Fault detection method, device, medium and computer equipment for same-tower non-transposition line

Abstract

The application discloses a same-tower non-transposition line fault detection method and device, medium and computer equipment, and relates to the field of power systems. The method comprises the following steps: firstly, obtaining line parameters of a target line, constructing a line model based on the line parameters, and obtaining an initial impedance matrix of the target line; then, performing parameter average processing on the initial impedance matrix to obtain an average impedance matrix; based on the average impedance matrix, establishing a voltage-current relationship formula of the target line to obtain an initial relationship formula; finally, decoupling the initial relationship formula to obtain a decoupled relationship formula and a decoupled matrix; and based on the decoupled relationship formula and the decoupled matrix, solving a fault boundary condition of the target line to obtain a fault current of the target line. The above method solves the problem that the fault current is difficult to solve due to the asymmetry of the loop parameters, reduces the calculation difficulty and the amount of calculation, and improves the accuracy of the calculation result.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power systems, and in particular to a same-tower non-transposition line fault detection method and device, a storage medium and computer equipment. BACKGROUND

[0002] With the rapid economic development and accelerated urbanization process, the demand for electricity continues to grow, and the scale of transmission line construction is expanding. However, the transmission corridor resources are scarce, the land is scarce and the land acquisition cost is increasing, resulting in rising construction costs. Under the demand for efficient use of limited transmission corridor resources, same-tower double-circuit and multi-circuit lines have been widely used as an economical and efficient transmission solution.

[0003] Same-tower non-transposition lines refer to two or more transmission lines arranged in parallel on the same tower, but not designed in the traditional way. Compared with traditional transmission lines, same-tower non-transposition lines have significant advantages, including saving land resources, significantly reducing construction costs, and improving transmission efficiency, and have become an important part of modern power grid construction. However, the non-transposed conductor arrangement will result in the line parameters of the same-tower double-circuit line being impossible to be completely symmetrical, thereby causing many problems for the fault analysis of the line, and it is difficult to meet the assumption conditions of the six-sequence component method to accurately analyze and calculate the fault current. SUMMARY

[0004] Therefore, the present application provides a same-tower non-transposition line fault detection method and device, a storage medium and computer equipment, which mainly aims to solve the technical problem of low accuracy of fault current calculation caused by the asymmetry of same-tower non-transposition line parameters.

[0005] According to a first aspect of the present application, a same-tower non-transposition line fault detection method is provided, which comprises:

[0006] Obtaining the line parameters of the target line, constructing a line model based on the line parameters, and obtaining the initial impedance matrix of the target line;

[0007] Performing parameter averaging processing on the initial impedance matrix to obtain an average impedance matrix, establishing a voltage-current relationship of the target line based on the average impedance matrix, and obtaining an initial relationship;

[0008] Decoupling the initial relationship to obtain a decoupling relationship and a decoupling matrix, and solving the fault boundary conditions of the target line based on the decoupling relationship and the decoupling matrix to obtain the fault current of the target line.

[0009] In an embodiment, the obtaining the line parameters of the target line, constructing a line model based on the line parameters, and obtaining an initial impedance matrix of the target line, comprises: obtaining the horizontal distance of each phase conductor of each loop in the target line from the center of the tower, the height of each phase conductor of each loop to the ground at the tower body, the voltage at the power generation end and the voltage at the power consumption end of the target line, the impedance at the power generation end and the impedance at the power consumption end of the target line, and constructing the line model; and obtaining the initial impedance matrix based on the line model, wherein the initial impedance matrix comprises self-induction parameters of each loop in the target line, mutual inductance parameters between phases of each loop, and mutual inductance parameters between lines of each loop.

[0010] In an embodiment, the parameter averaging processing of the initial impedance matrix to obtain an average impedance matrix comprises: obtaining the self-induction parameters of each loop in the initial impedance matrix, calculating the average of the self-induction parameters to obtain average self-induction parameters; obtaining the mutual inductance parameters between phases of each loop in the initial impedance matrix, calculating the average of the mutual inductance parameters between phases to obtain average mutual inductance parameters between phases; obtaining the mutual inductance parameters between lines of each loop in the initial impedance matrix, calculating the average of the mutual inductance parameters between lines to obtain average mutual inductance parameters between lines; and replacing the self-induction parameters, the mutual inductance parameters between phases, and the mutual inductance parameters between lines in the initial impedance matrix with the average self-induction parameters, the average mutual inductance parameters between phases, and the average mutual inductance parameters between lines respectively to obtain the average impedance matrix.

[0011] In an embodiment, the decoupling of the initial relationship to obtain a decoupled relationship and a decoupling matrix comprises: obtaining an inter-phase decoupling matrix, and inter-phase decoupling the initial relationship based on the inter-phase decoupling matrix to obtain an inter-phase decoupled relationship; obtaining an inter-line decoupling matrix, and inter-line decoupling the inter-phase decoupled relationship based on the inter-line decoupling matrix to obtain the decoupled relationship; and obtaining the decoupling matrix based on the inter-phase decoupling matrix and the inter-line decoupling matrix.

