Simulation method and device for power cable fault location and medium

Abstract

The invention discloses a simulation method and device for power cable fault positioning and a medium, and the method comprises the steps: collecting a power cable fault instance, and building a fault model for simulating a plurality of power cable fault types according to the power cable fault instance; determining a training stage where the user is located, and selecting a target power cable fault type matched with the training stage from a plurality of power cable fault types corresponding to the fault model; loading the fault model and a preset electromagnetic interference model to generate a simulation training scene for the fault type of the target power cable, and receiving an operation instruction sent by a user through interaction equipment in the simulation training scene; and converting the operation instruction into an operation parameter corresponding to the to-be-positioned power cable, and positioning a fault existing in the power cable according to the operation parameter and a power cable parameter corresponding to the power cable to obtain corresponding fault information, thereby realizing fault simulation positioning of the power cable.

Description

Technical Field

[0001] The present application relates to the field of electric power technology, and in particular to a simulation method, device and medium for locating power cable faults. Background Art

[0002] In modern power systems, 10kV cables, as an important part of power transmission, are widely used in urban distribution networks, industrial production and other fields. However, due to the long-term operation of cables in complex environmental conditions, various faults are prone to occur, resulting in power transmission interruptions or safety accidents. Therefore, accurately and quickly locating the cable fault point is of great significance for timely repairing the fault and restoring power supply. Power cable fault location technology is a key skill that power workers must master. In order to improve the fault location skills of the staff, it is also very necessary to conduct regular detection skills training for them.

[0003] In the traditional on-site training process, operators need to carry high-voltage pulse generators, oscilloscopes, resistor dividers and other equipment, which requires a lot of equipment handling and connection work. The operation process is cumbersome and complicated, consuming a lot of time and manpower, and it is difficult to be widely used in training. Secondly, the high-voltage pulses applied in on-site testing are dangerous and pose a threat to the safety of operators. In addition, factors such as electromagnetic interference and noise in the on-site environment will interfere with the test signal and affect the accuracy of fault location. The existing simulation training method usually provides training content for operators based on a virtual simulation system with a computer graphical interface. It cannot allow users to truly feel the environment and operation experience of being in the actual test site, and it is difficult to effectively improve the user's actual operation skills. Summary of the invention

[0004] In order to solve the above problems, the present application proposes a simulation method for power cable fault location, which is applied to a preset virtual simulation system, including:

[0005] Collecting power cable fault instances, and establishing a fault model for simulating various power cable fault types according to the power cable fault instances;

[0006] Determine the training stage of the user, and select a target power cable fault type that matches the training stage from a plurality of power cable fault types corresponding to the fault model;

[0007] Loading the fault model and the preset electromagnetic interference model to generate a simulation training scenario for the target power cable fault type, and receiving an operation instruction sent by the user through an interactive device in the simulation training scenario;

[0008] The operation instruction is converted into operation parameters corresponding to the power cable to be located, and the fault existing in the power cable is located according to the operation parameters and the power cable parameters corresponding to the power cable to obtain corresponding fault information, thereby realizing fault simulation positioning of the power cable.

[0009] In one implementation of the present application, determining the training stage of the user specifically includes:

[0010] Acquire historical training data of the user, and determine the power cable fault type and its corresponding operation evaluation value that the user participated in training in each training process according to the historical training data;

[0011] Selecting a specified power cable fault type whose operation evaluation value is less than a preset value, and determining, for the specified power cable fault type, an increase in the corresponding operation evaluation value of the specified power cable fault type during different training processes;

[0012] According to the growth amount, determine the training stage of the user; wherein the training stage includes at least three training stages, namely, an initial training stage in which the growth amount is greater than a first growth amount, a platform training stage in which the growth amount is less than the first growth amount and greater than a second growth amount, and a convergence training stage in which the growth amount is less than the second growth amount.

[0013] In one implementation of the present application, selecting a target power cable fault type that matches the training stage from a plurality of power cable fault types corresponding to the fault model specifically includes:

[0014] Obtaining a standard operation evaluation value corresponding to the training stage; wherein the standard operation evaluation value is positively correlated with the growth amount;

[0015] From the multiple power cable fault types corresponding to the fault model, a power cable fault type corresponding to an operation evaluation value lower than the standard operation evaluation value is selected as a target power cable fault type matching the training stage.

