Cable fault component phase-mode transformation method, system, equipment and medium

Abstract

The invention belongs to the technical field of power system protection and control, and discloses a cable fault component phase-mode transformation method, system and device and a medium, and the method comprises the steps: collecting the three-phase conductive core current, the three-phase conductive core voltage and the three-phase metal shielding layer current of a cable; based on different types of current modulus transmission paths in the cable, establishing a current modulus model, substituting the three-phase conductive core current, the three-phase conductive core voltage and the three-phase metal shielding layer current into the current modulus model, and calculating a current modulus component corresponding to each current modulus transmission path; and analyzing the fault types of the cable in different fault modes based on the calculation result of the current modulus component. According to the method, on the basis of coupling characteristics among equivalent conductors of the cable, a calculation process capable of reflecting phase-mode transformation of fault components of all types of cable faults is built by combining mathematical characteristics of line parameters of the uniformly-transposed cable, and all fault types of the cable can be reflected by a single modulus.

Description

Technical Field

[0001] The invention belongs to the technical field of power system protection and control, and in particular to a method, system, equipment and medium for phase model transformation of cable fault components. Background Art

[0002] With the rapid advancement of urbanization, the proportion of overhead lines replaced by underground cables continues to increase, and the key position of underground cables in urban distribution networks has become increasingly prominent. During operation, underground cables may be threatened by various factors such as external force damage, overvoltage shocks, and animal attacks. At the same time, the cables themselves may also have insulation defects, which will cause the cables to fail during long-term energized operation. Sensitive detection and accurate distance measurement of cable faults are of great significance to ensure the safety and reliability of power supply.

[0003] The cable fault distance measurement requires extremely high accuracy, and traveling wave distance measurement based on time domain or frequency domain scanning is currently the only feasible technical means. The difficulty and key point of traveling wave distance measurement technology lies in the accurate identification of the wave head and the precise determination of the wave velocity. The cable structure is complex, and the electromagnetic coupling between the phase conductors and the metal shielding layer is complex, which will greatly affect the accuracy of the identification of the traveling wave head, thereby affecting the distance measurement accuracy, and even causing the distance measurement to fail.

[0004] Therefore, before fault location measurement, the three-phase electrical quantities must be decoupled and calculated, which is usually achieved through phase mode transformation. Phase mode transformation is a mathematical method used to simplify complex coupled line systems into independent, easy-to-analyze modules, thereby providing an accurate and reliable data basis for fault location measurement.

[0005] So far, there are two main types of phase mode transformation methods: frequency domain and time domain methods. The frequency domain phase mode transformation method is mainly a symmetrical component transformation method. Although its single modulus can comprehensively describe various fault types in the power system, the computational complexity of this method is greatly increased due to the involvement of complex number operations, which becomes its main limitation. The time domain phase mode transformation methods mainly include Clarke, Karenbauer and Wedpohl, etc. The elements in their transformation methods are all real numbers, the calculation is simple and convenient, and they have been widely used in power systems. However, this type of phase mode transformation method has the inherent limitation that a single modulus cannot reflect all fault types. In order to improve adaptability, it is usually necessary to adopt dual moduli or combine phase selection technology to ensure the effective identification of various fault types.

[0006] Therefore, how to provide a cable fault component phase model transformation method, system, equipment and medium. Summary of the invention

[0007] The embodiments of the present invention provide a method, system, device and medium for phase mode transformation of cable fault components to solve the above-mentioned technical problems existing in the prior art.

[0008] In order to have a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. This summary is not intended to be a general review, nor is it intended to identify key / important components or to delineate the scope of protection of these embodiments. Its only purpose is to present some concepts in a simple form as a preface to the detailed description that follows.

[0009] According to a first aspect of an embodiment of the present invention, a method for phase mode transformation of a cable fault component is provided.

[0010] In one embodiment, the cable fault component phase mode transformation method includes:

[0011] According to the distribution of the cable conductor, metal shielding layer and three-phase line of the cable to be monitored, the three-phase conductor current, three-phase conductor voltage and three-phase metal shielding layer current of the cable are collected;

[0012] Based on different types of current modulus transmission paths in the cable, a current modulus model is established, the three-phase core current, the three-phase core voltage and the three-phase metal shielding layer current are substituted into the current modulus model, and the current modulus components corresponding to each current modulus transmission path are calculated;

[0013] Based on the calculation results of the current modulus component, the fault types of the cable under different fault modes are analyzed.

