysis of the "molar density and temperature dependence graph" of FIG. 2 and the "molar quantity and temperature dependence graph" of FIG. 3, the correlation indexes of the two data and the fitting relation are greatly different, the correlation index of the "molar quantity and temperature dependence graph" is larger, R 2 is more than 0.9, and the gas molar quantity and temperature are better correlated, so that the temperature dependence study is carried out by adopting the gas molar quantity instead of the molar density to obtain more accurate diagnosis results.
Referring to fig. 4, the relationship fitting and deviation analysis are performed on the gas mole number and the temperature data, so as to obtain a good linear relationship between the gas mole number and the temperature. This linear relationship (trend line) represents the characteristic of the increase in the amount of released gas of the oil in the current transformer with increasing temperature. And (3) carrying out threshold judgment on the linear relation coefficient range and the original data range to obtain the state evaluation of the oil decomposition released gas in the current transformer.
Specifically, the fault diagnosis is divided into scattered point distribution area diagnosis and trend line diagnosis, as shown in fig. 4:
The scattered point distribution area diagnosis is based on the alarm area 10, the early warning area 20 and the normal data area 30; the alarm area 10 is an area defined by alarm lines, the alarm area 20 is an area defined by alarm lines and alarm lines, and the normal data area 30 is an area defined by alarm lines; the trend line diagnosis is a diagnosis in which an actual trend line is compared with the normal allowable range 40. In particular, in one embodiment of the present invention, the alarm area 10, the early warning area 20, the normal data area 30 and the trend line range 40 are as follows:
Alarm zone 10: the alarm zone 10 is an area delimited by alarm lines, the alarm lines being such that the number of moles of gas is equal to a preset first diagnostic threshold; specifically, the first diagnosis threshold includes an alarm upper limit value and an alarm lower limit value, the alarm upper limit value is a preset maximum gas mole number of the current transformer, and the alarm lower limit value is a preset minimum gas mole number of the current transformer. Specifically, in one embodiment, the alarm upper limit value is y=10, that is, the first alarm line 101; the alarm lower limit value is y=2.5, namely, the second alarm line 102, and the alarm area 10 is an area larger than the alarm upper limit value and smaller than the alarm lower limit value, namely, an area outside the first alarm line 101 and the second alarm line 102 in the figure. When the alarm upper limit value or the alarm lower limit value is exceeded, triggering the system alarm.
Early warning area 20: the early warning area is an area defined by an early warning line and an alarm line together, and the early warning line comprises a second diagnosis threshold value with the number of gas moles equal to a preset value; specifically in an embodiment, the second diagnostic threshold includes an early warning upper limit value, an early warning lower limit value, an early warning upper relationship line, and an early warning lower relationship line, where the early warning upper limit value is y=8.5, that is, the first early warning line 201; the lower warning limit value is 3.0, namely the second warning line 202. The relation formula of the early warning upper relation line is:
y＝0.035x-2；
a third warning line 203;
the relation of the early warning lower relation line is as follows:
y＝0.035x-6.5；
A fourth warning line 204;
Wherein y is the molar number; x is the temperature.
The early warning lines are formed by combining a first early warning line 201, a second early warning line 202, a third early warning line 203 and a fourth early warning line 204. The area between the warning line and the warning line is a warning area 20, where the system warning is triggered when any monitoring data falls.
Normal data area 30: the normal data area is an area defined by an early warning line; specifically, the whole area surrounded by the first warning line 201 and the third warning line 203 of the upper limit and the second warning line 202 and the fourth warning line 204 of the lower limit should be considered as normal when any monitoring data falls in the area.
Trend line range 40: the trend line diagnosis is based on the comparison of an actual trend line and a trend line in a normal range, and the relationship of the trend line is as follows:
y＝kx+b；
wherein k is a trend value; b is a constant coefficient and the molar value at a temperature of 293K is taken.
The normal range of the trend value k is 0.02-0.05.
The line of the trend line range 40, i.e. the line where the first and second trend lines 401 and 402 intersect in the figure, is the line of the trend line range, the enclosed area is the normal area 410 of the trend line, and the other area is the abnormal area 420 of the trend line.