[0016] In one implementation of the present application, determining the training stage of the user according to the growth amount specifically includes:

[0017] Determine whether there is any specified power cable fault type whose corresponding growth amount is greater than the first growth amount, and if so, determine that the training stage of the user is the initial training stage;

[0018] If not, when the growth amount corresponding to any specified power cable fault type is less than the first growth amount and greater than the second growth amount, it is determined that the training stage of the user is the platform training stage; otherwise, it is determined that the training stage of the user is the convergence training stage.

[0019] In one implementation of the present application, according to the power cable fault instance, a fault model for simulating multiple power cable fault types is established, specifically including:

[0020] Extracting cable parameters corresponding to the power cable from the power cable fault instance;

[0021] For the power cable to be located, abstract it into a corresponding uniform transmission line model, and determine the electrical transmission characteristics corresponding to the power cable based on the uniform transmission line model;

[0022] According to the electrical transmission characteristics, a fault impedance model for simulating various power cable fault types is constructed; wherein the fault impedance model can be expressed as:

[0023]

[0024] Among them, Γ f is the reflection coefficient at the end of the cable. If the end of the cable is open (Z f =∞), then Γ f =1; Z f The impedance at the end of the cable, Z 0 represents the characteristic impedance of the fault location, e -2γ(l-x) An exponential term representing the signal propagation related to the cable;

[0025] According to the fault impedance model and cable parameters of different types of power cables, fault models corresponding to different power cable fault instances are constructed.

[0026] In one implementation of the present application, after establishing a fault model for simulating multiple types of power cable faults according to the power cable fault instance, the method further includes:

[0027] Based on the fault model, a simulation training is performed on the power cable fault instance to obtain corresponding fault parameters;

[0028] Comparing the fault parameters with actual fault parameters corresponding to the power cable fault instance, so as to determine the type of cable parameters to be adjusted according to the comparison result; wherein the cable parameter type includes at least conductor parameters, insulation parameters, cable structure parameters, electrical performance parameters, and signal propagation speed;

[0029] The cable parameters included in the cable parameter type are adjusted, and the fault model is updated using the adjusted cable parameters until the difference between the fault parameter and the actual fault parameter satisfies a preset difference range.

[0030] In an implementation of the present application, locating a fault in the power cable according to the operating parameter and a power cable parameter corresponding to the power cable to obtain corresponding fault information specifically includes:

[0031] Determining whether the operating parameter matches a target operating parameter corresponding to the target power cable fault type when performing fault location;

[0032] If yes, collect the reflected wave corresponding to the pulse signal sent by the power cable in response to the operation instruction, and extract the fault characteristics in the reflected wave by wavelet transform; wherein the fault characteristics include at least one or more of the following: signal arrival time, reflected wave amplitude, reflected wave frequency;

[0033] According to the fault feature, the distance between the fault point in the power cable and the measurement point corresponding to the operation instruction is calculated to obtain fault information corresponding to the power cable.

[0034] In one implementation of the present application, after extracting the fault feature in the reflected wave, the method further includes:

[0035] Determine, according to the fault model, fault resistance information existing in the power cable, and determine, according to the fault resistance information, a delay time caused by the fault resistance information to the reflected wave;

[0036] The signal arrival time is corrected according to the delay time, so that the sum of the delay time and the signal arrival time is used as the corrected signal arrival time.

[0037] The embodiment of the present application provides a simulation device for locating a power cable fault, which is applied to a preset virtual simulation system, and the device includes:

[0038] at least one processor;

[0039] and, a memory communicatively coupled to the at least one processor;

[0040] The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute a simulation method for power cable fault location as described in any one of the above items.

[0041] The embodiment of the present application provides a non-volatile computer storage medium storing computer executable instructions, which is applied to a preset virtual simulation system, wherein the computer executable instructions are configured as follows:

[0042] A simulation method for power cable fault location as described in any one of the above items.

[0043] The simulation method for power cable fault location proposed in this application can bring the following results:

[0044] Beneficial effects:

[0045] By building a power cable fault model and simulating multiple fault types in a computer environment, the tedious process of carrying a large amount of physical equipment in traditional training is eliminated. Operators do not need to move and connect various high-voltage equipment, which significantly reduces the preparation time and cost before training.

