A method and device for detecting internal faults of an insulating oil-filled power equipment

Abstract

The application discloses an internal fault detection method and device for insulating oil filled power equipment, and relates to the technical field of power equipment state monitoring. The volume percentage of each characteristic gas in the total characteristic gas in an insulating oil sample is calculated; two characteristic gases are selected from three characteristic gases as a first gas and a second gas, and a rectangular coordinate system with the volume percentage of the first gas as a horizontal axis variable and the volume percentage of the second gas as a vertical axis variable is constructed; a target area in the rectangular coordinate system is determined as a fault diagnosis space; according to a fault classification rule, the target area is divided into a plurality of non-overlapping fault areas; the volume percentage of the first gas is taken as a horizontal coordinate, the volume percentage of the second gas is taken as a vertical coordinate, and a target coordinate point is obtained; and the target fault type is determined according to the fault area where the target coordinate point is located. In this way, the detection efficiency is improved while ensuring the detection accuracy.

Description

Technical Field

[0001] This application relates to the field of power equipment condition monitoring technology, and in particular to a method and device for detecting internal faults in power equipment filled with insulating oil. Background Technology

[0002] Transformers and other power equipment typically use insulating oil as a cooling and insulating medium. When overheating or discharge faults occur inside the equipment, the insulating oil will decompose under high temperature or electric field conditions, producing hydrogen gas. ), methane ( ), ethane ( ), ethylene ) and acetylene ( Characteristic gases such as those dissolved in insulating oil can be analyzed to effectively diagnose the type and severity of internal equipment faults. This method is called DGA (Dissolved Gas Analysis).

[0003] In related technologies, the International Electrotechnical Commission standard IEC 60599 (Mineral oil-filled electrical equipment in service - Guidance on the interpretation of dissolved and freegases analysis) recommends various DGA diagnostic methods. Among them, the Duval equilateral triangle method is widely used due to its intuitiveness and accuracy. This method uses an equilateral triangle coordinate system to... , as well as The volume percentages of the three gases are used as three coordinate axes to divide the interior of the triangle into multiple fault regions.

[0004] However, determining the fault area based on the Duval equilateral triangle method may have the following problems: the visualization of fault points requires complex trigonometric function calculations and coordinate projection transformations, resulting in complex software logic; and embedded implementation requires additional hardware resources, leading to high hardware implementation costs. Summary of the Invention

[0005] In view of this, this application provides a method and apparatus for detecting internal faults in power equipment filled with insulating oil, which improves detection efficiency while ensuring detection accuracy.

[0006] The objective of this application can be achieved through the following technical solutions:

[0007] The first aspect of this application is to provide a method for detecting internal faults in insulating oil-filled power equipment, including:

[0008] Obtain insulating oil samples from insulating oil-filled power equipment in operation;

[0009] The volume concentrations of three characteristic gases in an insulating oil sample were detected.

[0010] The volume concentration of the characteristic gases is normalized to obtain the volume percentage of each characteristic gas in the total characteristic gases.

[0011] Two characteristic gases are selected from the three characteristic gases, namely the first gas and the second gas, and a rectangular coordinate system is constructed with the volume percentage of the first gas as the horizontal axis variable and the volume percentage of the second gas as the vertical axis variable.

[0012] The target area in the rectangular coordinate system is defined as the fault diagnosis space. The target area is an isosceles right triangle: the origin of the coordinate system is the right-angle vertex of the isosceles right triangle, the right horizontal axis is the first right-angled side, the upper vertical axis is the second right-angled side, and the length of the first right-angled side and the second right-angled side are both 100.

[0013] According to the fault classification rules, the target area is divided into multiple non-overlapping fault areas, where each fault area corresponds to a fault type.

[0014] The target coordinate point is obtained by plotting the volume percentage of the first gas on the x-axis and the volume percentage of the second gas on the y-axis.

[0015] Determine the type of target fault based on the fault area where the target coordinate point is located;

[0016] Output the target fault type.

[0017] In one alternative embodiment, different preset fault classification rules apply to different types of insulating oil-filled electrical equipment.

[0018] In one optional embodiment, the three characteristic gases include a first gas, a second gas, and a third gas. The volume concentrations of the characteristic gases are normalized to obtain the volume percentage of each characteristic gas in the total characteristic gases, including:

[0019] The volume concentrations of the first gas and the second gas are normalized to obtain the volume percentages of the first gas and the second gas in the total characteristic gas.

[0020] The volume percentage of the third gas in the total characteristic gas is calculated based on the following formula:

[0021] ;

[0022] in, This indicates the volume percentage of the third gas in the total characteristic gas. This indicates the volume percentage of the first gas in the total characteristic gas. This indicates the volume percentage of the second gas in the total characteristic gas.

[0023] In one alternative embodiment, the fault classification rules are determined by the IEC 60599 standard using the Duval equilateral triangle graphical tool.

[0024] In one optional embodiment, the target area is divided into multiple non-overlapping fault areas according to fault classification rules, including:

[0025] Based on the IEC 60599 standard, obtain the gas volume percentage thresholds corresponding to different fault types;

[0026] The gas volume percentage threshold is converted into a linear boundary corresponding to the fault type.

[0027] The target area is divided into multiple non-overlapping fault regions based on the linear boundaries.

[0028] In an optional embodiment, when the three characteristic gases are acetylene, ethylene, and methane, the fault region includes a partial discharge PD region, a low-temperature fault T1 region, a medium-temperature fault T2 region, a high-temperature fault T3 region, a low-energy discharge D1 region, a high-energy discharge D2 region, and a mixed fault DT region. The high-energy discharge D2 region includes a first high-energy electron discharge region and a second high-energy electron discharge region, and the mixed fault DT region includes a first mixed fault sub-region, a second mixed fault sub-region, and a third mixed fault sub-region.