[0014] In one embodiment, the cables are arranged in a herringbone shape, and before collecting the three-phase core current, three-phase core voltage and three-phase metal shielding layer current of the cables, it also includes: setting the sampling frequency of the cables.

[0015] In one embodiment, the current modulus model is established based on different types of current modulus transmission paths in the cable, the three-phase core current, the three-phase core voltage and the three-phase metal shielding layer current are substituted into the current modulus model, and the current modulus components corresponding to each current modulus transmission path are calculated, including:

[0016] According to the combination of the outflow direction and the return direction of the current propagation in the cable, multiple types of current modulus transmission paths and the path current ratio of the current in each of the current modulus transmission paths are set;

[0017] Based on the current modulus transmission paths and their respective path current ratios, a calculation formula for the current modulus component corresponding to each current modulus transmission path is established, and a current modulus model is formed by integrating all the formulas;

[0018] The three-phase core current, three-phase core voltage and three-phase metal shielding layer current collected in real time are input into the current modulus model, and the current modulus components corresponding to each current modulus transmission path are calculated.

[0019] In one embodiment, the current modulus transmission path includes: each phase metal shielding layer flows out and returns through the ground, a single-phase metal shielding layer flows out and returns through the other two-phase metal shielding layers, each phase conductor core flows out and returns through the corresponding metal shielding layer, an edge phase conductor core flows out and returns through other edge phase conductor cores, and an intermediate phase conductor core flows out and returns through both side edge phase conductor cores.

[0020] In one embodiment, the path current ratio represents the current proportion of the current in the cable in each outflow direction and return direction. In the same current modulus transmission path, the sum of the current proportions in the outflow direction is equal to the sum of the current proportions in the return direction.

[0021] In one embodiment, the calculation formula of the current modulus model is:

[0022]

[0023] Where i1~i6 represent the current modulus components corresponding to different current modulus transmission paths; i a Indicates the current of the conductor core of phase A; i b Indicates the current of the conductor core of phase B; i c Indicates the C phase conductor current; u a Indicates the A phase conductor voltage; u b Indicates the voltage of the conductor core of phase B; u c Indicates the C phase conductor voltage; i A Represents the metal shielding layer current of phase A; i B Represents the metal shielding layer current of phase B; i C Indicates the C-phase metal shield current.

[0024] In one embodiment, the fault types existing in the cable include: ground fault, metal sheath fault, single-phase ground fault and total fault state.

[0025] According to a second aspect of an embodiment of the present invention, a cable fault component phase model transformation system is provided.

[0026] In one embodiment, the cable fault component phase conversion system comprises:

[0027] The cable acquisition module is used to collect the three-phase core current, three-phase core voltage and three-phase metal shielding layer current of the cable according to the core, metal shielding layer and three-phase line distribution of the cable to be monitored;

[0028] A component calculation module, used to establish a current modulus model based on different types of current modulus transmission paths in the cable, substitute the three-phase core current, the three-phase core voltage and the three-phase metal shielding layer current into the current modulus model, and calculate the current modulus components corresponding to each current modulus transmission path;

[0029] The fault analysis module is used to analyze the fault type of the cable under different fault modes based on the calculation result of the current modulus component.

[0030] In one embodiment, the cables are arranged in a herringbone shape, and before collecting the three-phase core current, three-phase core voltage and three-phase metal shielding layer current of the cables, it also includes: setting the sampling frequency of the cables.

[0031] In one embodiment, the component calculation module includes: a path definition module, a model definition module and a model calculation module, wherein:

[0032] The path definition module is used to set multiple types of current modulus transmission paths and path current ratios of the current in each of the current modulus transmission paths according to a combination of an outflow direction and a return direction of current propagation in the cable;

[0033] The model definition module is used to establish a calculation formula for the current modulus component corresponding to each current modulus transmission path based on the current modulus transmission paths and the respective path current ratios, and to form a current modulus model by integrating all the formulas;

[0034] The model calculation module is used to input the three-phase core current, three-phase core voltage and three-phase metal shielding layer current collected in real time into the current modulus model, and calculate the current modulus components corresponding to each current modulus transmission path.