Specifically, when fault diagnosis is carried out, the gas pressure and temperature in the current transformer are collected, the gas mole number in the current transformer is calculated, trend fitting of data is carried out by taking a period of time as a unit (for example, one week or one month), a least square method is adopted, a linear relation expression y=kx+b of fitting is made, and a condition that a correlation index R 2,R2 is more than 0.9 is reasonable is calculated, if R 2 is not more than 0.9, the data is abnormal or the fitting process is abnormal. Defining two trend line range lines as y=0.05x+b1 and y=0.02x+b2, respectively, and taking the linear relation expression y=kx+b, and taking x=293K into a y value; and then respectively bringing the x=293K and y values into y=0.05x+b1 and y=0.02x+b2 to obtain the values b1 and b2, and obtaining the expressions of the two trend line range lines. The method realizes that the three-phase data lines of the A phase, the B phase and the C phase pass through 293K (20 ℃) temperature points, and is convenient for visual imaging of diagnosis results. Further, judging the reasonable trend range, specifically:
(1) The graph observation method comprises the following steps: if the trend line of the original monitoring data falls within the range of the trend line, the monitoring data is in a normal state; when this range is exceeded, an abnormal state is obtained.
(2) Trend value diagnostic algorithm: and judging the coefficient k value in the fitted trend line relation, wherein the normal range is (0.02, 0.05), and when the coefficient k value exceeds the normal range, the coefficient k value is in an abnormal state.
The correlation (trend line) between the molar quantity of gas and the temperature is the characteristic of the state of the oil quality in the equipment, and can be kept stable for a long time under normal conditions. When the physicochemical properties of the oil inside the device change, a shift in the correlation between the molar quantity of the gas and the temperature (trend line) is caused, the shift is normal within a certain range, and when the allowable range is exceeded, an abnormality occurs in the quality of the oil.
For example: when the occurrence trend coefficient k is greater than 0.05, there is a possibility that the oil quality is severely degraded; when the occurrence trend coefficient k is smaller than 0.02, there is a possibility that the inside of the apparatus is too little or leaks.
In addition, the invention also provides a fault diagnosis device of the current transformer based on the molar quantity and the temperature.
Referring to fig. 5, an internal structure diagram of a current transformer fault diagnosis device based on mole number and temperature is provided in an embodiment of the present invention, where the current transformer fault diagnosis device based on mole number and temperature at least includes a memory 11, a processor 12, a communication bus 13 and a network interface 14.
The memory 11 includes at least one type of readable storage medium including flash memory, a hard disk, a multimedia card, a card memory (e.g., SD or DX memory, etc.), a magnetic memory, a magnetic disk, an optical disk, etc. The memory 11 may be an internal memory unit of a molar and temperature based current transformer fault diagnosis device, such as a hard disk of the molar and temperature based current transformer fault diagnosis device, in some embodiments. The memory 11 may also be an external storage device of the current transformer fault diagnosis apparatus based on the number of moles and the temperature, for example, a plug-in hard disk equipped on the current transformer fault diagnosis apparatus based on the number of moles and the temperature, a smart memory card (SMART MEDIA CARD, SMC), a Secure Digital (SD) card, a flash memory card (FLASH CARD), or the like in other embodiments. Further, the memory 11 may also include both an internal memory unit and an external memory device of the current transformer fault diagnosis apparatus based on the molar number and the temperature. The memory 11 may be used not only for storing application software installed in the current transformer fault diagnosis apparatus based on the number of moles and the temperature and various kinds of data, for example, codes of the current transformer fault diagnosis program based on the number of moles and the temperature, etc., but also for temporarily storing data that has been output or is to be output.
The processor 12 may in some embodiments be a central processing unit (Central Processing Unit, CPU), controller, microcontroller, microprocessor or other data processing chip for running program code or processing data stored in the memory 11, for example performing mole and temperature based current transformer fault diagnosis programs and the like.
The communication bus 13 is used to enable connection communication between these components.
The network interface 14 may optionally include a standard wired interface, a wireless interface (e.g., WI-FI interface), typically used to establish a communication connection between the molar-based and temperature-based current transformer fault diagnosis apparatus and other electronic devices.