[0029] The range of the partial discharge (PD) region is such that the sum of the volume percentages of acetylene and ethylene is not greater than 2.

[0030] The range of the low-temperature fault T1 region is: the volume percentage of acetylene is not greater than 4%, the volume percentage of ethylene is not greater than 20%, and the sum of the volume percentages of acetylene and ethylene is greater than 2.

[0031] The area range of the T2 region of the intermediate heat fault is: the volume percentage of acetylene is not greater than 4%, and the volume percentage of ethylene is not less than 20% and not greater than 50%.

[0032] The area range of the high-temperature fault T3 region is: the volume percentage of acetylene is not greater than 15%, the volume percentage of ethylene is greater than 50%, and the sum of the volume percentages of acetylene and ethylene is not greater than 100%.

[0033] The range of the low-energy discharge D1 region is: the volume percentage of acetylene is greater than 13%, the volume percentage of ethylene is not greater than 23%, and the sum of the volume percentages of acetylene and ethylene is not greater than 100%.

[0034] The first high-energy electron discharge region is defined as follows: the volume percentage of acetylene is greater than 13 and not greater than 29, and the volume percentage of ethylene is greater than 23 and not greater than 40.

[0035] The second high-energy electron discharge region is defined as follows: the volume percentage of acetylene is greater than 29%, the volume percentage of ethylene is greater than 23%, and the sum of the volume percentages of acetylene and ethylene is not greater than 100%.

[0036] The first mixed fault sub-region is defined as follows: the volume percentage of acetylene is greater than 4 and not greater than 13, and the volume percentage of ethylene is not greater than 40%.

[0037] The second mixed fault sub-region is defined as follows: the volume percentage of acetylene is greater than 4 and not greater than 29, and the volume percentage of ethylene is not less than 40 and not greater than 50.

[0038] The third mixed fault sub-region is defined as follows: the volume percentage of acetylene is greater than 15% and not greater than 29%, the volume percentage of ethylene is greater than 50%, and the sum of the volume percentages of acetylene and ethylene is not greater than 100%.

[0039] The second aspect of this application is to provide an internal fault detection device for insulating oil-filled power equipment, comprising:

[0040] The first acquisition module is used to acquire insulating oil samples of insulating oil-filled power equipment in operation.

[0041] The detection module is used to detect the volume concentration of three characteristic gases in the insulating oil sample;

[0042] The normalization module is used to normalize the volume concentration of the characteristic gases to obtain the volume percentage of each characteristic gas in the total characteristic gases.

[0043] The module is used to select two characteristic gases from three characteristic gases, namely the first gas and the second gas, and to construct a rectangular coordinate system with the volume percentage of the first gas as the horizontal axis variable and the volume percentage of the second gas as the vertical axis variable.

[0044] The first determining module is used to determine the target area in the rectangular coordinate system as the fault diagnosis space. The target area is an isosceles right triangle: the origin of the coordinate system is the right-angle vertex of the isosceles right triangle, the right horizontal half-axis is the first right-angle side, the upper vertical half-axis is the second right-angle side, and the length of the first right-angle side and the second right-angle side is 100.

[0045] The partitioning module is used to divide the target area into multiple non-overlapping fault regions according to the fault classification rules, where each fault region corresponds to a fault type.

[0046] The second acquisition module is used to obtain the target coordinate point by using the volume percentage of the first gas as the horizontal axis and the volume percentage of the second gas as the vertical axis.

[0047] The second determination module is used to determine the type of target fault based on the fault area where the target coordinate point is located.

[0048] The output module is used to output the target fault type.

[0049] A third aspect of this application is to provide an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method of the first aspect.

[0050] A fourth aspect of this application is to provide a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the method of the first aspect.

[0051] Compared with existing technologies, the method for detecting internal faults in insulating oil-filled power equipment provided in this application calculates the volume percentage of each characteristic gas in the total characteristic gas in the insulating oil sample; selects two characteristic gases from three types, designated as the first gas and the second gas respectively, and constructs a rectangular coordinate system with the volume percentage of the first gas as the horizontal axis variable and the volume percentage of the second gas as the vertical axis variable; defines the target area in the rectangular coordinate system as the fault diagnosis space; divides the target area into multiple non-overlapping fault areas according to fault classification rules; obtains the target coordinate point with the volume percentage of the first gas as the horizontal axis and the volume percentage of the second gas as the vertical axis; and determines the target fault type based on the fault area where the target coordinate point is located. This approach improves detection efficiency while ensuring detection accuracy. Attached Figure Description

[0052] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0053] Figure 1 A schematic diagram of a fault region determined by the Duval equilateral triangle method in related technologies;

[0054] Figure 2A schematic diagram illustrating the establishment of a rectangular coordinate system based on the Duval equilateral triangle provided in related technologies;

[0055] Figure 3 A flowchart illustrating an internal fault detection method for insulating oil-filled power equipment provided in this application embodiment;

[0056] Figure 4 This is a schematic diagram illustrating how a target area is divided into multiple non-overlapping fault areas according to fault classification rules, as provided in an embodiment of this application.

[0057] Figure 5 A structural block diagram of an insulating oil-filled internal fault detection device for power equipment provided in this application embodiment;

[0058] Figure 6 This is a structural block diagram of an electronic device for implementing a method for detecting internal faults in power equipment filled with insulating oil, as provided in an embodiment of this application. Detailed Implementation

[0059] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present application.