[0035] In one embodiment, the current modulus transmission path includes: each phase metal shielding layer flows out and returns through the ground, a single-phase metal shielding layer flows out and returns through the other two-phase metal shielding layers, each phase conductor core flows out and returns through the corresponding metal shielding layer, an edge phase conductor core flows out and returns through other edge phase conductor cores, and an intermediate phase conductor core flows out and returns through both side edge phase conductor cores.

[0036] In one embodiment, the path current ratio represents the current proportion of the current in the cable in each outflow direction and return direction. In the same current modulus transmission path, the sum of the current proportions in the outflow direction is equal to the sum of the current proportions in the return direction.

[0037] In one embodiment, the calculation formula of the current modulus model is:

[0038]

[0039] Where i1~i6 represent the current modulus components corresponding to different current modulus transmission paths; i a Indicates the current of the conductor core of phase A; i b Indicates the current of the conductor core of phase B; i c Indicates the C phase conductor current; u a Indicates the A phase conductor voltage; u b Indicates the voltage of the conductor core of phase B; u c Indicates the C phase conductor voltage; i A Represents the metal shielding layer current of phase A; i B Represents the metal shielding layer current of phase B; i C Indicates the C-phase metal shield current.

[0040] In one embodiment, the fault types existing in the cable include: ground fault, metal sheath fault, single-phase ground fault and total fault state.

[0041] According to a third aspect of an embodiment of the present invention, a computer device is provided.

[0042] In some embodiments, the computer device includes a memory and a processor, the memory stores a computer program, and the processor implements the steps of the above method when executing the computer program.

[0043] According to a fourth aspect of embodiments of the present invention, a computer-readable storage medium is provided.

[0044] In one embodiment, the computer-readable storage medium stores a computer program, and the computer program implements the steps of the above method when executed by a processor.

[0045] The technical solution provided by the embodiment of the present invention may include the following beneficial effects: In view of the problem that the fault component extracted by the existing phase-mode transformation cannot reflect all fault types, the present invention is based on the coupling characteristics between the equivalent conductors of the cable, combined with the mathematical characteristics of the uniformly transposed cable line parameters, to build a calculation process for the phase-mode transformation of the fault component that can reflect all types of cable faults, and separate the coupled current signal into six different moduli, each of which can characterize different fault characteristics of the cable, and is suitable for fault detection and fault ranging under various fault conditions. The process is simple to calculate, has high decoupling accuracy, and a single modulus can reflect all fault types of the cable, which has important practical value for subsequent fault protection, control and ranging technology.

[0046] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0048] Figure 1 is a flow chart showing a method for phase model transformation of cable fault components according to an exemplary embodiment;

[0049] Figure 2 is a structural schematic diagram of a cable fault component phase model transformation system according to an exemplary embodiment;

[0050] Figure 3 is a structural schematic diagram of a computer device according to an exemplary embodiment;

[0051] Figure 4 is a schematic diagram of an underground herringbone-shaped cable structure according to an exemplary embodiment;

[0052] Figure 5 is a schematic diagram of a current modulus transmission path of a cable under modulus 1 condition according to an exemplary embodiment;

[0053] Figure 6 is a schematic diagram of a current modulus transmission path of a cable under modulus 2 conditions according to an exemplary embodiment;

[0054] Figure 7 is a schematic diagram of a current modulus transmission path of a cable under modulus 3 conditions according to an exemplary embodiment;

[0055] Figure 8 is a schematic diagram of a current modulus transmission path of a cable under modulus 4 conditions according to an exemplary embodiment;

[0056] Fig. 9 is a schematic diagram of a current modulus transmission path of a cable under a modulus 5 condition according to an exemplary embodiment;

[0057] Fig.10 is a schematic diagram of a current modulus transmission path of a cable under modulus 6 conditions according to an exemplary embodiment;

[0058] Fig.11 is a fault current waveform diagram before decoupling according to an exemplary embodiment;

[0059] Fig.12 is a waveform diagram of six current modulus components according to an exemplary embodiment. DETAILED DESCRIPTION

[0060] The following description and accompanying drawings fully illustrate the specific embodiments of this article so that those skilled in the art can practice them. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. The scope of the embodiments of this article includes the entire scope of the claims, as well as all available equivalents of the claims. Herein, the terms "first", "second", etc. are only used to distinguish one element from another, without requiring or implying any actual relationship or order between these elements. In fact, the first element can also be called the second element, and vice versa. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that the structure, device or equipment including a series of elements includes not only those elements, but also other elements that are not explicitly listed, or also include elements inherent to such structure, device or equipment. In the absence of more restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the structure, device or equipment including the elements. Each embodiment is described in a progressive manner herein, and each embodiment focuses on the differences from other embodiments, and the same and similar parts between the embodiments can be referred to each other.