Optionally, the current transformer fault diagnosis device based on the molar quantity and the temperature may further comprise a user interface, wherein the user interface may comprise a Display (play), an input unit such as a Keyboard (Keyboard), and the optional user interface may further comprise a standard wired interface and a wireless interface. Alternatively, in some embodiments, the display may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, an OLED (Organic Light-Emitting Diode) touch, or the like. The display may also be referred to as a display screen or a display unit, as appropriate, for displaying information processed in the current transformer fault diagnosis apparatus based on the number of moles and the temperature and for displaying a visual user interface.
Fig. 5 shows only a molar and temperature-based current transformer fault diagnosis apparatus having components 11-14 and a molar and temperature-based current transformer fault diagnosis program, and it will be understood by those skilled in the art that the structure shown in fig. 5 does not constitute a limitation of the molar and temperature-based current transformer fault diagnosis apparatus, and may include fewer or more components than shown, or may combine certain components, or may be a different arrangement of components.
In the embodiment of the current transformer fault diagnosis apparatus based on the number of moles and the temperature shown in fig. 5, the memory 11 stores therein a current transformer fault diagnosis program based on the number of moles and the temperature; the processor 12 performs the following steps when executing the current transformer fault diagnosis program based on the mole number and the temperature stored in the memory 11:
step S11: collecting the pressure and temperature of the gas in the current transformer and calculating the mole number of the gas in the current transformer;
step S12: describing the correlation of the gas mole number with the temperature according to the temperature and the gas mole number, including: drawing a scatter diagram and a correlation trend line in a two-dimensional plane space, and fitting a trend line function;
Step S13: and performing fault diagnosis on the current transformer based on the gas mole number and temperature dependence.
Referring to fig. 6, a schematic diagram of a program module of a current transformer fault diagnosis procedure based on mole number and temperature in an embodiment of a current transformer fault diagnosis apparatus according to the present invention is shown, where the current transformer fault diagnosis procedure based on mole number and temperature may be divided into an acquisition module 10, a calculation module 20, a setting module 30 and a diagnosis module 40, by way of example:
the acquisition module 10 is used for acquiring the pressure and the temperature of the gas in the current transformer;
A calculation module 20 for calculating the number of moles of gas in the current transformer;
A setting module 30 for setting a diagnostic threshold;
a diagnostic module 40 for current transformer fault diagnosis based on molar number and temperature.
The functions or operation steps implemented when the program modules such as the acquisition module 10, the calculation module 20, the setting module 30, and the diagnosis module 40 are executed are substantially the same as those of the above embodiment, and will not be described herein.
In addition, an embodiment of the present invention further provides a storage medium, where the storage medium is a computer readable storage medium, and a current transformer fault diagnosis program based on a molar number and a temperature is stored on the storage medium, where the current transformer fault diagnosis program based on the molar number and the temperature may be executed by one or more processors to implement the following operations:
step S11: collecting the pressure and temperature of the gas in the current transformer and calculating the mole number of the gas in the current transformer;
step S12: describing the correlation of the gas mole number with the temperature according to the temperature and the gas mole number, including: drawing a scatter diagram and a correlation trend line in a two-dimensional plane space, and fitting a trend line function;
Step S13: and performing fault diagnosis on the current transformer based on the gas mole number and temperature dependence.
The specific embodiment of the storage medium of the present invention is basically the same as the above examples of the current transformer fault diagnosis method and device based on the mole number and the temperature, and will not be described here.
Compared with the prior art, the method, the device and the storage medium for diagnosing the faults of the current transformer based on the mole number and the temperature, which are provided by the invention, describe the correlation of the mole number of the gas and the temperature according to the temperature and the mole number of the gas, and comprise the following steps: the fault diagnosis of the current transformer is realized by drawing a scatter diagram and a correlation trend line in a two-dimensional plane space and fitting a trend line function, so that the current transformer is continuously monitored for 24 hours on line, the operation and fault state of the current transformer can be evaluated, accidents are prevented, and a practical means is provided for the real-time monitoring of the operation and fault state of the equipment.