[0046] By simulating training scenarios, factors that may affect the accuracy of fault location in actual environments, such as electromagnetic interference and noise, are taken into account, and corresponding interference models are built in. This allows operators to train in a close-to-real working environment, thereby improving their accuracy in fault location in complex environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0048] Figure 1 A schematic diagram of a flow chart of a simulation method for power cable fault location provided in an embodiment of the present application;

[0049] Figure 2 A schematic diagram of the structure of a simulation device for locating power cable faults provided in an embodiment of the present application. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be clearly and completely described below in combination with the specific embodiments of the present application and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

[0051] The embodiment of the present application provides a virtual simulation system, which includes VR devices, other interactive input devices such as handles, and a computer host with powerful computing power. The virtual simulation system includes a data processing module, a scene simulation module, an interactive control module, and a result display module. Among them, the data processing module is responsible for accurately processing fault model data, user operation data, and various environmental parameter data; the scene simulation module uses advanced three-dimensional modeling technology and physical simulation algorithms to generate highly realistic simulation training scenes in real time according to data processing results, including cable laying environment, test instruments and equipment, fault phenomena, etc.; the interactive control module receives the operation instructions issued by the user through handles, gestures or other input devices through high-precision sensors and advanced signal reception and conversion technology, and quickly and accurately converts them into system-recognizable signals to achieve natural interaction between users and virtual scenes; the result display module uses high-definition display technology and intuitive data presentation methods to display test results, fault location information, operation prompts, etc. in a clear and easy-to-understand form in the VR device, so that users can understand the operation feedback and simulation results in a timely manner.

[0052] The technical solutions provided by various embodiments of the present application are described in detail below in conjunction with the accompanying drawings.

[0053] like Figure 1 As shown, a simulation method for power cable fault location provided in an embodiment of the present application is applied to a preset virtual simulation system, including:

[0054] S101: Collect power cable fault instances, and establish a fault model for simulating various power cable fault types according to the power cable fault instances.

[0055] From the historical power cable fault data, the fault instances of 10kV power cables are collected. Each power cable fault instance includes cable parameters, fault location information, fault parameters and other information. The role of the power cable fault instance is to analyze the fault characteristics corresponding to different types of faults, so as to establish a fault model that can simulate various types of power cable faults. In the fault model, it is necessary to fully consider the size and variation range of the fault resistance, the distribution possibility of the fault location on the cable line, the different types of grounding methods (such as single-point grounding, multi-point grounding, etc.), and the formation and development process of the fault. The influence of factors such as the generation and propagation of fault signals. By loading the fault model, the virtual simulation system can simulate different types of power cable faults. Based on these power cable faults, the user can control the corresponding interactive equipment to simulate the fault detection operation, so as to obtain the corresponding fault location results and fault parameters.

[0056] The cable can be abstracted as a uniform transmission line model. Based on the uniform transmission line model, the power cable transmission characteristics can be determined. For a power cable with a length of x, its corresponding power cable transmission characteristics (voltage and current) can be expressed as:

[0057]

[0058] Where V(x,t) represents the voltage of the power cable at position x at time t; is the characteristic impedance, is the signal propagation speed, R f is the fault resistance, x 0 is the fault location, V 1 and I(ξ,t) are the related voltage and current parameters, j represents the imaginary unit, ω is the angular frequency, and ξ represents the initial phase;

[0059]

[0060] Where I(x,t) represents the current of the power cable at position x and time t; I 1 and V(ξ,t) are the relevant voltage and current parameters.

[0061] Through the above equations, the propagation and change of voltage and current in the power cable can be described, so as to simulate the generation and propagation of fault signals, and then construct a fault impedance model for simulating various power cable fault types. The fault impedance model can be expressed as:

[0062]

[0063] Among them, Γ f is the reflection coefficient at the end of the cable. If the end of the cable is open (Z f =∞), then Γ f =1; Z f The impedance at the end of the cable, Z 0 represents the characteristic impedance of the fault location, e -2γ(l-x) An exponential term representing the signal propagation related to the cable;

[0064] It should be noted that the existence of a fault point will cause changes in the signal transmission characteristics at that point. Common cable fault types can be divided into open circuit, short circuit, high resistance, and low resistance faults. For open circuit faults, according to the fault impedance model, when the end of the cable is open, Z f =∞, then Z l =-Z c , so by adjusting Z f For short-circuit faults, the fault resistance R fFor high-resistance faults, adjust the fault resistance R according to the actual resistance size and variation range of the high-resistance fault. f For low resistance fault, similar to high resistance fault, by setting appropriate lower fault resistance R f value to simulate a low resistance fault.

[0065] It can be seen that by adjusting the fault parameters, different types of power cable faults can be simulated. However, due to the differences in characteristics between power cables and the different types of power cables used in different usage scenarios, it is also necessary to build fault models corresponding to different power cable fault instances based on the cable parameters and fault impedance model of the power cable. The fault model integrates multiple types of power cable fault instances and can simulate various types of faults in different types of power cables. Therefore, in the actual simulation process, after specifying a specific fault type through the fault model, the user can conduct specific fault location training for that fault type.