[0061] The terms "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. in this document indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing this document and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of this document, unless otherwise specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a mechanical connection or an electrical connection, it can also be the internal communication of two elements, it can be a direct connection, or it can be an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0062] As used herein, the term "plurality" means two or more than two, unless otherwise specified.

[0063] In this document, the character " / " indicates that the preceding and following objects are in an "or" relationship. For example, A / B means: A or B.

[0064] In this article, the term "and / or" is a description of the association relationship between objects, indicating that three relationships may exist. For example, A and / or B means: A or B, or, A and B.

[0065] It should be understood that, although the various steps in the flow chart are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear description in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the figure may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these sub-steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0066] Each module in the device or system of the present application can be implemented in whole or in part by software, hardware, or a combination thereof. The above modules can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in a computer device in the form of software, so that the processor can call and execute operations corresponding to the above modules.

[0067] In the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0068] Figure 1 An embodiment of a cable fault component phase mode transformation method of the present invention is shown.

[0069] In this optional embodiment, the cable fault component phase mode transformation method includes:

[0070] Step S101, collecting the three-phase core current, three-phase core voltage and three-phase metal shielding layer current of the cable according to the core, metal shielding layer and three-phase line distribution of the cable to be monitored;

[0071] Step S103, based on different types of current modulus transmission paths in the cable, a current modulus model is established, the three-phase core current, the three-phase core voltage and the three-phase metal shielding layer current are substituted into the current modulus model, and the current modulus components corresponding to each current modulus transmission path are calculated;

[0072] Step S105: Analyze the fault types of the cable under different fault modes based on the calculation results of the current modulus component.

[0073] In this optional embodiment, the cables are arranged in a herringbone shape, and before collecting the three-phase core current, three-phase core voltage and three-phase metal shielding layer current of the cable, it also includes: setting the sampling frequency of the cable.

[0074] In this optional embodiment, a current modulus model is established based on the different types of current modulus transmission paths in the cable, and the three-phase core current, three-phase core voltage and three-phase metal shielding layer current are substituted into the current modulus model to calculate the current modulus components corresponding to each current modulus transmission path. According to the combination of the outflow direction and the return direction of the current propagation in the cable, multiple types of current modulus transmission paths and the path current ratio of the current in each of the current modulus transmission paths can be set; based on the current modulus transmission paths and their respective path current ratios, a calculation formula for the current modulus components corresponding to each current modulus transmission path is established, and a current modulus model is formed by integrating all the formulas; the three-phase core current, three-phase core voltage and three-phase metal shielding layer current collected in real time are input into the current modulus model, and the current modulus components corresponding to each current modulus transmission path are calculated.

[0075] In this optional embodiment, the current modulus transmission path includes: each phase metal shielding layer flows out and returns through the ground, a single-phase metal shielding layer flows out and returns through the other two-phase metal shielding layers, each phase conductor core flows out and returns through the corresponding metal shielding layer, an edge phase conductor core flows out and returns through other edge phase conductor cores, and an intermediate phase conductor core flows out and returns through both side edge phase conductor cores.

[0076] In this optional embodiment, the path current ratio represents the current proportion in each outflow direction and return direction of the cable. In the same current modulus transmission path, the sum of the current proportions in the outflow direction is equal to the sum of the current proportions in the return direction.

[0077] In this optional embodiment, the calculation formula of the current modulus model is:

[0078]

[0079] Where i1~i6 represent the current modulus components corresponding to different current modulus transmission paths; i a Indicates the current of the conductor core of phase A; i b Indicates the current of the conductor core of phase B; i c Indicates the C phase conductor current; u a Indicates the A phase conductor voltage; u b Indicates the voltage of the conductor core of phase B; u c Indicates the C phase conductor voltage; i A Represents the metal shielding layer current of phase A; i B Represents the metal shielding layer current of phase B; i C Indicates the C-phase metal shield current.

[0080] In this optional embodiment, the types of faults existing in the cable include: ground fault, metal sheath fault, single-phase ground fault and total fault state.