It should be noted that, the foregoing reference numerals of the embodiments of the present invention are merely for describing the embodiments, and do not represent the advantages and disadvantages of the embodiments. And the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, apparatus, article, or method that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, apparatus, article, or method. Without further limitation, an element defined by the phrase "comprising a … …" does not exclude the presence of other like elements in a process, apparatus, article or method that comprises the element.
From the above description of the embodiments, it will be clear to those skilled in the art that the above-described embodiment method may be implemented by means of software plus a necessary general hardware platform, but of course may also be implemented by means of hardware, but in many cases the former is a preferred embodiment. Based on such understanding, the technical solution of the present invention may be embodied essentially or in a part contributing to the prior art in the form of a software product stored in a storage medium (e.g. ROM/RAM, magnetic disk, optical disk) as described above, comprising instructions for causing a terminal device (which may be a drone, a mobile phone, a computer, a server, or a network device, etc.) to perform the method according to the embodiments of the present invention.
Note that the above is only a preferred embodiment of the present invention and the technical principle applied. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, while the invention has been described in connection with the above embodiments, the invention is not limited to the embodiments, but may be embodied in many other equivalent forms without departing from the spirit or scope of the invention, which is set forth in the following claims.
Claims (5)
1. The current transformer fault diagnosis method based on the molar quantity and the temperature is characterized by comprising the following steps of:
Collecting the pressure and temperature of the gas in the current transformer and calculating the mole number of the gas in the current transformer;
Describing the correlation of the gas mole number with the temperature according to the temperature and the gas mole number, including: drawing a scatter diagram and a correlation trend line in a two-dimensional plane space, and fitting a trend line function; wherein the correlation between the molar quantity of the gas and the temperature comprises an alarm line, an early warning line and a trend line; the alarm line is that the number of moles of gas is equal to a preset first diagnosis threshold value; the early warning line comprises a second diagnosis threshold value with the molar quantity of the gas equal to the preset molar quantity of the gas;
Performing fault diagnosis on the current transformer based on the correlation of the molar quantity of the gas and the temperature;
The alarm upper limit value is 10, and the alarm lower limit value is 2.5;
the second diagnosis threshold value comprises an early warning upper limit value, an early warning lower limit value, an early warning upper relation line and an early warning lower relation line; the early warning upper limit value is 8.5, and the early warning lower limit value is 3.0; wherein,
The relation formula of the early warning upper relation line is:；
the relation of the early warning lower relation line is as follows: ；
wherein y is the molar number; x is the temperature;
The relation of the trend line is as follows:
；
wherein k is a trend value; b is a constant coefficient, and a mole value at the temperature of 293K is taken;
The normal range of the trend value k is 0.02-0.05.
2. The method for diagnosing a fault in a current transformer based on a molar quantity and a temperature according to claim 1, wherein the first diagnosis threshold value includes an alarm upper limit value and an alarm lower limit value, the alarm upper limit value is a preset maximum gas molar quantity of the current transformer, and the alarm lower limit value is a preset minimum gas molar quantity of the current transformer.
3. The molar quantity and temperature based current transformer fault diagnosis method according to claim 2, wherein the fault diagnosis includes a scattered distribution area diagnosis and a trend line diagnosis; the scattered point distribution area diagnosis is based on an alarm area, an early warning area and a normal data area; the alarm area is an area defined by an alarm line, the early warning area is an area defined by the early warning line and the alarm line together, and the normal data area is an area defined by the early warning line; the trend line diagnosis is a diagnosis in which an actual trend line is compared with a normal allowable range.
4. A molar quantity and temperature based current transformer fault diagnosis device, characterized in that it comprises a memory and a processor, on which a molar quantity and temperature based current transformer fault diagnosis program is stored, which can be run on the processor, which when executed by the processor implements the steps of the molar quantity and temperature based current transformer fault diagnosis method according to any one of claims 1 to 3.
5. A storage medium, characterized in that the storage medium is a computer readable storage medium, on which a molar and temperature based current transformer fault diagnosis program is stored, which is executable by one or more processors to implement the steps of the molar and temperature based current transformer fault diagnosis method according to any one of claims 1 to 3.
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