[0060] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0061] It should be understood that in the embodiments of this application, "at least one" means one or more, and "more than one" means two or more. "And / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. The character " / " generally indicates that the related objects before and after it are in an "or" relationship. "Contains A, B and / or C" means containing any one, two, or three of A, B, and C.

[0062] It should be understood that in the embodiments of this application, "B corresponding to A", "B corresponding to A", "A corresponds to B", or "B corresponds to A" means that B is associated with A, and B can be determined based on A. Determining B based on A does not mean that B is determined solely based on A; B can also be determined based on A and / or other information.

[0063] To address the technical problems existing in related technologies, this application provides a method and apparatus for detecting internal faults in power equipment filled with insulating oil.

[0064] The method for detecting internal faults in insulating oil-filled power equipment provided in this application can be executed by an electronic device, such as a terminal or a server. The terminal can be a smartphone, tablet, laptop, or other similar device. The server can be a standalone physical server, a server cluster or distributed system composed of multiple physical servers, or a cloud server providing basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud storage, network services, cloud communication, middleware services, domain name services, security services, CDN (Content Delivery Network), and big data and artificial intelligence platforms. It is understood that this application does not limit the specific entity executing the method for detecting internal faults in insulating oil-filled power equipment.

[0065] The technical solution of this application will be described in detail below through specific embodiments. It should be noted that the following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments described below are used to explain the technical solution of this application and are not intended to limit actual use.

[0066] Figure 1 This is a schematic diagram of a fault region determined based on the Duval equilateral triangle method in related technologies. Figure 1In the diagram, the left slant side represents the volume percentage of methane, from bottom to top: 0, 20, 40, 60, 80, and 100. The right slant side represents the volume percentage of ethylene, from top to bottom: 0, 20, 40, 60, 80, and 100. The bottom horizontal line represents the volume percentage of acetylene, from right to left: 0, 20, 40, 60, 80, and 100. The arrows indicate the direction in which the volume percentage of each gas increases. Figure 1 The system is divided into multiple zones, each representing a different type of fault. Figure 1 The fault types include partial discharge (PD), low-energy discharge (D1), high-energy discharge (D2), mixed fault (DT), low-temperature fault (T1), medium-temperature fault (T2), and high-temperature fault (T3). However, determining the fault region based on the Duval equilateral triangle method has the following problems:

[0067] First, visualizing the fault point is complex. There are multiple methods to calculate the specific location of fault point 'a' within the Duval equilateral triangle. One simple implementation involves establishing a Cartesian coordinate system on top of the equilateral triangle coordinate system, such as... Figure 2 As shown, in this rectangular coordinate system, the coordinates of fault point a are (X, Y), and the coordinates of the vertices of the Duval equilateral triangle are A(0, 0), B(100, 0), C(50, 0), and D(100, 0). The coefficient A is obtained based on the vertex coordinates. x =0, A y =0, B x =100, B y =0, C x =50, C y = Then, use the following formulas to calculate X and Y:

[0068] (1)

[0069] (2)

[0070] in, This indicates the volume percentage of acetylene. This indicates the volume percentage of ethylene. This indicates the volume percentage of methane.

[0071] For example, =18、 =47 and Substituting 35 into the above formula, we get X = 64.5 and Y = 30.3. That is, point a has two coordinates: in the Duval equilateral triangle, the coordinates of point a are (18, 47, 35); in the rectangular coordinate system created for visualization, the coordinates of point a are (64.5, 30.3). However, in the isosceles rectangular triangle coordinate system of this application, the coordinates of point a are... and The value is a(18, 47), so there is no need to create a Cartesian coordinate system for visualization.

[0072] It's easy to understand that in the Duval equilateral triangle, the three coordinate axes are evenly distributed at 60°. Visualizing fault points requires complex trigonometric function calculations and coordinate projection transformations, leading to complex software logic. Moreover, embedded implementation requires additional hardware resources, resulting in high hardware implementation costs.

[0073] Furthermore, the Duval equilateral triangle uses three coordinate axes that are 60° apart, which is completely different from the rectangular coordinate system commonly used by engineers. The logic of the coordinate data extension direction is abnormal; the 0 point of each coordinate axis corresponds to the maximum point of another coordinate axis, which does not conform to the conventional understanding of "increasing from the origin". The meaning of the coordinates is not intuitive, and this coordinate system increases the difficulty of learning.

[0074] Furthermore, engineers need to simultaneously locate the fault along three oblique coordinate axes distributed at 60° angles, especially near the boundary of the fault area. Accurate interpretation requires a strong sense of spatial awareness and experience, and the unusual coordinate axis orientation can easily lead to visual biases and misjudgments. For example, when =18, When =47, the fault point is Figure 3 The intersection point 'a' of the two diagonal dashed lines is located in the DT zone, indicating that the fault type is DT, but it is visually easy to misjudge as T3.

[0075] Furthermore, while only two of the three gas volume percentages are independent variables, the third variable can be uniquely determined by a linear relationship (i.e., the sum of the three variables is always equal to 100). However, the Duval equilateral triangle still uses three axes to represent the volume percentages of the three gases, forcing engineering applications to process three coordinate information simultaneously. This redundant variable complicates the diagnostic logic. For example, Figure 2 middle, =100-47-18=35, corresponding to Figure 2 The horizontal dashed line in the image is not actually needed.