[0012] In an embodiment, the obtaining of the inter-phase decoupling matrix, and the inter-phase decoupling of the initial relationship based on the inter-phase decoupling matrix to obtain an inter-phase decoupled relationship comprises:

[0013] [ΔU ABC ]=[Z eq ][I ABC ];

[0014]

[0015] [ΔU 012 ]=[Q] -1 [Z eq ][Q][I 012 ];

[0016] wherein [ΔU ABC ] is an initial voltage matrix, [I ABC ] is an initial current matrix, [Z eq ] is an average impedance matrix, [ΔU 012 ] is an inter-phase decoupling voltage matrix, [I 012 ] is an inter-phase decoupling current matrix, and [Q] is an inter-phase decoupling matrix.

[0017] In an embodiment, the obtaining the inter-line decoupling matrix, and performing inter-line decoupling on the inter-phase decoupling relationship based on the inter-line decoupling matrix to obtain the decoupling relationship, comprises:

[0018]

[0019] [ΔU' 012 ] = [P] -1 [Q] -1 [Z eq ][Q][P][I' 012 ];

[0020] wherein [ΔU' 012 ] is a decoupling voltage matrix, [I' 012 ] is a decoupling current matrix, and [P] is an inter-line decoupling matrix.

[0021] The obtaining the decoupling matrix based on the inter-phase decoupling matrix and the inter-line decoupling matrix, comprises:

[0022] [M] = [Q][P];

[0023] wherein [M] is the decoupling matrix.

[0024] In an embodiment, the solving the fault boundary condition of the target line based on the decoupling relationship and the decoupling matrix to obtain the fault current of the target line, comprises: converting the fault boundary condition into a decoupling boundary condition based on the decoupling matrix, obtaining a composite sequence network graph based on the decoupling relationship and the decoupling boundary condition; and calculating the fault current of the target line based on the composite sequence network graph.

[0025] According to a second aspect of the present application, there is provided a fault detection device for a same-tower non-transposed line, which comprises:

[0026] a model construction module, configured to obtain line parameters of a target line, and construct a line model based on the line parameters to obtain an initial impedance matrix of the target line;

[0027] The data processing module is configured to perform parameter averaging processing on the initial impedance matrix to obtain an average impedance matrix, and establish a voltage-current relationship of the target line based on the average impedance matrix to obtain an initial relationship;

[0028] The decoupling calculation module is configured to decouple the initial relationship to obtain a decoupled relationship and a decoupling matrix, and solve a fault boundary condition of the target line based on the decoupled relationship and the decoupling matrix to obtain a fault current of the target line.

[0029] According to a third aspect of the present application, a storage medium is provided, which stores a computer program, and the program is executed by a processor to implement the above-mentioned fault detection method for the same-tower non-transposed line.

[0030] According to a fourth aspect of the present application, a computer device is provided, which comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the above-mentioned fault detection method for the same-tower non-transposed line when executing the program.

[0031] The fault detection method, device, storage medium and computer device for the same-tower non-transposed line provided by the present application first obtain the line parameters of the target line, construct a line model based on the line parameters to obtain an initial impedance matrix of the target line, then perform parameter averaging processing on the initial impedance matrix to obtain an average impedance matrix, establish a voltage-current relationship of the target line based on the average impedance matrix to obtain an initial relationship, and finally decouple the initial relationship to obtain a decoupled relationship and a decoupling matrix, and solve a fault boundary condition of the target line based on the decoupled relationship and the decoupling matrix to obtain a fault current of the target line. By the above technical solution, the initial impedance matrix is first subjected to parameter averaging processing to obtain an average impedance matrix, which facilitates subsequent decoupling operation. Then, a relationship is established based on the average impedance matrix, and the relationship is decoupled to obtain a decoupled relationship and a decoupling matrix, so that the boundary condition can be solved based on the decoupled relationship and the decoupling matrix, the problem of being difficult to solve the fault current due to the asymmetry of the loop parameters is solved, the calculation difficulty and the amount of calculation are reduced, and the accuracy of the calculation result is improved.

[0032] The above description is only a summary of the technical solutions of the present application. In order to more clearly understand the technical means of the present application, the specific embodiments of the present application can be implemented in accordance with the content of the description, and in order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following specific embodiments of the present application are described. BRIEF DESCRIPTION OF DRAWINGS

[0033] The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the application. In the drawings:

[0034] Figure 1 A flowchart of a same-tower non-transposition line fault detection method provided by an embodiment of the application is shown in the figure;

[0035] Figure 2 A line parameter diagram provided by an embodiment of the application is shown in the figure;

[0036] Figure 3 A double-circuit line structure diagram provided by an embodiment of the application is shown in the figure;

[0037] Figure 4 A I-circuit line A-phase ground fault composite sequence network diagram provided by an embodiment of the application is shown in the figure;

[0038] Figure 5 A structure diagram of a same-tower non-transposition line fault detection device provided by an embodiment of the application is shown in the figure;

[0039] Figure 6 A structure diagram of a computer device provided by an embodiment of the application is shown in the figure. DETAILED DESCRIPTION

[0040] The application will be described in detail below with reference to the drawings and embodiments. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0041] With the rapid economic development and accelerated urbanization process, the demand for electricity continues to grow, especially in the economically developed East China region, the balance between supply and demand of electricity is prominent. East China Grid has formed a 500kV main network covering five provinces and cities, and the construction scale of transmission lines is expanding, but the transmission corridor resources are tight, the land is scarce and the land acquisition cost is increasing, resulting in rising construction costs. Under the demand for efficient use of limited transmission corridor resources, same-tower double-circuit and multi-circuit lines as an economic and efficient power transmission scheme have been widely used.