[0066] It should be noted that the fault model constructed above needs to be optimized before it can be applied to simulation training. Therefore, after the fault location simulation is performed through the fault model, it is necessary to simulate the power cable fault instance based on the fault model, that is, specify several power cable fault types, and locate the power cable fault based on the power cable fault type, so as to obtain the corresponding location results and fault parameters. The fault parameters mainly include fault resistance, capacitance, fault signal propagation speed, etc. By comparing the fault parameters with the actual fault parameters corresponding to the cable fault instance, it can be determined whether the simulation results obtained by the fault model are consistent with the actual fault instance. If it is consistent, it means that the current fault model can simulate each fault type more accurately and provide more accurate fault information. If it is not consistent, it means that the current fault model needs to be optimized. Therefore, it is necessary to determine the fault parameters that are significantly different from the actual fault parameters based on the comparison results, and then determine the cable parameter types that can affect the accuracy of the fault parameters. They are the cable parameter types that need to be adjusted in the end. Cable parameter types include at least conductor parameters (such as material, cross-sectional area, shape, etc.), insulation parameters (such as material, thickness, dielectric constant, etc.), cable structure parameters (such as number of cores, twisting method, etc.), electrical performance parameters (such as resistance, capacitance, inductance values ​​and their changing frequency with frequency, temperature, humidity, etc.), and signal propagation speed.

[0067] After determining the type of cable parameters that need to be adjusted, the cable parameters contained in the cable parameter type can be adjusted. The following are several examples of cable parameter adjustment: (1) Conductor parameter adjustment: If the resistance is inconsistent with the resistance in the actual power cable fault example, the cross-sectional area of ​​the conductor needs to be adjusted according to the resistance formula (Where R is resistance, ρ is resistivity, L is length, and S is cross-sectional area), appropriately increase or decrease the cross-sectional area to change the resistance value. (2) Insulation parameter adjustment: If the capacitance value is different from the actual value, you can adjust the capacitance value according to the capacitance formula (where C is capacitance, ε is dielectric constant, S is plate area, and d is plate spacing), adjust the dielectric constant to correct the capacitance value. You can also change the inductance and capacitance by increasing the number of cores or changing the twisting method, according to the formula (where L is the inductance, μ is the magnetic permeability, N is the number of turns of the coil, S is the cross-sectional area of ​​the coil, and l is the length of the coil). By adjusting these parameters, the values ​​of inductance and capacitance can be changed, thereby adjusting the signal propagation speed and attenuation. (3) Fault resistance adjustment: Assume that the fault resistance is R f , and the cable resistance R c In series, the current in the circuit is I, and the power supply voltage is V, then: V = I × (R c +R f ), when adjusting the actual fault resistance, directly adjust R according to the size and variation range of the actual fault resistance. f The value of is modified to the corresponding value. (4) Signal propagation speed adjustment: According to the formula (where v is the signal propagation speed, L is the inductance, and C is the capacitance), and the propagation speed is changed by adjusting the inductance or capacitance. The adjusted cable parameters can be used to update the fault model. After obtaining the updated fault model, the power cable is re-simulated and positioned, and the re-simulated fault parameters are compared with the actual fault instance to determine whether there is a difference between them, until the difference between the fault parameters and the actual fault parameters meets the preset difference range, and the final optimized fault model is obtained.

[0068] S102: Determine the training stage that the user is in, and select a target power cable fault type that matches the training stage from a plurality of power cable fault types corresponding to the fault model.

[0069] Power cables are usually laid in urban cable tunnels, factory distribution rooms, substations and other locations. For power cables in different locations, the common fault types are different. Therefore, in order to provide users with more targeted simulated fault data, it is necessary to set up a variety of training scenarios when conducting simulation training for users. The detection skills and difficulty that users need to learn in each training scenario are different.

[0070] Since the user's training stage can be divided into multiple levels, the difficulty of the skills required for training in each training stage is also different. Therefore, it is necessary to select the power cable fault type related to the current training scenario as the candidate power cable fault type based on the various power cable fault types provided by the fault model, and then select the matching target power cable fault type as the user's training target according to the user's current training stage.