[0076] To address the technical problems existing in related technologies, this application provides a method for detecting internal faults in insulating oil-filled power equipment, such as... Figure 3 As shown, Figure 3This is a flowchart illustrating a method for detecting internal faults in insulating oil-filled power equipment, as provided in an embodiment of this application. It should be noted that the steps shown may be executed in a logical order different from that shown in the flowchart. The method may include the following steps S301 to S309.

[0077] Step S301: Obtain an insulating oil sample from the insulating oil-filled power equipment in operation.

[0078] In one alternative embodiment, a fully sealed glass syringe method is used to collect insulating oil samples from the sampling valve of the equipment while the equipment is in operation.

[0079] Step S302: Detect the volume concentration of three characteristic gases in the insulating oil sample.

[0080] In one optional embodiment, dissolved gases in the oil are extracted using an automated headspace or mechanical vibration method; gas chromatographs are used to separate and quantify the gas components, and the volume concentration is calculated; the volume concentration is then output.

[0081] Step S303: Normalize the volume concentration of the characteristic gases to obtain the volume percentage of each characteristic gas in the total characteristic gases.

[0082] In one optional embodiment, the three characteristic gases include a first gas, a second gas, and a third gas. The volume concentrations of the characteristic gases are normalized to obtain the volume percentage of each characteristic gas in the total characteristic gases, including:

[0083] The volume concentrations of the first gas and the second gas are normalized to obtain the volume percentages of the first gas and the second gas in the total characteristic gas.

[0084] The volume percentage of the third gas in the total characteristic gas is calculated based on the following formula:

[0085] (3)

[0086] in, This indicates the volume percentage of the third gas in the total characteristic gas. This indicates the volume percentage of the first gas in the total characteristic gas. This indicates the volume percentage of the second gas in the total characteristic gas.

[0087] In one alternative embodiment, the characteristic gas may be acetylene, ethylene, and methane.

[0088] In one specific embodiment, the volume concentrations of the first gas and the second gas are normalized to obtain the volume percentages of the first gas and the second gas in the total characteristic gas, including:

[0089] When the first or second gas is acetylene, the volume percentage of acetylene is calculated using the following formula:

[0090] (4)

[0091] in, This indicates the volume percentage of acetylene. This represents the volume concentration of acetylene. This represents the volume concentration of ethylene. This represents the volume concentration of methane.

[0092] When the first or second gas is ethylene, the volume percentage of ethylene is calculated using the following formula:

[0093] (5)

[0094] in, This indicates the volume percentage of ethylene.

[0095] When the first or second gas is methane, the volume percentage of methane is calculated using the following formula:

[0096] (6)

[0097] in, This indicates the volume percentage of methane.

[0098] First, based on the determined first and second gases, calculate the volume percentage of the first and second gases using formulas (4), (5) or (6), and then calculate the volume percentage of the third gas using formula (3).

[0099] Step S304: Select two characteristic gases from the three characteristic gases, and use them as the first gas and the second gas respectively. Construct a rectangular coordinate system with the volume percentage of the first gas as the horizontal axis variable and the volume percentage of the second gas as the vertical axis variable.

[0100] Step S305: Determine the target area in the rectangular coordinate system as the fault diagnosis space.

[0101] It should be noted that the target region in the rectangular coordinate system is defined as the fault diagnosis space, and the target region is an isosceles right triangle: the origin of the coordinate system is the right-angle vertex of the isosceles right triangle, the right horizontal axis is the first leg, and the upper vertical axis is the second leg, with the length of both the first and second legs being 100. That is, the set of points falling within this target region satisfies x≥0, y≥0, and x+y≤100.

[0102] Step S306: Divide the target area into multiple non-overlapping fault areas according to the fault classification rules.

[0103] It should be noted that the default fault classification rules are determined by the IEC 60599 standard using the Duval equilateral triangle.

[0104] In one optional embodiment, the target area is divided into multiple non-overlapping fault areas according to fault classification rules, specifically including the following steps:

[0105] Based on the IEC 60599 standard, the volume percentage threshold of gas corresponding to different fault types is obtained; the volume percentage threshold of gas is converted into linear boundaries corresponding to the fault types; and the target area is divided into multiple non-overlapping fault areas according to the linear boundaries.

[0106] It should be noted that each fault area corresponds to a fault type.

[0107] In one alternative embodiment, different preset fault classification rules apply to different types of insulating oil-filled electrical equipment.

[0108] In one specific embodiment, Figure 4 This embodiment of the application provides a schematic diagram of dividing a target area into multiple non-overlapping fault areas according to fault classification rules, specifically including the following steps:

[0109] Step 1: Obtain the gas volume percentage thresholds corresponding to different fault types based on the IEC 60599 standard:

[0110] In one specific embodiment, : 4, 13, 15 and 29; : 20, 23, 40, and 50; :98.

[0111] Step 2: Convert the gas volume percentage threshold into a linear boundary corresponding to the fault type:

[0112] In one specific embodiment, the linear boundaries for acetylene are: x=4, x=13, x=15 and x=29; the linear boundaries for ethylene are: y=20, y=23, y=40 and y=50; and the linear boundary for methane is: x+y=2.

[0113] Step 3: Divide the target area into multiple non-overlapping fault regions based on the linear boundaries, as shown in Table 1. Specifically, this includes the x (horizontal coordinate) range, the y (vertical coordinate) range, and the x+y (sum of the horizontal and vertical coordinates) range:

[0114] Table 1

[0115]

[0116] It should be noted that the above inequalities define the fault region, such as... Figure 4 As shown, these represent the following regions: low-energy discharge (D1), high-energy discharge (D2), mixed fault (DT), partial discharge (PD), low-temperature fault (T1), medium-temperature fault (T2), and high-temperature fault (T3). PD, T1, T2, T3, D1, D2, and DT are internationally recognized fault type codes, derived from the IEC 60599 standard and the Duval equilateral triangle method. These are not arbitrary abbreviations but rather a scientific classification of internal insulation faults with different energy levels and physical mechanisms.