[0042] The same-tower non-transposed line refers to two or more power transmission lines arranged in parallel on the same tower, but not designed in the traditional transposed manner. Compared with the traditional power transmission line, the same-tower non-transposed line has significant advantages, including saving land resources, greatly reducing construction cost and improving power transmission efficiency, and has become an important part of modern power grid construction. However, the non-transposed conductor arrangement will lead to the fact that the line parameters of the same-tower double-circuit line cannot be completely symmetrical, thereby bringing many problems for the fault analysis of the line. The traditional six-sequence component method has achieved good results in the fault analysis of the same-tower double-circuit line, but its application premise is that the mutual inductance and self-inductance of the two circuits are completely the same, and the symmetry of the impedance matrix is required to be very high. Due to the different types of conductors used and the non-transposed design, it is difficult for the non-transposed same-tower line to meet the assumption conditions of the six-sequence component method to accurately analyze and calculate the short-circuit current.

[0043] Based on the above problems, the embodiment of the present application provides a fault detection method for a same-tower non-transposed line. In one embodiment, as shown in the method includes the following steps: Figure 1

[0044] 101. Obtain the line parameters of the target line, construct a line model based on the line parameters, and obtain the initial impedance matrix of the target line.

[0045] 102. Perform parameter averaging processing on the initial impedance matrix to obtain an average impedance matrix, establish a voltage-current relationship of the target line based on the average impedance matrix, and obtain an initial relationship.

[0046] 103. Decouple the initial relationship to obtain a decoupled relationship and a decoupling matrix, solve the fault boundary conditions of the target line based on the decoupled relationship and the decoupling matrix, and obtain the fault current of the target line.

[0047] In this embodiment, the target line is a same-tower non-transposed line, that is, two or more power transmission lines are arranged in parallel on the same tower, but not designed in the transposed manner. Based on the line parameters of the target line, a line model of the target line can be constructed, and the line model can be simulated and constructed by using related software or algorithms. Based on the line model, the impedance matrix of the target line can be calculated. In order to facilitate description, this impedance matrix is denoted as the initial impedance matrix.

[0048] ​Since the parameters on each line are not completely symmetrical due to process, environment, operation arrangement and other reasons in actual application of the target line, the initial impedance matrix calculated usually does not have regularity, and if direct operation is performed based on the initial impedance matrix, the difficulty of solving is very high and the amount of operation is also extremely large. Therefore, before solving, the initial impedance matrix is first processed in the first step, that is, parameter average processing, to convert the initial impedance matrix without regularity into an average impedance matrix with certain regularity.

[0049] After obtaining the average impedance matrix, a relationship between voltage and current is established based on the average impedance matrix, which is recorded as an initial relationship. Then the second step processing is performed, that is, decoupling based on the initial relationship. The initial relationship is that the initial voltage matrix is equal to the average impedance matrix multiplied by the initial current matrix. Although the average impedance matrix is processed based on the initial impedance matrix, it is still difficult to solve based on the average impedance matrix for operation, and therefore the initial relationship is decoupled to obtain a decoupled relationship and a decoupling matrix. The purpose of decoupling is to decouple the relationship into the form of the voltage matrix being equal to the diagonal matrix multiplied by the current matrix, so that the solving can be relatively convenient. After obtaining the decoupled relationship and the decoupling matrix, the target line can be solved according to the boundary condition of the fault, so as to calculate the fault current of the target line.

[0050] The fault detection method for the same-tower non-transposition line provided by the embodiment first acquires the line parameters of the target line, constructs a line model based on the line parameters, obtains an initial impedance matrix of the target line, then performs parameter average processing on the initial impedance matrix to obtain an average impedance matrix, establishes a voltage-current relationship of the target line based on the average impedance matrix to obtain an initial relationship, finally decouples the initial relationship to obtain a decoupled relationship and a decoupling matrix, and solves the boundary condition of the fault of the target line based on the decoupled relationship and the decoupling matrix to obtain the fault current of the target line. By the above technical solution, the initial impedance matrix is first processed by parameter average processing to obtain the average impedance matrix, which facilitates the subsequent decoupling operation. Then the relationship is established based on the average impedance matrix, and the decoupled relationship and the decoupling matrix are obtained by decoupling the relationship, so that the boundary condition can be solved based on the decoupled relationship and the decoupling matrix, the problem that the fault current is difficult to solve due to the asymmetry of the loop parameters is solved, the calculation difficulty and the amount of operation are reduced, and the accuracy of the calculation result is improved.