[0071] Specifically, the training stage is divided into the initial training stage, the platform training stage and the convergence training stage according to the different training progress. In different training stages, the degree of mastery of fault location by users varies. Generally speaking, the initial training stage refers to the user's new contact with power cable fault location training, the platform training stage refers to the user's ability to handle some common cable faults but is still not proficient in complex faults, and the convergence stage refers to the user's strong ability to handle rare and difficult-to-diagnose faults. The division of the training stage is determined based on the user's historical training data. If a user does not have historical training data, it can be directly determined that it is in the initial training stage. For users with historical training data, it is necessary to determine the power cable fault type that the user participates in training in each training process and its corresponding operation evaluation value based on the historical training data. The operation evaluation value is an indicator value obtained by comprehensive evaluation based on whether the user's operation position is accurate, whether the equipment used is correct, and whether the time for discharge and power testing is reasonable. It is used to evaluate the user's operation accuracy. Generally speaking, the higher the operation evaluation value, the better the user's mastery of this type of fault type.

[0072] After obtaining the operation evaluation value corresponding to each power cable fault type, a specified power cable fault type whose operation evaluation value is less than a preset value is selected. The preset value is used to determine whether the user can pass the minimum training requirements. When the operation evaluation value corresponding to the specified power cable fault type is less than the preset value, it means that the user cannot pass the passing standard required by the fault type. Therefore, for these specified power cable fault types that have not passed the training requirements, the training stage of the current user can be determined by analyzing their corresponding training results. The training results can be characterized by the growth amount of the operation evaluation value. Specifically, for the specified power cable fault type, the growth amount of the corresponding operation evaluation value of the specified power cable fault type in different training processes is determined. According to the growth amount of the operation evaluation value generated in each training process and the previous training process, the training stage of the user can be determined. Among them, the training stage includes at least three training stages, namely, the initial training stage with a growth amount greater than the first growth amount, the platform training stage with a growth amount less than the first growth amount and greater than the second growth amount, and the convergence training stage with a growth amount less than the second growth amount.

[0073] It should be noted that since there may be multiple designated power cable fault types, when judging the training stage based on the growth amount, the training stage corresponding to each designated power cable fault type may not be the same. However, when determining the user's training stage, it is evaluated based on the user's overall training progress. Therefore, when determining multiple different training stages, it is necessary to consider the impact of the slowest designated power cable fault type on the training stage judgment results.

[0074] Specifically, it is determined whether there is any specified power cable fault type whose corresponding growth amount is greater than the first growth amount. If so, it is determined that the training stage of the user is the initial training stage. If not, it is necessary to determine whether the growth amount corresponding to any specified power cable fault type is less than the first growth amount and greater than the second growth amount. If so, it is determined that the training stage of the user is the platform training stage, otherwise, it is determined that the training stage of the user is the convergence training stage. In other words, as long as there is a growth amount corresponding to a certain specified power cable fault type in a training stage with a slower progress, the slowest training stage will be directly selected as the training stage of the user. For example, the fault type of short circuit fault is in the initial training stage, and the fault type of low resistance fault is in the platform training stage. According to the above judgment principle, the training stage of the user is finally the initial training stage. When the training progress of users on different fault types is different, by paying attention to the training stage with the slowest training progress, it can be ensured that users learn the detection skills corresponding to different fault types more comprehensively, and ensure that users of various types of power cable faults can fully master them.

[0075] After determining the training stage the user is in, it is necessary to clarify the training objectives of the current training stage. Specifically, each training stage has its corresponding standard operation evaluation value. The standard operation evaluation value is a comprehensive evaluation value corresponding to the operation requirements expected to be achieved in a training stage, and the standard operation evaluation value is positively correlated with the growth amount. From the various power cable fault types corresponding to the fault model, the power cable fault types whose corresponding operation evaluation values ​​are lower than the standard operation evaluation values ​​are selected as the target power cable fault types that match the training stage. The target power cable fault types finally screened out indicate that the user's operation effects on them have not yet reached the expected level, so these target power cable fault types need to be used as the training focus of the current training stage. By screening the target power cable fault types in different training stages, resources can be concentrated to improve the processing capabilities of these types of faults in a targeted manner, thereby improving the overall training effect of the user.

[0076] S103: Loading a fault model and a preset electromagnetic interference model to generate a simulation training scenario for a target power cable fault type, and receiving an operation instruction sent by a user through an interactive device in the simulation training scenario.