[0117] contrast Figure 1 and Figure 4 It can be seen that the judgment criteria of the isosceles right triangle fault diagnosis space are equivalent to those of the Duval equilateral triangle fault diagnosis space, but the isosceles right triangle fault diagnosis space is more intuitive, has a lower misjudgment rate, and is easier to use.

[0118] Step S307: Using the volume percentage of the first gas as the abscissa and the volume percentage of the second gas as the ordinate, obtain the target coordinate point.

[0119] Step S308: Determine the target fault type based on the fault area where the target coordinate point is located.

[0120] In one alternative embodiment, the target coordinate point is mapped to the target area, and the target fault type is determined based on the fault area where the target coordinate point is located.

[0121] In one specific embodiment, if the target coordinate point falls into the partial discharge PD region, it is determined to be a partial discharge;

[0122] If the target coordinate point falls into the low-energy discharge D1 region / high-energy discharge D2 region, it is determined to be a low-energy / high-energy discharge; if the target coordinate point falls into the low-thermal fault T1 region / medium-thermal fault T2 region / high-thermal fault T3 region, it is determined to be a thermal fault of different temperature levels; if the target coordinate point falls into the mixed fault DT region, it is determined to be a mixed fault.

[0123] Step S309: Output the target fault type.

[0124] The output target fault type is used for equipment operation status analysis, status monitoring, and operation and maintenance auxiliary decision-making.

[0125] In this embodiment, it is compatible with existing standards: all area limits are completely consistent with the IEC 60599 standard, only the coordinate representation is changed, and the consistency of diagnostic results reaches 100%, without changing the existing operation and maintenance cognitive system of the industry; it is easy to operate: the rectangular coordinates are intuitive and easy to read; it is easy to implement in engineering: embedded devices no longer need complex trigonometric functions and projection calculations, only comparison operations are required, which makes it convenient for developers to write code for fault diagnosis, the judgment response time is less than 50ms, and the hardware cost is reduced by 60%.

[0126] Furthermore, through the verification of collected sample data, the internal fault detection method for insulating oil-filled power equipment provided in this application embodiment effectively improves the accuracy of diagnosis for different fault types, with clear distinction between the location of the fault and the boundary of the area, and no overlapping or blurred areas.

[0127] In another specific embodiment, the consistency between the isosceles right triangle method of this application and the Duval equilateral triangle method in the IEC 60599 standard is verified:

[0128] Step 1: Obtain 100 sets of insulating oil DGA data (covering partial discharge PD region, low-heat fault T1 region, medium-heat fault T2 region, high-heat fault T3 region, low-energy discharge D1 region, high-energy discharge D2 region, and mixed fault DT region, etc.), and perform fault diagnosis according to the Duval equilateral triangle in IEC 60599.

[0129] Step 2: Map the data to the coordinates (x, y) of this application, and determine the fault type based on the inequality intervals of this application;

[0130] Step 3: Statistically compare the diagnostic consistency between the two methods;

[0131] Result: The diagnostic results of the two methods were completely consistent;

[0132] Conclusion: The fault diagnosis results of this application are completely identical to the diagnostic results of the Duval equilateral triangle method in IEC 60599.

[0133] In another specific embodiment, the diagnosis of overheating faults inside a power transformer is as follows:

[0134] Equipment Information: 220kV oil-immersed self-cooled power transformer;

[0135] DGA data: =5μL / L, =10μL / L, =198μL / L;

[0136] Calculation process and fault diagnosis: Calculate separately and Volume percentage:

[0137] X= ;

[0138] Y= .

[0139] According to the internal fault detection method of insulating oil-filled power equipment provided in the embodiments of this application, X is used as the abscissa of the fault point and Y is used as the ordinate of the fault point. It is determined that the fault point falls into the high-heat fault T3 region, and the transformer has an overheat fault inside.

[0140] Fault verification: After disassembly, it was found that the bolts fixing the low-voltage lead to the bushing were not tightened, and the area was overheating, which was consistent with the diagnosis.

[0141] In another specific embodiment, the embedded online monitoring system implements:

[0142] Volumetric concentration was collected every 24 hours;

[0143] Normalization operation takes ≤10ms;

[0144] The target coordinates are mapped in ≤5ms.

[0145] Fault area identification takes ≤2ms;

[0146] The fault type is displayed via LCD (Liquid Crystal Display), and the data is uploaded in ≤3ms.

[0147] Performance indicators: Total time for a single diagnosis ≤20ms, power consumption ≤50mW, meeting the real-time requirements of online monitoring;

[0148] After continuously monitoring more than 1,800 sets of data from 6 main transformers, all target coordinate points were clearly located within their respective areas without any conflicting points or blurred boundaries, indicating that this application has stability and reliability in engineering applications.

[0149] Corresponding to the method for detecting internal faults in oil-filled power equipment provided in the embodiments of this application, the embodiments of this application also provide a device for detecting internal faults in oil-filled power equipment, such as... Figure 5 As shown, the internal fault detection device for insulating oil-filled power equipment includes:

[0150] The first acquisition module 501 is used to acquire insulating oil samples of insulating oil-filled power equipment in operation.