[0081] Figure 2 An embodiment of a cable fault component phase model transformation system of the present invention is shown.

[0082] In this optional embodiment, the cable fault component phase model transformation system includes:

[0083] The cable collection module 201 is used to collect the three-phase core current, three-phase core voltage and three-phase metal shielding layer current of the cable according to the core, metal shielding layer and three-phase line distribution of the cable to be monitored;

[0084] The component calculation module 203 is used to establish a current modulus model based on different types of current modulus transmission paths in the cable, substitute the three-phase core current, the three-phase core voltage and the three-phase metal shielding layer current into the current modulus model, and calculate the current modulus components corresponding to each current modulus transmission path;

[0085] The fault analysis module 205 is used to analyze the fault type of the cable under different fault modes based on the calculation result of the current modulus component.

[0086] In this optional embodiment, the cables are arranged in a herringbone shape, and before collecting the three-phase core current, three-phase core voltage and three-phase metal shielding layer current of the cable, it also includes: setting the sampling frequency of the cable.

[0087] In this optional embodiment, the component calculation module 203 includes: a path definition module (not shown in the figure), a model definition module (not shown in the figure) and a model calculation module (not shown in the figure), wherein the path definition module is used to set multiple types of current modulus transmission paths and the path current ratio of the current in each of the current modulus transmission paths according to the combination of the outflow direction and the return direction of the current propagation in the cable; the model definition module is used to establish a calculation formula for the current modulus component corresponding to each current modulus transmission path based on the current modulus transmission path and the respective path current ratios, and form a current modulus model by integrating all formulas; the model calculation module is used to input the three-phase core current, three-phase core voltage and three-phase metal shielding layer current collected in real time into the current modulus model, and calculate the current modulus component corresponding to each current modulus transmission path.

[0088] In this optional embodiment, the current modulus transmission path includes: each phase metal shielding layer flows out and returns through the ground, a single-phase metal shielding layer flows out and returns through the other two-phase metal shielding layers, each phase conductor core flows out and returns through the corresponding metal shielding layer, an edge phase conductor core flows out and returns through other edge phase conductor cores, and an intermediate phase conductor core flows out and returns through both side edge phase conductor cores.

[0089] In this optional embodiment, the path current ratio represents the current proportion in each outflow direction and return direction of the cable. In the same current modulus transmission path, the sum of the current proportions in the outflow direction is equal to the sum of the current proportions in the return direction.

[0090] In this optional embodiment, the calculation formula of the current modulus model is:

[0091]

[0092] Where i1~i6 represent the current modulus components corresponding to different current modulus transmission paths; i a Indicates the current of the conductor core of phase A; i b Indicates the current of the conductor core of phase B; i c Indicates the C phase conductor current; u a Indicates the A phase conductor voltage; u b Indicates the voltage of the conductor core of phase B; u c Indicates the C phase conductor voltage; i A Represents the metal shielding layer current of phase A; i B Represents the metal shielding layer current of phase B; i C Indicates the C-phase metal shield current.

[0093] In this optional embodiment, the types of faults existing in the cable include: ground fault, metal sheath fault, single-phase ground fault and total fault state.

[0094] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0095] Step 1) Figure 3 As shown, the cables are arranged in a triangle shape, and the three-phase core current i of the cable is collected. a ,i b ,i c , three-phase conductor core voltage u a ,u b ,u c , the three-phase metal shielding layer current i of the cable A ,i B ,i C ; Sampling frequency 10kHz, as shown in Table 1;

[0096] Table 1: Current of three-phase conductor core and metal shield

[0097]

[0098] The fault current waveform before decoupling is as follows: Fig.11 As shown, it can be seen that the various modes are cross-coupled with each other, resulting in serious mutual interference, which is not conducive to traveling wave ranging.

[0099] Step 2) The current modulus components i1 to i6 of the cable are calculated by the following current modulus model calculation formula, as shown in Table 2.

[0100] Table 2: Current modulus i1~i6

[0101]

[0102] Fig.12 The six components calculated by the patented fault component phase mode transformation method are clearly shown in the figure. It can be seen that the mutually coupled signals are finely separated into six moduli with obvious fault characteristics. Each modulus can reflect different characteristics of the cable fault. By decomposing the cable fault signal into multiple components, the fault type and location can be identified more accurately, improving the efficiency of fault detection and location.