[0051] Further, in order to complete the description of the implementation process of the embodiment, the specific implementation of the above embodiment is detailed and expanded below. Specifically, in one embodiment, step 101 obtains the line parameters of the target line, constructs a line model based on the line parameters, and obtains an initial impedance matrix of the target line, including: obtaining the horizontal distance of each phase conductor of each loop in the target line from the tower center, the ground height of each phase conductor of each loop at the tower body, the generation end voltage and the power end voltage of the target line, the generation end impedance and the power end impedance of the target line, and constructing the line model; and calculating the initial impedance matrix based on the line model, wherein the initial impedance matrix includes the self-induction parameters of each loop in the target line, the mutual inductance parameters between phases of each loop, and the mutual inductance parameters between lines of each loop.

[0052] In the above embodiment, each line in the target line includes A, B, and C three phases, as shown in Figure 2 , taking two loops of loop I and loop II in the target line as an example, each loop includes A, B, and C three phase conductors. The line parameters of the target line can include the horizontal distance of each phase conductor in each loop from the tower center (i.e. the HORIZ parameter in Figure 2 ), the ground height of each phase conductor of each loop at the tower body (i.e. the VTOWER parameter in Figure 2 ), and also includes the horizontal distance of the ground wire from the tower center and the ground height at the tower body. The line parameters also include the generation end voltage and the power end voltage of the target line, and the generation end impedance and the power end impedance of the target line. For example, the same-tower double-loop structure is shown in Figure 3 , and Figure 3 , where E M represents the generation end voltage, E N represents the power end voltage, Z M represents the generation end impedance, and Z N represents the power end impedance. Based on the above line parameters, a simulation model of the target line is constructed by a related algorithm or software to obtain a line model, and based on the line model, the initial impedance matrix of the target line can be calculated. The initial impedance matrix is as follows:

[0053]

[0054] wherein the matrix Z is the initial impedance matrix, and the matrix parameter Z ij represents the impedance between loop conductor i and conductor j, each loop in the double loop includes A, B, and C three phase conductors, so there are 6 conductors, and the range of i and j is 1 to 6, for example, 1 to 3 can represent A, B, and C three phases of the first loop respectively, and 4 to 6 can represent A, B, and C three phases of the second loop respectively. For example, in the above formula, z 11This represents the self-impedance of phase A of the first circuit, also known as the self-inductance parameter, z. 12 This represents the mutual impedance between phases A and B of the first circuit, also known as the interphase mutual inductance parameter, z. 14 This represents the mutual impedance between phase A of the first circuit and phase A of the second circuit, also known as the inter-line mutual inductance parameter.

[0055] Based on the above, we know that the initial impedance matrix includes self-inductance parameters, phase-to-phase mutual inductance parameters, and line-to-line mutual inductance parameters.

[0056] Generally, the parameters of the first circuit (Circuit I) and the second circuit (Circuit II) are asymmetrical, so the parameters in the calculated initial impedance matrix are different and lack regularity. For example, taking... Figure 2 The line parameters shown are set to 500kV for both the generator and consumer voltages, i.e., E. M =E N =500kV, positive sequence impedance at the generator terminal is Z sm1 =0.3032+7.6348i, zero-sequence impedance is Z sm0 =1.5435+10.6116i, the positive sequence impedance of the terminal is Z. sn1 =0.3032+9.3988i, zero-sequence impedance is Z sn0 =1.4884+13.23i, and the initial impedance matrix calculated based on the above parameters is as follows:

[0057]

[0058] If calculations are performed directly based on the initial impedance matrix, the computational difficulty and workload are enormous, making complete decoupling difficult. Therefore, in this embodiment, the initial impedance matrix is ​​first subjected to parameter averaging to give the impedance matrix a certain regularity for subsequent calculations.

[0059] In one embodiment, step 102, performing parameter averaging on the initial impedance matrix to obtain an average impedance matrix, includes: obtaining the self-inductance parameter of each loop in the initial impedance matrix, calculating the average value of the self-inductance parameter to obtain an average self-inductance parameter; obtaining the phase-to-phase mutual inductance parameter of each loop in the initial impedance matrix, calculating the average value of the phase-to-phase mutual inductance parameter to obtain an average phase-to-phase mutual inductance parameter; obtaining the line-to-line mutual inductance parameter of each loop in the initial impedance matrix, calculating the average value of the line-to-line mutual inductance parameter to obtain an average line-to-line mutual inductance parameter; and replacing the self-inductance parameter, phase-to-phase mutual inductance parameter, and line-to-line mutual inductance parameter in the initial impedance matrix with the average self-inductance parameter, the average phase-to-phase mutual inductance parameter, and the average line-to-line mutual inductance parameter, respectively, to obtain the average impedance matrix.

[0060] Specifically, based on the formula 1, the average value of the self-induction parameter is calculated to obtain the average self-induction parameter, which includes:

[0061]

[0062] The average value of the mutual inductance parameter is calculated to obtain the average mutual inductance parameter, which includes:

[0063]

[0064] The average value of the mutual inductance parameter is calculated to obtain the average mutual inductance parameter, which includes:

[0065]

[0066] The results obtained by the above formula 2 to formula 7 are substituted into formula 1, and the average self-induction parameter, the average mutual inductance parameter and the average mutual inductance parameter are respectively replaced by the self-induction parameter, the mutual inductance parameter and the mutual inductance parameter in the initial impedance matrix in formula 1 to obtain the average impedance matrix, which is as follows:

[0067]

[0068] Where [Z eq ] represents the average impedance matrix, and it can be seen that the matrix has high symmetry and can realize complete decoupling.