[0151] The detection module 502 is used to detect the volume concentration of three characteristic gases in the insulating oil sample;

[0152] The normalization processing module 503 is used to normalize the volume concentration of the characteristic gas to obtain the volume percentage of each characteristic gas in the total characteristic gas.

[0153] Module 504 is used to select two characteristic gases from three characteristic gases, as the first gas and the second gas respectively, and to construct a rectangular coordinate system with the volume percentage of the first gas as the horizontal axis variable and the volume percentage of the second gas as the vertical axis variable.

[0154] The first determining module 505 is used to determine the target area in the rectangular coordinate system as the fault diagnosis space. The target area is an isosceles right triangle: the origin of the coordinate system is the right-angle vertex of the isosceles right triangle, the right horizontal half-axis is the first right-angle side, the upper vertical half-axis is the second right-angle side, and the length of the first right-angle side and the second right-angle side is 100.

[0155] The partitioning module 506 is used to divide the target area into multiple non-overlapping fault areas according to the fault classification rules, wherein each fault area corresponds to a fault type.

[0156] The second acquisition module 507 is used to obtain the target coordinate point with the volume percentage of the first gas as the horizontal axis and the volume percentage of the second gas as the vertical axis.

[0157] The second determining module 508 is used to determine the target fault type based on the fault area where the target coordinate point is located.

[0158] Output module 509 is used to output the target fault type.

[0159] Corresponding to the method for detecting internal faults in oil-filled power equipment provided in this application, this application also provides an electronic device for performing the method for detecting internal faults in oil-filled power equipment, such as... Figure 6 As shown, the electronic device includes: a processor 601; and a memory 602 for storing a program for detecting internal faults in insulating oil-filled power equipment. After the device is powered on and the processor runs the program for detecting internal faults in insulating oil-filled power equipment, the following steps are performed:

[0160] Obtain insulating oil samples from insulating oil-filled power equipment in operation;

[0161] The volume concentrations of three characteristic gases in an insulating oil sample were detected.

[0162] The volume concentration of the characteristic gases is normalized to obtain the volume percentage of each characteristic gas in the total characteristic gases.

[0163] Two characteristic gases are selected from the three characteristic gases, namely the first gas and the second gas, and a rectangular coordinate system is constructed with the volume percentage of the first gas as the horizontal axis variable and the volume percentage of the second gas as the vertical axis variable.

[0164] The target area in the rectangular coordinate system is defined as the fault diagnosis space. The target area is an isosceles right triangle: the origin of the coordinate system is the right-angle vertex of the isosceles right triangle, the right horizontal axis is the first right-angled side, the upper vertical axis is the second right-angled side, and the length of the first right-angled side and the second right-angled side are both 100.

[0165] According to the fault classification rules, the target area is divided into multiple non-overlapping fault areas, where each fault area corresponds to a fault type.

[0166] The target coordinate point is obtained by plotting the volume percentage of the first gas on the x-axis and the volume percentage of the second gas on the y-axis.

[0167] Determine the type of target fault based on the fault area where the target coordinate point is located;

[0168] Output the target fault type.

[0169] Corresponding to the method for detecting internal faults in insulating oil-filled power equipment provided in the embodiments of this application, the embodiments of this application also provide a computer-readable storage medium storing a program for detecting internal faults in insulating oil-filled power equipment. This program is executed by a processor to perform the following steps:

[0170] Obtain insulating oil samples from insulating oil-filled power equipment in operation;

[0171] The volume concentrations of three characteristic gases in an insulating oil sample were detected.

[0172] The volume concentration of the characteristic gases is normalized to obtain the volume percentage of each characteristic gas in the total characteristic gases.

[0173] Two characteristic gases are selected from the three characteristic gases, namely the first gas and the second gas, and a rectangular coordinate system is constructed with the volume percentage of the first gas as the horizontal axis variable and the volume percentage of the second gas as the vertical axis variable.

[0174] The target area in the rectangular coordinate system is defined as the fault diagnosis space. The target area is an isosceles right triangle: the origin of the coordinate system is the right-angle vertex of the isosceles right triangle, the right horizontal axis is the first right-angled side, the upper vertical axis is the second right-angled side, and the length of the first right-angled side and the second right-angled side are both 100.

[0175] According to the fault classification rules, the target area is divided into multiple non-overlapping fault areas, where each fault area corresponds to a fault type.

[0176] The target coordinate point is obtained by plotting the volume percentage of the first gas on the x-axis and the volume percentage of the second gas on the y-axis.

[0177] Determine the type of target fault based on the fault area where the target coordinate point is located;

[0178] Output the target fault type.

[0179] Corresponding to the method for detecting internal faults in insulating oil-filled power equipment provided in the embodiments of this application, the embodiments of this application also provide a computer program containing instructions, which, when executed by a computer, cause the computer to perform the following steps:

[0180] Obtain insulating oil samples from insulating oil-filled power equipment in operation;

[0181] The volume concentrations of three characteristic gases in an insulating oil sample were detected.

[0182] The volume concentration of the characteristic gases is normalized to obtain the volume percentage of each characteristic gas in the total characteristic gases.

[0183] Two characteristic gases are selected from the three characteristic gases, namely the first gas and the second gas, and a rectangular coordinate system is constructed with the volume percentage of the first gas as the horizontal axis variable and the volume percentage of the second gas as the vertical axis variable.

[0184] The target area in the rectangular coordinate system is defined as the fault diagnosis space. The target area is an isosceles right triangle: the origin of the coordinate system is the right-angle vertex of the isosceles right triangle, the right horizontal axis is the first right-angled side, the upper vertical axis is the second right-angled side, and the length of the first right-angled side and the second right-angled side are both 100.