[0103] Step 3) Selection and use of current modulus components:

[0104] The schematic diagram of each current modulus transmission path of the cable is as follows Figure 5-Figure 10 shown.

[0105] like Figure 5 As shown in Figure 1, modulus 1 describes the current flowing out of the metal shielding layer of each phase and returning to the ground. Since it is transmitted through the ground, its propagation speed is the slowest and there is significant attenuation, which is suitable for ground fault detection.

[0106] like Figure 6-Figure 7 As shown in Figure 2, modulus 2 and modulus 3 describe the situation where the current flows out of the metal shielding layer of one phase and returns through the metal shielding layers of the other two phases. These two moduli are less affected by frequency and are suitable for fault location related to metal sheaths, such as single-phase metal sheath grounding and two-phase metal sheath short-circuit grounding.

[0107] like Figure 8 As shown, modulus 4 shows that the current flows out from each phase conductor and returns from the corresponding metal shielding layer, which is mainly used to detect single-phase grounding faults.

[0108] like Fig. 9 As shown, the modulus 5 describes the situation where the current flows out of a side phase conductor and returns from the middle phase and the other side phase conductor.

[0109] like Fig.10 As shown, modulus 6 is characterized by injecting current into the middle phase conductor and returning from the two edge phase conductors, and its characteristics are similar to modulus 5. These two moduli can characterize the full fault state and can be used for detection and distance measurement of the full fault state.

[0110] Specifically, each component represents the characteristic response of the cable under different fault modes, which facilitates targeted fault analysis.

[0111] In one embodiment, a computer device is provided. The computer device may be a server, and its internal structure diagram may be as follows: Figure 3 As shown. The computer device includes a processor, a memory and a network interface connected through a system bus. Among them, the processor of the computer device is used 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 the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store static information and dynamic information data. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, the steps in the above method embodiment are implemented.

[0112] Those skilled in the art will understand that Figure 3 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present invention, and does not constitute a limitation on the computer device to which the solution of the present invention is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0113] In addition, the present invention also provides a computer device, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above method embodiment when executing the computer program.

[0114] In addition, the present invention further provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps in the above method embodiment are implemented.

[0115] 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, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided by the present invention can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory, etc. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0116] The present invention is not limited to the structures which have been described above and shown in the drawings, and various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A method for phase model transformation of cable fault components, characterized in that: include: According to the distribution of the cable conductor, metal shielding layer and three-phase line of the cable to be monitored, the three-phase conductor current, three-phase conductor voltage and three-phase metal shielding layer current of the cable are collected; Based on different types of current modulus transmission paths in the cable, a current modulus model is established, the three-phase core current, the three-phase core voltage and the three-phase metal shielding layer current are substituted into the current modulus model, and the current modulus components corresponding to each current modulus transmission path are calculated; Based on the calculation results of the current modulus component, the fault types of the cable under different fault modes are analyzed.

2. The cable fault component phase mode transformation method according to claim 1, characterized in that: The cables are arranged in a herringbone shape, and before collecting the three-phase core current, the three-phase core voltage and the three-phase metal shielding layer current of the cables, the method also includes: setting the sampling frequency of the cables.

3. The cable fault component phase mode transformation method according to claim 1, characterized in that: The current modulus model is established based on different types of current modulus transmission paths in the cable, the three-phase core current, the three-phase core voltage and the three-phase metal shielding layer current are substituted into the current modulus model, and the current modulus components corresponding to each current modulus transmission path are calculated, including: According to the combination of the outflow direction and the return direction of the current propagation in the cable, multiple types of current modulus transmission paths and the path current ratio of the current in each of the current modulus transmission paths are set; Based on the current modulus transmission paths and their respective path current ratios, a calculation formula for the current modulus component corresponding to each current modulus transmission path is established, and a current modulus model is formed by integrating all the formulas; The three-phase core current, three-phase core voltage and three-phase metal shielding layer current collected in real time are input into the current modulus model, and the current modulus components corresponding to each current modulus transmission path are calculated.

4. The cable fault component phase mode transformation method according to claim 3, characterized in that: The current modulus transmission path includes: each phase metal shielding layer flows out and returns through the ground, a single-phase metal shielding layer flows out and returns through the other two-phase metal shielding layers, each phase conductor core flows out and returns through the corresponding metal shielding layer, an edge phase conductor core flows out and returns through other edge phase conductor cores, and an intermediate phase conductor core flows out and returns through both side edge phase conductor cores.