[0077] After clarifying the content that the current user needs to be trained on, the virtual simulation system needs to build a simulated training scenario for simulating fault location. Based on the simulated training scenario, users can wear high-resolution, low-latency VR glasses and use ergonomically designed handles and other input devices to operate. During the entire simulation training process, the user's dress code, correct wearing of safety equipment, selection and use of tools and other preparatory work links need to be simulated accordingly, and for core operation processes such as discharge, electrical testing, instrument use, cable connector removal and installation, high-precision physical simulation and animation technology are required for fine simulation. According to the established fault model, the fault parameters corresponding to various target power cable fault types are simulated in real time and dynamically, and finally the corresponding simulation positioning results are fed back to the user's operation.

[0078] It should be noted that when simulating fault location of power cables, the impact of on-site environmental factors on simulation results must also be considered. Generally, there will be a certain amount of electromagnetic interference at the test site, resulting in errors in instrument readings. Therefore, in order to more accurately simulate the actual detection process and enable users to experience the complexity and diversity of the real working environment, the virtual simulation system needs to load the fault model and the preset electromagnetic interference model at the same time when building the simulation training scene, so as to add corresponding environmental interference to the simulation training scene and generate a simulation training scene for the target power cable fault type. In the simulation training scene, users can wear VR equipment and use input devices such as handles to simulate the detection of power cables. After the user takes corresponding operations through the input device, the computer host can receive the operation instructions sent by the user through the interactive device in the simulation training scene, such as discharge, power test, etc.

[0079] Among them, the electromagnetic interference model tests the impact on the simulated training environment by simulating electromagnetic interference sources of different frequencies, intensities and sources. The electromagnetic interference model can cause the waveform of the pulse signal displayed on the oscilloscope UI to be deformed, and the measurement of the peak and time parameters to deviate, thereby causing errors in the key parameters such as the arrival time and amplitude of the fault reflection wave read, thereby affecting the accuracy of fault location. The electromagnetic interference model can be expressed as:

[0080] E=E 0 +k 1 f(I,V,d,t)

[0081] H=H 0 +k 2 g(I,V,d,t)

[0082] Among them, E 0 and H 0 are the electric and magnetic field strengths, k 1 and k 2is a constant, f and g are functions constructed based on electromagnetic theory and actual measurement data, which are used to describe the influence of factors such as current I, voltage V, distance d and time t on the electric field and magnetic field strength.

[0083] S104: converting the operation instruction into operation parameters corresponding to the power cable to be located, locating the fault in the power cable according to the operation parameters and the power cable parameters corresponding to the power cable, so as to obtain corresponding fault information and realize fault simulation positioning of the power cable.

[0084] According to the operation instructions sent by the user, the computer host needs to convert them into operation parameters corresponding to the power cable to be located. The operation parameters need to include information such as specific operation tools, operation positions, and operation time. According to the operation parameters and the power cable parameters corresponding to the power cable, the faults existing in the power cable can be located, thereby obtaining the corresponding fault information and realizing the fault simulation location of the power cable.

[0085] In one embodiment, the computer host needs to determine whether the operating parameters match the target operating parameters corresponding to the target power cable fault type when locating the fault. If they match, it means that the current user operation is correct, and the corresponding fault information can be simulated and output and fed back to the user. At this time, it is necessary to collect the reflected wave corresponding to the pulse signal sent by the power cable in response to the operation instruction, and extract the fault characteristics in the reflected wave through wavelet transform; wherein the fault characteristics include at least one or more of the following: signal arrival time, reflected wave amplitude, reflected wave frequency. According to the fault characteristics, the distance between the fault point in the power cable and the measurement point corresponding to the operation instruction is calculated to obtain the fault information corresponding to the power cable.

[0086] Specifically, after obtaining the signal arrival time t, the signal propagation speed in the cable is known to be v. First, based on the signal propagation speed and signal arrival time, the total round trip distance of the signal in the cable can be calculated S = v × t. Since the arrival time of the reflected wave is measured, the signal actually travels a round trip in the cable, so the distance L from the fault point to the measurement end is calculated by the following formula:

[0087] However, in actual situations, the structural parameters of the cable also need to be considered. If the cable has branches or uneven parts, the propagation speed may need to be corrected according to the specific structure of the cable. Assuming that the cable is composed of parts of different materials or cross-sectional areas, the cable can be divided into n segments, each of which has a length of L i , it is known that the propagation speed of the signal in the cable is v i .