[0185] According to the fault classification rules, the target area is divided into multiple non-overlapping fault areas, where each fault area corresponds to a fault type.

[0186] The target coordinate point is obtained by plotting the volume percentage of the first gas on the x-axis and the volume percentage of the second gas on the y-axis.

[0187] Determine the type of target fault based on the fault area where the target coordinate point is located;

[0188] Output the target fault type.

[0189] It should be noted that for a detailed description of the internal fault detection device, electronic device, computer-readable storage medium and computer program product of the insulating oil-filled power equipment provided in the embodiments of this application, please refer to the relevant description of the embodiments of the internal fault detection method of the insulating oil-filled power equipment provided in the embodiments of this application, which will not be repeated here.

[0190] In a typical configuration, an electronic device includes one or more processors (Central Processing Units), input / output interfaces, network interfaces, and memory.

[0191] Memory may include non-persistent storage in computer-readable media, such as random access memory and / or non-volatile memory, like read-only memory or flash memory. Memory is an example of computer-readable media.

[0192] Computer-readable media, including both permanent and non-permanent, removable and non-removable media, can store information using any method or technology. Information can be computer-readable operations, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase-change memory, static random access memory, dynamic random access memory, other types of random access memory, read-only memory, electrically erasable programmable read-only memory, flash memory or other memory technologies, compact disc read-only memory, digital video disc or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include non-transitory computer-readable media, such as modulated data signals and carrier waves.

[0193] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage, compact disc read-only memory, optical storage, etc.) containing computer-usable program code.

[0194] Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of this application. Therefore, the scope of protection of this application should be determined by the scope defined in the claims of this application.

Claims

1. A method for detecting internal faults in insulating oil-filled power equipment, characterized in that, include: Obtain insulating oil samples from insulating oil-filled power equipment in operation; The volume concentrations of three characteristic gases in the insulating oil sample were detected. The volume concentration of the characteristic gas is normalized to obtain the volume percentage of each characteristic gas in the total characteristic gas. Two characteristic gases are selected from the three characteristic gases, respectively, as the first gas and the second gas, and a rectangular coordinate system is constructed with the volume percentage of the first gas as the horizontal axis variable and the volume percentage of the second gas as the vertical axis variable. The target region in the rectangular coordinate system is defined as the fault diagnosis space. The target region is an isosceles right triangle: the origin of the coordinate system is the right-angle vertex of the isosceles right triangle, the right horizontal half-axis is the first right-angle side, the upper vertical half-axis is the second right-angle side, and the length of the first right-angle side and the second right-angle side is 100. According to the fault classification rules, the target area is divided into multiple non-overlapping fault areas, where each fault area corresponds to a fault type. The target coordinate point is obtained by plotting the volume percentage of the first gas on the x-axis and the volume percentage of the second gas on the y-axis. The target fault type is determined based on the fault area where the target coordinate point is located. Output the target fault type; When the three characteristic gases are acetylene, ethylene, and methane, the fault region includes a partial discharge (PD) region, a low-temperature fault (T1) region, a medium-temperature fault (T2) region, a high-temperature fault (T3) region, a low-energy discharge (D1) region, a high-energy discharge (D2) region, and a mixed fault (DT) region. The high-energy discharge (D2) region includes a first high-energy electron discharge region and a second high-energy electron discharge region. The mixed fault (DT) region includes a first mixed fault sub-region, a second mixed fault sub-region, and a third mixed fault sub-region. The range of the partial discharge PD region is such that the sum of the volume percentages of the acetylene and the ethylene is not greater than 2. The range of the low-temperature fault T1 region is as follows: the volume percentage of acetylene is not greater than 4%, the volume percentage of ethylene is not greater than 20%, and the sum of the volume percentages of acetylene and ethylene is greater than 2. The area of ​​the intermediate thermal fault T2 region is defined as follows: the volume percentage of acetylene is not greater than 4%, and the volume percentage of ethylene is not less than 20% and not greater than 50%. The area of ​​the high-temperature fault T3 region is defined as follows: the volume percentage of acetylene is not greater than 15%, the volume percentage of ethylene is greater than 50%, and the sum of the volume percentages of acetylene and ethylene is not greater than 100%. The range of the low-energy discharge D1 region is as follows: the volume percentage of acetylene is greater than 13, the volume percentage of ethylene is not greater than 23, and the sum of the volume percentages of acetylene and ethylene is not greater than 100. The first high-energy electron discharge region is defined as follows: the volume percentage of acetylene is greater than 13 and not greater than 29, and the volume percentage of ethylene is greater than 23 and not greater than 40. The second high-energy electron discharge region is defined as follows: the volume percentage of acetylene is greater than 29%, the volume percentage of ethylene is greater than 23%, and the sum of the volume percentages of acetylene and ethylene is not greater than 100%. The region of the first mixed fault sub-region is: the volume percentage of acetylene is greater than 4 and not greater than 13, and the volume percentage of ethylene is not greater than 40. The region range of the second mixed fault sub-region is: the volume percentage of acetylene is greater than 4 and not greater than 29, and the volume percentage of ethylene is not less than 40 and not greater than 50. The third mixed fault sub-region is defined as follows: the volume percentage of acetylene is greater than 15 and not greater than 29, the volume percentage of ethylene is greater than 50, and the sum of the volume percentages of acetylene and ethylene is not greater than 100.

2. The method for detecting internal faults in insulating oil-filled power equipment according to claim 1, characterized in that, Different types of insulating oil-filled electrical equipment have different preset fault classification rules.