5. The cable fault component phase mode transformation method according to claim 3, characterized in that: The path current ratio represents the current ratio of the current in the cable in each outflow direction and return direction. In the same current modulus transmission path, the sum of the current ratios in the outflow direction is equal to the sum of the current ratios in the return direction.

6. The cable fault component phase mode transformation method according to claim 3, characterized in that: The calculation formula of the current modulus model is: Where i1~i6 represent the current modulus components corresponding to different current modulus transmission paths; i a Indicates the current of the conductor core of phase A; i b Indicates the current of the conductor core of phase B; i c Indicates the C phase conductor current; u a Indicates the A phase conductor voltage; u b Indicates the B phase conductor voltage; u c Indicates the C phase conductor voltage; i A Represents the metal shielding layer current of phase A; i B Represents the metal shielding layer current of phase B; i C Indicates the C-phase metal shield current.

7. The cable fault component phase mode transformation method according to claim 1, characterized in that: The fault types existing in the cable include: ground fault, metal sheath fault, single-phase ground fault and total fault state.

8. A cable fault component phase conversion system, characterized in that: include: The cable acquisition module is used to collect the three-phase core current, three-phase core voltage and three-phase metal shielding layer current of the cable according to the core, metal shielding layer and three-phase line distribution of the cable to be monitored; A component calculation module, used to establish a current modulus model based on different types of current modulus transmission paths in the cable, substitute the three-phase core current, the three-phase core voltage and the three-phase metal shielding layer current into the current modulus model, and calculate the current modulus components corresponding to each current modulus transmission path; The fault analysis module is used to analyze the fault type of the cable under different fault modes based on the calculation result of the current modulus component.

9. The cable fault component phase model conversion system according to claim 8, characterized in that: The cables are arranged in a herringbone shape, and before collecting the three-phase core current, the three-phase core voltage and the three-phase metal shielding layer current of the cables, the method also includes: setting the sampling frequency of the cables.

10. The cable fault component phase mode conversion system according to claim 8, characterized in that: The component calculation module includes: a path definition module, a model definition module and a model calculation module, wherein: The path definition module is used to set multiple types of current modulus transmission paths and path current ratios of the current in each of the current modulus transmission paths according to a combination of an outflow direction and a return direction of current propagation in the cable; The model definition module is used to establish a calculation formula for the current modulus component corresponding to each current modulus transmission path based on the current modulus transmission paths and the respective path current ratios, and to form a current modulus model by integrating all the formulas; The model calculation module is used to input the three-phase core current, three-phase core voltage and three-phase metal shielding layer current collected in real time into the current modulus model, and calculate the current modulus components corresponding to each current modulus transmission path.

11. The cable fault component phase conversion system according to claim 10, characterized in that: The current modulus transmission path includes: each phase metal shielding layer flows out and returns through the ground, a single-phase metal shielding layer flows out and returns through the other two-phase metal shielding layers, each phase conductor core flows out and returns through the corresponding metal shielding layer, an edge phase conductor core flows out and returns through other edge phase conductor cores, and an intermediate phase conductor core flows out and returns through both side edge phase conductor cores.

12. The cable fault component phase mode conversion system according to claim 10, characterized in that: The path current ratio represents the current ratio of the current in the cable in each outflow direction and return direction. In the same current modulus transmission path, the sum of the current ratios in the outflow direction is equal to the sum of the current ratios in the return direction.

13. The cable fault component phase model conversion system according to claim 10, characterized in that: The calculation formula of the current modulus model is: Where i1~i6 represent the current modulus components corresponding to different current modulus transmission paths; i a Indicates the current of the conductor core of phase A; i b Indicates the current of the conductor core of phase B; i c Indicates the C phase conductor current; u a Indicates the A phase conductor voltage; u b Indicates the B phase conductor voltage; u c Indicates the C phase conductor voltage; i A Represents the metal shielding layer current of phase A; i B Represents the metal shielding layer current of phase B; i C Indicates the C-phase metal shield current.

14. The cable fault component phase conversion system according to claim 8, characterized in that: The fault types existing in the cable include: ground fault, metal sheath fault, single-phase ground fault and total fault state.

15. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

16. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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