[0069] In the above embodiment, the average impedance matrix obtained after the initial impedance matrix is subjected to parameter averaging processing is as follows:

[0070]

[0071] In one embodiment, the initial relationship is decoupled in step 103 to obtain a decoupled relationship and a decoupling matrix, which includes: obtaining an inter-phase decoupling matrix, and performing inter-phase decoupling on the initial relationship based on the inter-phase decoupling matrix to obtain an inter-phase decoupled relationship; obtaining an inter-line decoupling matrix, and performing inter-line decoupling on the inter-phase decoupled relationship based on the inter-line decoupling matrix to obtain the decoupled relationship; and obtaining the decoupling matrix based on the inter-phase decoupling matrix and the inter-line decoupling matrix.

[0072] Specifically, the inter-phase decoupling matrix is obtained, and the initial relationship is decoupled based on the inter-phase decoupling matrix to obtain an inter-phase decoupled relationship, which includes:

[0073] [ΔU ABC ]=[Z eq ][I ABC ]; (formula 9)

[0074]

[0075] [ΔU 012 ] = [Q] -1 [Z eq ][Q][I 012 ]; (Formula 11)

[0076] Among them, [ΔU ABC [I] represents the initial voltage matrix. ABC [Z] is the initial current matrix. eq ] is the average impedance matrix, [ΔU 012 [I] represents the phase-to-phase decoupling voltage matrix. 012 [Q] is the phase-to-phase decoupling current matrix, and [Q] is the phase-to-phase decoupling matrix.

[0077] Formula 9 is the initial relation, which is expanded as follows:

[0078]

[0079] In the above formula, ΔU IA , ΔU IB , ΔU IC , ΔU IIA ΔU IIB , ΔU IIC These represent the voltage drop of each phase on the line; I IA I IB I IC I IIA I IIB I IIC These represent the current in each phase of the line.

[0080] The phase decoupling matrix [Q] is as follows:

[0081]

[0082] Where a = e j120 .

[0083] Based on Equations 10 and 11, Equation 9 is decoupled into positive, negative, and zero sequences to obtain the phase decoupling relationship, which is as follows:

[0084]

[0085] After phase-to-phase decoupling, the positive and negative sequence impedances of the impedance matrix are completely decoupled, but zero-sequence coupling still exists between loops. Therefore, line-to-line decoupling is further performed.

[0086] Specifically, the process involves obtaining the inter-line decoupling matrix, and then performing inter-line decoupling on the inter-phase decoupling equation based on the inter-line decoupling matrix to obtain the decoupling equation, including:

[0087]

[0088] [ΔU' 012 ] = [P] -1 [Q] -1 [Z eq ][Q][P][I' 012 ]; (Formula 16)

[0089] Among them, [ΔU' 012 [I'] represents the decoupling voltage matrix. 012 [P] is the decoupling current matrix, and [P] is the line-to-line decoupling matrix;

[0090] The line decoupling matrix [P] is as follows:

[0091]

[0092] in,

[0093]

[0094] Based on Equations 15 and 16, the decoupling relationship between lines is obtained as follows:

[0095]

[0096] Formula 18 can be expressed in the following form:

[0097] [ΔU' 012 ] = [M] -1 [Z eq ][M][I' 012 ]; (Formula 19)

[0098] Where [M] = [Q][P]; (Formula 20)

[0099] Wherein, [M] is the decoupling matrix, which is expanded as follows:

[0100]

[0101] As can be seen from Formula 18, after two transformations, the voltage-current relationship has been completely decoupled, and the fault current can be solved based on this.

[0102] In one embodiment, the fault boundary condition of the target line is solved based on the decoupling relationship and the decoupling matrix to obtain a fault current of the target line, including: the fault boundary condition is converted into a decoupling boundary condition based on the decoupling matrix, and a composite sequence network diagram is obtained based on the decoupling relationship and the decoupling boundary condition; and the fault current of the target line is calculated based on the composite sequence network diagram.

[0103] Specifically, the fault boundary condition can be obtained according to the fault type, such as I-phase ground short circuit of I-loop line, BC-phase short circuit of I-loop line, B-phase and C-phase cross-line short circuit of I-loop line and II-loop line, and the like, and then the fault boundary condition is converted into a decoupling boundary condition based on the decoupling matrix, and then the decoupling boundary condition is solved. Taking the fault type of I-phase ground short circuit of I-loop line as an example, when the I-phase ground short circuit of I-loop line occurs, the A-phase voltage of I-loop line is zero, the fault currents of non-fault phases B and C are zero, and the three-phase fault currents of II-loop line are all zero. Thus, the fault boundary condition is obtained as follows:

[0104]

[0105] The above fault boundary condition is converted into a decoupling boundary condition based on the decoupling matrix as follows:

[0106]

[0107] The formula 23 is solved to obtain:

[0108]

[0109] Then, the composite sequence network diagram as shown in FIG. 6 is obtained based on the decoupling relationship, the decoupling boundary condition and the relationship between the voltages and currents of each sequence network, and the fault current of the target line, i.e., the short circuit current of the fault phase A, is calculated based on the composite sequence network diagram as follows: Figure 4

[0110]

[0111] The fault current of other fault types is solved in a similar way to the above embodiment, and thus will not be described herein.