3. The method for detecting internal faults in insulating oil-filled power equipment according to claim 1, characterized in that, The three characteristic gases include the first gas, the second gas, and the third gas. The normalization of the volume concentrations of the characteristic gases to obtain the volume percentage of each characteristic gas in the total characteristic gases includes: The volume concentrations of the first gas and the second gas are normalized to obtain the volume percentages of the first gas and the second gas in the total characteristic gas. The volume percentage of the third gas in the total characteristic gas is calculated based on the following formula: ； in, This indicates the volume percentage of the third gas in the total characteristic gas. This indicates the volume percentage of the first gas in the total characteristic gas. This indicates the volume percentage of the second gas in the total characteristic gas.

4. The method for detecting internal faults in insulating oil-filled power equipment according to claim 1, characterized in that, The fault classification rules were determined by the IEC 60599 standard using the Duval equilateral triangle graphical tool.

5. The method for detecting internal faults in insulating oil-filled power equipment according to claim 4, characterized in that, The step of dividing the target area into multiple non-overlapping fault areas according to the fault classification rules includes: Based on the IEC 60599 standard, obtain the gas volume percentage thresholds corresponding to different fault types; The volume percentage threshold of the gas is converted into a linear boundary corresponding to the fault type; The target region is divided into multiple non-overlapping fault regions based on the linear boundary.

6. A fault detection device for internal electrical equipment filled with insulating oil, characterized in that, include: The first acquisition module is used to acquire insulating oil samples of insulating oil-filled power equipment in operation. The detection module is used to detect the volume concentration of three characteristic gases in the insulating oil sample; The normalization module is used to normalize the volume concentration of the characteristic gases to obtain the volume percentage of each characteristic gas in the total characteristic gases. The construction module is used to select two characteristic gases from the three characteristic gases, respectively as the first gas and the second gas, and construct a rectangular coordinate system with the volume percentage of the first gas as the horizontal axis variable and the volume percentage of the second gas as the vertical axis variable. The first determining module is used to determine the target area in the rectangular coordinate system as the fault diagnosis space. The target area is an isosceles right triangle: the origin of the coordinate system is the right-angle vertex of the isosceles right triangle, the right horizontal half-axis is the first right-angle side, the upper vertical half-axis is the second right-angle side, and the length of the first right-angle side and the second right-angle side is 100. The partitioning module is used to divide the target area into multiple non-overlapping fault regions according to fault classification rules, wherein each fault region corresponds to a fault type. The second acquisition module is used to obtain the target coordinate point by using the volume percentage of the first gas as the abscissa and the volume percentage of the second gas as the ordinate. The second determining module is used to determine the target fault type based on the fault area where the target coordinate point is located. The output module is used to output the target fault type; When the three characteristic gases are acetylene, ethylene, and methane, the fault region includes a partial discharge (PD) region, a low-temperature fault (T1) region, a medium-temperature fault (T2) region, a high-temperature fault (T3) region, a low-energy discharge (D1) region, a high-energy discharge (D2) region, and a mixed fault (DT) region. The high-energy discharge (D2) region includes a first high-energy electron discharge region and a second high-energy electron discharge region. The mixed fault (DT) region includes a first mixed fault sub-region, a second mixed fault sub-region, and a third mixed fault sub-region. The range of the partial discharge PD region is such that the sum of the volume percentages of the acetylene and the ethylene is not greater than 2. The range of the low-temperature fault T1 region is as follows: the volume percentage of acetylene is not greater than 4%, the volume percentage of ethylene is not greater than 20%, and the sum of the volume percentages of acetylene and ethylene is greater than 2. The area of ​​the intermediate thermal fault T2 region is defined as follows: the volume percentage of acetylene is not greater than 4%, and the volume percentage of ethylene is not less than 20% and not greater than 50%. The area of ​​the high-temperature fault T3 region is defined as follows: the volume percentage of acetylene is not greater than 15%, the volume percentage of ethylene is greater than 50%, and the sum of the volume percentages of acetylene and ethylene is not greater than 100%. The range of the low-energy discharge D1 region is as follows: the volume percentage of acetylene is greater than 13, the volume percentage of ethylene is not greater than 23, and the sum of the volume percentages of acetylene and ethylene is not greater than 100. The first high-energy electron discharge region is defined as follows: the volume percentage of acetylene is greater than 13 and not greater than 29, and the volume percentage of ethylene is greater than 23 and not greater than 40. The second high-energy electron discharge region is defined as follows: the volume percentage of acetylene is greater than 29%, the volume percentage of ethylene is greater than 23%, and the sum of the volume percentages of acetylene and ethylene is not greater than 100%. The region of the first mixed fault sub-region is: the volume percentage of acetylene is greater than 4 and not greater than 13, and the volume percentage of ethylene is not greater than 40. The region range of the second mixed fault sub-region is: the volume percentage of acetylene is greater than 4 and not greater than 29, and the volume percentage of ethylene is not less than 40 and not greater than 50. The third mixed fault sub-region is defined as follows: the volume percentage of acetylene is greater than 15 and not greater than 29, the volume percentage of ethylene is greater than 50, and the sum of the volume percentages of acetylene and ethylene is not greater than 100.

7. An electronic device, characterized in that, The method includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the method for detecting internal faults in insulating oil-filled power equipment as described in any one of claims 1-5.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the method for detecting internal faults in insulating oil-filled power equipment as described in any one of claims 1-5.

9. A computer program product comprising computer instructions, characterized in that, When the computer instructions are executed by the processor, they implement the method for detecting internal faults in insulating oil-filled power equipment as described in any one of claims 1-5.

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