[0088] Then the total stroke S can be expressed as:

[0089] The distance L from the fault point to the measuring end is:

[0090] In addition, the amplitude reflects the severity of the fault and the energy of the reflected wave; the frequency characteristics help to determine the type and nature of the fault. For example, different fault types may cause the reflected wave to have different frequency components. Different fault types correspond to different frequency characteristics. The frequency components of the reflected wave corresponding to a point grounding fault may be relatively simple, mainly concentrated in the lower frequency band. Multi-point grounding faults may produce more complex frequency components distributed in multiple frequency bands. For faults caused by insulation aging, the frequency of the fault signal may be more obvious in the mid-frequency band. The frequency characteristic is the frequency of the fault signal. By analyzing the frequency characteristics, it can assist in determining the type and nature of the fault. For example, if the low-frequency components of the detected reflected wave are strong and concentrated, it may indicate a single-point grounding fault; if there is significant energy distribution in multiple frequency bands, it may be more inclined to a multi-point grounding fault.

[0091] In one embodiment, the initially extracted fault features are corrected by combining fault model data, cable parameters (such as cable length, material, cross-sectional area, etc.), and signal propagation speed information. For example, the propagation speed of the signal in the cable is accurately calculated based on the material and structure of the cable; the arrival time and amplitude of the reflected wave are corrected by considering the influence of the fault resistance on the signal reflection and attenuation; the attenuation degree of the signal is compensated according to the laying environment and length of the cable, etc.

[0092] For example, for a cable of a specific material (such as copper) and structure (such as single-core with insulation), its dielectric constant and magnetic permeability are known, and the propagation speed is calculated using electromagnetic formulas. Assuming that the measured arrival time of the reflected wave is t0, the estimated fault resistance is R f After determining the fault resistance information in the power cable according to the fault model, the delay time Δt caused by the fault resistance can be calculated according to the fault resistance information. Then, the signal arrival time can be corrected according to the delay time. The corrected arrival time is the sum of the delay time and the signal arrival time, expressed as t = t 0 +Δt. If the original reflected wave amplitude is A 0 , the attenuation coefficient due to the fault resistance is calculated to be α, then the corrected amplitude is A = A 0 / α. For a cable with a length of L laid in a specific environment, the attenuation coefficient in the environment is known to be β, and the measured reflected wave amplitude is B 0 , then the amplitude after compensation is B = B 0 ×β L .

[0093] The above are embodiments of the method proposed in this application. Based on the same idea, some embodiments of this application also provide devices and non-volatile computer storage media corresponding to the above methods.

[0094] Figure 2 A schematic diagram of the structure of a simulation device for locating power cable faults provided in an embodiment of the present application. Figure 2 As shown, including:

[0095] at least one processor; and,

[0096] at least one processor is communicatively connected to a memory; wherein,

[0097] The memory stores instructions executable by at least one processor, and the instructions are executed by at least one processor so that the at least one processor can execute a simulation method for power cable fault location as described in any one of the above items.

[0098] The embodiment of the present application provides a non-volatile computer storage medium storing computer executable instructions, wherein the computer executable instructions are configured as follows:

[0099] A simulation method for power cable fault location as described in any one of the above items.

[0100] Each embodiment in this application is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device and medium embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiments.

[0101] The devices and media provided in the embodiments of the present application correspond one-to-one to the methods. Therefore, the devices and media also have similar beneficial technical effects as the corresponding methods. Since the beneficial technical effects of the methods have been described in detail above, the beneficial technical effects of the devices and media will not be repeated here.

[0102] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0103] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0104] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0105] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0106] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0107] The memory may include non-permanent storage in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0108] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0109] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0110] The above is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A simulation method for locating power cable faults, characterized in that: Applied to a preset virtual simulation system, the method comprises: Collecting power cable fault instances, and establishing a fault model for simulating various power cable fault types according to the power cable fault instances; Determine the training stage of the user, and select a target power cable fault type that matches the training stage from a plurality of power cable fault types corresponding to the fault model; Loading the fault model and the preset electromagnetic interference model to generate a simulation training scenario for the target power cable fault type, and receiving an operation instruction sent by the user through an interactive device in the simulation training scenario; The operation instruction is converted into operation parameters corresponding to the power cable to be located, and the fault existing in the power cable is located according to the operation parameters and the power cable parameters corresponding to the power cable to obtain corresponding fault information, thereby realizing fault simulation positioning of the power cable.

2. A simulation method for power cable fault location according to claim 1, characterized in that: Determine the user's training stage, including: Acquire historical training data of the user, and determine the power cable fault type and its corresponding operation evaluation value that the user participated in training in each training process according to the historical training data; Selecting a specified power cable fault type whose operation evaluation value is less than a preset value, and determining, for the specified power cable fault type, an increase in the corresponding operation evaluation value of the specified power cable fault type during different training processes; According to the growth amount, determine the training stage of the user; wherein the training stage includes at least three training stages, namely, an initial training stage in which the growth amount is greater than a first growth amount, a platform training stage in which the growth amount is less than the first growth amount and greater than a second growth amount, and a convergence training stage in which the growth amount is less than the second growth amount.