[0112] The fault currents of different fault types are calculated by MATLAB, and compared with the fault currents calculated by the method provided in the embodiments of the present application, and the calculation error is within 5% as shown in the following table:

[0113]

[0114] ​The same-tower non-transposition line fault detection method provided by the embodiment can convert the initial impedance matrix that cannot be completely decoupled into an average impedance matrix that can be completely decoupled through parameter average processing of the impedance matrix. Then, a voltage-current relationship is established through the average impedance matrix to obtain an initial relationship. The initial relationship is sequentially subjected to inter-phase decoupling and inter-line decoupling to obtain a decoupling relationship and a decoupling matrix. The decoupling relationship is used to transform the impedance matrix to obtain a diagonal matrix, thereby achieving complete decoupling. Then, the fault boundary condition is solved based on the decoupling relationship and the decoupling matrix to calculate the fault current. Through the above manner, the asymmetric loop parameter can be solved and operated, the solving process is simplified, the operation amount is reduced, and the accuracy of the calculation result is improved.

[0115] Further, as Figure 1 and the specific implementation of the method shown in the above embodiment, the embodiment provides a same-tower non-transposition line fault detection device. Figure 5 As shown in the figure, the device comprises a model construction module 31, a data processing module 32, and a decoupling calculation module 33.

[0116] The model construction module 31 can be used to obtain the line parameters of a target line, construct a line model based on the line parameters, and obtain an initial impedance matrix of the target line.

[0117] The data processing module 32 can be used to perform parameter average processing on the initial impedance matrix to obtain an average impedance matrix, establish a voltage-current relationship of the target line based on the average impedance matrix, and obtain an initial relationship.

[0118] The decoupling calculation module 33 can be used to decouple the initial relationship to obtain a decoupling relationship and a decoupling matrix, and solve the fault boundary condition of the target line based on the decoupling relationship and the decoupling matrix to obtain the fault current of the target line.

[0119] In a specific application scenario, the line parameters of a target line are obtained, a line model is constructed based on the line parameters, and an initial impedance matrix of the target line is obtained. The model construction module 31 can be specifically used to obtain the horizontal distance of each phase conductor of each loop from the tower center, the height of each phase conductor of each loop to the ground of the tower body, the voltage of the power generation end and the voltage of the power consumption end of the target line, and the impedance of the power generation end and the impedance of the power consumption end of the target line, and the line model is constructed. The initial impedance matrix is calculated based on the line model, wherein the initial impedance matrix comprises self-induction parameters of each loop in the target line, inter-phase mutual inductance parameters of each loop, and inter-line mutual inductance parameters of each loop.

[0120] In a specific application scenario, the initial impedance matrix is subjected to parameter averaging processing to obtain an average impedance matrix. The data processing module 32 can specifically be configured to obtain a self-induction parameter of each loop in the initial impedance matrix, calculate an average value of the self-induction parameter to obtain an average self-induction parameter, obtain a mutual inductance parameter between phases of each loop in the initial impedance matrix, calculate an average value of the mutual inductance parameter between phases to obtain an average mutual inductance parameter between phases, and obtain a mutual inductance parameter between lines of each loop in the initial impedance matrix, calculate an average value of the mutual inductance parameter between lines to obtain an average mutual inductance parameter between lines. The average self-induction parameter, the average mutual inductance parameter between phases, and the average mutual inductance parameter between lines are respectively replaced by the self-induction parameter, the mutual inductance parameter between phases, and the mutual inductance parameter between lines in the initial impedance matrix to obtain the average impedance matrix.

[0121] In a specific application scenario, the initial relationship is decoupled to obtain a decoupled relationship and a decoupled matrix. The decoupling calculation module 33 can specifically be configured to obtain an inter-phase decoupling matrix, perform inter-phase decoupling on the initial relationship based on the inter-phase decoupling matrix to obtain an inter-phase decoupled relationship, obtain an inter-line decoupling matrix, perform inter-line decoupling on the inter-phase decoupled relationship based on the inter-line decoupling matrix to obtain the decoupled relationship, and obtain the decoupled matrix based on the inter-phase decoupling matrix and the inter-line decoupling matrix.

[0122] In a specific application scenario, the decoupling calculation module 33 can specifically be configured to obtain an inter-phase decoupling matrix, perform inter-phase decoupling on an initial relationship based on the inter-phase decoupling matrix to obtain an inter-phase decoupled relationship, and include:

[0123] [ΔU ABC ]=[Z eq ][I ABC ];

[0124]

[0125] [ΔU 012 ]=[Q] -1 [Z eq ][Q][I 012 ];

[0126] Wherein, [ΔU ABC ] is an initial voltage matrix, [I ABC ] is an initial current matrix, [Z eq ] is an average impedance matrix, [ΔU 012 ] is an inter-phase decoupled voltage matrix, [I 012 ] is an inter-phase decoupled current matrix, and [Q] is an inter-phase decoupling matrix.

[0127] In a specific application scenario, the decoupling calculation module 33 can be specifically used to obtain an inter-line decoupling matrix, and obtain the decoupling relationship based on the inter-line decoupling matrix and the inter-phase decoupling relationship, and the decoupling relationship includes:

[0128]

[0129] [ΔU' 012 ]=[P] -1 [Q] -1 [Z eq ][Q][P][I' 012 ];

[0130] Wherein, [ΔU' 012 ] is a decoupling voltage matrix, [I' 012 ] is a decoupling current matrix, and [P] is an inter-line decoupling matrix.

[0131] The decoupling matrix is obtained based on the inter-phase decoupling matrix and the inter-line decoupling matrix, and the decoupling calculation module 33 can be specifically used to obtain the decoupling matrix based on the inter-phase decoupling matrix and the inter-line decoupling matrix.

[0132] [M]=[Q][P];

[0133] Wherein, [M] is the decoupling matrix.

[0134] In a specific application scenario, the decoupling calculation module 33 can be specifically used to obtain the decoupling matrix based on the decoupling relationship and the decoupling matrix, and the decoupling calculation module 33 can be specifically used to obtain the decoupling matrix based on the decoupling relationship and the decoupling matrix.

[0135] It should be noted that the other corresponding description of each functional unit involved in the same-tower non-transposition line fault detection device provided in the embodiment can be referred to Figure 1 and the corresponding description in the above embodiment, which will not be repeated here.

[0136] The embodiment of the application further provides a computer device, such as Figure 6As shown, the computer device can be a personal computer, a server, a network device, etc., and the computer device includes a system bus, a processor, a memory and a communication interface, and can further include an input / output interface and a display device. The processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for running the operating system and the computer program in the non-volatile storage medium. The database of the computer device is configured to store location information. The network interface of the computer device is configured to communicate with an external terminal through a network connection. The computer program is executed by the processor to implement the steps in the method embodiments.

[0137] Those skilled in the art can understand that the structure of the computer device described above is only part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. The specific computer device can include more or fewer components, or combine certain components, or have a different arrangement of components.

[0138] In one embodiment, a computer readable storage medium is provided, which can be non-volatile or volatile, and has stored thereon a computer program. The computer program is executed by the processor to implement the steps in the method embodiments described above.

[0139] In one embodiment, a computer program product is provided, which includes a computer program. The computer program is executed by the processor to implement the steps in the method embodiments described above.

[0140] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer readable storage medium, and when the computer program is executed, the processes of the above-mentioned embodiments of the methods can be included. Any reference to memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (Read-Only Memory, ROM), magnetic tape, floppy disk, flash memory, optical storage, high-density embedded non-volatile memory, resistive memory (ReRAM), magnetoresistive random access memory (Magnetoresistive Random Access Memory, MRAM), ferroelectric memory (Ferroelectric Random Access Memory, FRAM), phase change memory (Phase Change Memory, PCM), graphene memory, etc. Volatile memory can include random access memory (Random Access Memory, RAM) or external cache memory, etc. As an illustration but not limitation, the RAM can be in various forms, such as static random access memory (Static Random Access Memory, SRAM) or dynamic random access memory (Dynamic Random Access Memory, DRAM), etc. The database involved in the embodiments provided in the present application can include at least one of a relational database and a non-relational database. The non-relational database can include a distributed database based on a block chain, etc., without being limited thereto. The processor involved in the embodiments provided in the present application can be a general-purpose processor, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., without being limited thereto.

[0141] Any combination of the technical features of the above embodiments can be made. In order to make the description simple, all possible combinations of the technical features in the above embodiments are not described, however, as long as the combination of the technical features does not exist contradictory, it should be considered as the scope of the present application.

[0142] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent of the present application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of protection of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A method for detecting faults in lines on the same tower without transposition, characterized in that, The method includes: Obtain the line parameters of the target line, construct a line model based on the line parameters, and obtain the initial impedance matrix of the target line; The initial impedance matrix is ​​subjected to parameter averaging to obtain an average impedance matrix. Based on the average impedance matrix, the voltage-current relationship of the target line is established to obtain the initial relationship. The initial relation is decoupled to obtain a decoupling relation and a decoupling matrix. Based on the decoupling relation and the decoupling matrix, the fault boundary conditions of the target line are solved to obtain the fault current of the target line. The step of averaging the initial impedance matrix to obtain the average impedance matrix includes: Obtain the self-inductance parameter of each loop in the initial impedance matrix, calculate the average value of the self-inductance parameter, and obtain the average self-inductance parameter; Obtain the phase-to-phase mutual inductance parameters of each loop in the initial impedance matrix, calculate the average value of the phase-to-phase mutual inductance parameters, and obtain the average phase-to-phase mutual inductance parameters. Obtain the mutual inductance parameters of each loop in the initial impedance matrix, calculate the average value of the mutual inductance parameters, and obtain the average mutual inductance parameters. The average impedance matrix is ​​obtained by replacing the self-inductance parameter, the phase-to-phase mutual inductance parameter, and the line-to-line mutual inductance parameter in the initial impedance matrix with the average self-inductance parameter, the average phase-to-phase mutual inductance parameter, and the average line-to-line mutual inductance parameter, respectively.