3. A simulation method for power cable fault location according to claim 2, characterized in that: Selecting a target power cable fault type that matches the training stage from a plurality of power cable fault types corresponding to the fault model specifically includes: Obtaining a standard operation evaluation value corresponding to the training stage; wherein the standard operation evaluation value is positively correlated with the growth amount; From the multiple power cable fault types corresponding to the fault model, a power cable fault type corresponding to an operation evaluation value lower than the standard operation evaluation value is selected as a target power cable fault type matching the training stage.

4. A simulation method for power cable fault location according to claim 2, characterized in that: Determining the training stage of the user according to the growth amount specifically includes: Determine whether there is any specified power cable fault type whose corresponding growth amount is greater than the first growth amount, and if so, determine that the training stage of the user is the initial training stage; If not, when the growth amount corresponding to any specified power cable fault type is less than the first growth amount and greater than the second growth amount, it is determined that the training stage of the user is the platform training stage; otherwise, it is determined that the training stage of the user is the convergence training stage.

5. A simulation method for power cable fault location according to claim 1, characterized in that: According to the power cable fault example, a fault model for simulating various power cable fault types is established, specifically including: Extracting cable parameters corresponding to the power cable from the power cable fault instance; For the power cable to be located, abstract it into a corresponding uniform transmission line model, and determine the electrical transmission characteristics corresponding to the power cable based on the uniform transmission line model; According to the electrical transmission characteristics, a fault impedance model for simulating various power cable fault types is constructed; wherein the fault impedance model can be expressed as: Among them, Γ f is the reflection coefficient at the end of the cable. If the end of the cable is open (Z f =∞), then Γ f =1; Z f represents the impedance at the end of the cable, Z0 represents the characteristic impedance at the fault location, e -2γ(l-x) An exponential term representing the signal propagation related to the cable; According to the fault impedance model and cable parameters of different types of power cables, fault models corresponding to different power cable fault instances are constructed.

6. A simulation method for power cable fault location according to claim 1, characterized in that: After establishing a fault model for simulating multiple types of power cable faults according to the power cable fault example, the method further includes: Based on the fault model, a simulation training is performed on the power cable fault instance to obtain corresponding fault parameters; Comparing the fault parameters with actual fault parameters corresponding to the power cable fault instance, so as to determine the type of cable parameters to be adjusted according to the comparison result; wherein the cable parameter type includes at least conductor parameters, insulation parameters, cable structure parameters, electrical performance parameters, and signal propagation speed; The cable parameters included in the cable parameter type are adjusted, and the fault model is updated using the adjusted cable parameters until the difference between the fault parameter and the actual fault parameter satisfies a preset difference range.

7. A simulation method for power cable fault location according to claim 1, characterized in that: Locating a fault in the power cable according to the operating parameter and a power cable parameter corresponding to the power cable to obtain corresponding fault information specifically includes: Determining whether the operating parameter matches a target operating parameter corresponding to the target power cable fault type when performing fault location; If yes, collect the reflected wave corresponding to the pulse signal sent by the power cable in response to the operation instruction, and extract the fault characteristics in the reflected wave by wavelet transform; wherein the fault characteristics include at least one or more of the following: signal arrival time, reflected wave amplitude, reflected wave frequency; According to the fault feature, the distance between the fault point in the power cable and the measurement point corresponding to the operation instruction is calculated to obtain fault information corresponding to the power cable.

8. A simulation method for power cable fault location according to claim 7, characterized in that: After extracting the fault feature in the reflected wave, the method further includes: Determine, according to the fault model, information about a fault resistance in the power cable, and determine, according to the fault resistance information, a delay time caused by the fault resistance to the reflected wave; The signal arrival time is corrected according to the delay time, so that the sum of the delay time and the signal arrival time is used as the corrected signal arrival time.

9. A simulation device for locating power cable faults, characterized in that: Applied to a preset virtual simulation system, the device comprises: at least one processor; and, a memory communicatively coupled to the at least one processor; The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute a simulation method for power cable fault location as described in any one of claims 1-8.

10. A non-volatile computer storage medium storing computer executable instructions, characterized in that: Applied to a preset virtual simulation system, the computer executable instructions are set to: A simulation method for power cable fault location as described in any one of claims 1 to 8.

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