2. The method according to claim 1, characterized in that, The process of obtaining the line parameters of the target line, constructing a line model based on the line parameters, and obtaining the initial impedance matrix of the target line includes: The horizontal distance of each phase conductor of each loop in the target line from the center of the tower, the height of each phase conductor of each loop above the ground on the tower, the generator voltage and the consumer voltage of the target line, and the generator impedance and the consumer impedance of the target line are obtained to construct the line model. The initial impedance matrix is ​​calculated based on the line model, wherein the initial impedance matrix includes the self-inductance parameter of each loop in the target line, the phase-to-phase mutual inductance parameter of each loop, and the line-to-line mutual inductance parameter of each loop.

3. The method according to claim 1, characterized in that, The process of decoupling the initial relation to obtain the decoupling relation and the decoupling matrix includes: Obtain the phase decoupling matrix, and perform phase decoupling on the initial relation based on the phase decoupling matrix to obtain the phase decoupling relation; Obtain the inter-line decoupling matrix, and perform inter-line decoupling on the inter-phase decoupling relationship based on the inter-line decoupling matrix to obtain the decoupling relationship; The decoupling matrix is ​​obtained based on the phase-to-phase decoupling matrix and the line-to-line decoupling matrix.

4. The method according to claim 3, characterized in that, The step of obtaining the interphase decoupling matrix and then performing interphase decoupling on the initial relation based on the interphase decoupling matrix to obtain the interphase decoupling relation includes: [ΔU ABC ]=[Z eq ][AND ABC ]; [ΔU 012 ]=[Q] -1 [WITH eq ][Q][I 012 ]; Among them, [ΔU ABC [I] represents the initial voltage matrix. ABC [Z] is the initial current matrix. eq ] is the average impedance matrix, [ΔU 012 [I] represents the phase-to-phase decoupling voltage matrix. 012 [Q] is the phase-to-phase decoupling current matrix, and [Q] is the phase-to-phase decoupling matrix.

5. The method according to claim 4, characterized in that, The step of obtaining the inter-line decoupling matrix and then performing inter-line decoupling on the inter-phase decoupling relationship based on the inter-line decoupling matrix to obtain the decoupling relationship includes: [ΔU' 012 ]=[P] -1 [Q] -1 [WITH eq ][Q][P][I' 012 ]; Among them, [ΔU' 012 [I'] represents the decoupling voltage matrix. 012 [P] is the decoupling current matrix, and [P] is the line-to-line decoupling matrix; The process of obtaining the decoupling matrix based on the phase-to-phase decoupling matrix and the line-to-line decoupling matrix includes: [M] = [Q][P]; Wherein, [M] is the decoupling matrix.

6. The method according to claim 1, characterized in that, The step of solving the fault boundary conditions of the target line based on the decoupling relationship and the decoupling matrix to obtain the fault current of the target line includes: Based on the decoupling matrix, the fault boundary conditions are transformed into decoupling boundary conditions, and a composite sequence network graph is obtained based on the decoupling relation and the decoupling boundary conditions. The fault current of the target line is calculated based on the composite sequence network diagram.

7. A fault detection device for lines on the same tower without transposition, characterized in that, The device includes: The model building module is used to obtain the line parameters of the target line, build a line model based on the line parameters, and obtain the initial impedance matrix of the target line. The data processing module is used to perform parameter averaging on the initial impedance matrix to obtain an average impedance matrix, and to establish the voltage-current relationship of the target line based on the average impedance matrix to obtain an initial relationship. The decoupling calculation module is used to decouple the initial relation to obtain a decoupling relation and a decoupling matrix, and to solve the fault boundary conditions of the target line based on the decoupling relation and the decoupling matrix to obtain the fault current of the target line. The data processing module is specifically used to obtain the self-inductance parameter of each loop in the initial impedance matrix, calculate the average value of the self-inductance parameter to obtain the average self-inductance parameter; obtain the phase-to-phase mutual inductance parameter of each loop in the initial impedance matrix, calculate the average value of the phase-to-phase mutual inductance parameter to obtain the average phase-to-phase mutual inductance parameter; obtain the line-to-line mutual inductance parameter of each loop in the initial impedance matrix, calculate the average line-to-line mutual inductance parameter to obtain the average line-to-line mutual inductance parameter; and replace the self-inductance parameter, phase-to-phase mutual inductance parameter, and line-to-line mutual inductance parameter in the initial impedance matrix with the average self-inductance parameter, the average phase-to-phase mutual inductance parameter, and the average line-to-line mutual inductance parameter, respectively, to obtain the average impedance matrix.

8. A storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

9. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

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