A power distribution network fault detection method, device, equipment and storage medium

Abstract

The application discloses a power distribution network fault detection method, device and equipment and a storage medium. The method comprises the following steps: collecting electrical information of a target area in a power distribution network, the target area having a fault point with a fault; under the condition that the fault point is assumed to be distributed on each branch of the target area, detecting a first position of the fault point in the target area according to the electrical information; detecting a second position of the fault point in the target area according to voltage traveling waves propagated by the fault point; checking the effectiveness of the first position according to the second position; and if the first position is checked to be effective, determining that the fault point is at the first position in the target area. The embodiment positions the fault point from multiple dimensions, checks the first position of the fault point positioned according to the assumption distribution according to the second position of the fault point positioned according to the voltage traveling waves, and thus the accuracy of fault point positioning can be improved.

Description

Technical Field

[0001] This invention relates to the technical field of power grids, and more particularly to a fault detection method, apparatus, equipment, and storage medium for distribution networks. Background Technology

[0002] With the continuous improvement of residents' living standards and the rapid development of the economy, the development of urban power has become increasingly rapid. The use of a large number of household appliances has led to a significant increase in residents' electricity consumption, constantly creating new peak electricity consumption levels.

[0003] The power distribution network is a crucial link in ensuring a stable and reliable power supply for residents. It is directly installed in cities, and the complex operating environment and increasingly complex network structure have reduced its stable operation capabilities. Various types of faults frequently occur in the power system distribution network, which has a significant impact on the stable and reliable power supply for residents.

[0004] Ensuring the use of a large number of residential electrical appliances and meeting residents' needs for power quality is a crucial aspect that directly affects residential electricity consumption. Currently, fault location in the distribution network is mainly achieved through methods such as waveform shape comparison and entropy method. However, these methods are limited and result in low accuracy in fault location. Summary of the Invention

[0005] This invention provides a method, apparatus, equipment, and storage medium for fault detection in power distribution networks, in order to solve the problem of how to improve the accuracy of fault location in power distribution networks.

[0006] According to one aspect of the present invention, a fault detection method for a power distribution network is provided, comprising:

[0007] Electrical information is collected from a target area in the power distribution network, where the target area contains fault points where faults have occurred;

[0008] Assuming the fault point is distributed on each branch of the target area, the first location of the fault point in the target area is detected based on the electrical information.

[0009] The second location of the fault point in the target area is detected based on the voltage traveling wave propagating from the fault point in the target area;

[0010] The validity of the first position is verified based on the second position;

[0011] If the first location is verified to be valid, then the fault point is determined to be located at the first location in the target area.

[0012] Optionally, the step of detecting the first location of the fault point in the target area based on the electrical information, assuming that the fault point is distributed on various branches of the target area, includes:

[0013] Query the branch types in the target area;

[0014] If the branch type is a single branch area, then the fault point is determined to be located on a single feeder within the target area, and the first position of the fault point on the single feeder is detected based on the electrical information.

[0015] If the branch type is a multi-branch area, then it is assumed that the fault point is distributed on each feeder of the target area in sequence, and the first position of the fault point on a certain feeder is detected based on the electrical information on the port of each target area.

[0016] Optionally, the step of sequentially assuming that the fault points are distributed on each feeder in the target area, and detecting the first location of the fault point on a certain feeder based on the electrical information on the port in the target area, includes:

[0017] The fault point is set as the target line in the target area, and the target line is initially the first feeder in the target area;

[0018] The electrical information on the ports in the target area is used to form a set of multi-terminal fault location equations;

[0019] Solve the multi-terminal fault location equations to obtain the fault measurement value of the fault point being located on the target line.

[0020] Determine whether the fault measurement value is within a preset fault range;

[0021] If so, the first position of the fault point on the target line is calculated based on the fault measurement value;

[0022] If not, then set the next feeder located on the current target line as the new target line, and return to the execution of the target line where the fault point is set in the target area.

[0023] Optionally, the electrical information includes the phase angle of the voltage and the phase angle of the current at the fault point;

[0024] The electrical information on the ports in the target area is used to form a multi-terminal fault location equation set, including:

[0025] Query the length of the target line;

[0026] Substitute the fault measurement value, the phase angle of the voltage, the phase angle of the current, and the length of the target line into a preset mapping function;

[0027] The value output by the mapping function is set to 0, which serves as the multi-terminal fault location equation set.

[0028] Optionally, detecting the second location of the fault point in the target area based on the voltage traveling wave propagating from the fault point in the target area includes:

[0029] Determine the route in which the fault point is located within the target area;

[0030] When a fault occurs at the fault point, the voltage traveling wave propagating from the fault point to both ends of the line is collected;

[0031] A set of propagation equations is constructed based on the times at which the voltage traveling wave is received at both ends of the line;

[0032] Solving the propagation equations yields the second location of the fault point on the line.

[0033] Optionally, the propagation equations include:

[0034]

[0035]

[0036] Where M and N are the two ends of the line, L is the length of the line, and t is the length of the line. M t is the time when the voltage traveling wave is received at terminal M. N The time when the voltage traveling wave is received at the N terminal is v, the frequency of the traveling wave is v, l1 is the distance between the fault point and the M terminal, and l2 is the distance between the fault point and the N terminal. l1 and l2 together represent the second position of the fault point on the line.

[0037] Optionally, the step of validating the first position based on the second position includes:

[0038] Calculate the error between the first position and the second position;

[0039] If the error is less than a preset threshold, then the validity of the first position is determined to be valid.

[0040] According to another aspect of the present invention, a fault detection device for a power distribution network is provided, comprising:

[0041] An electrical information acquisition module is used to acquire electrical information from a target area in a power distribution network, wherein the target area contains fault points where faults have occurred.

[0042] A multi-point monitoring module is used to detect the first location of the fault point in the target area based on the electrical information, assuming that the fault point is distributed on each branch of the target area.

[0043] A traveling wave ranging module is used to detect the second location of the fault point in the target area based on the voltage traveling wave propagating from the fault point in the target area;

[0044] A location verification module is used to verify the validity of the first location based on the second location;

[0045] The fault determination module is used to determine that the fault point is located at the first position in the target area if the first position is verified to be valid.

[0046] Optionally, the multi-point monitoring module includes:

[0047] The branch type query module is used to query the branch types in the target area;

[0048] A single-branch processing module is used to determine that if the branch type is a single-branch area, the fault point is located on a single feeder within the target area, and to detect the first position of the fault point on the single feeder based on the electrical information.

[0049] A multi-branch processing module is used to, if the branch type is a multi-branch area, sequentially assume that the fault point is distributed on each feeder of the target area, and detect the first position of the fault point on a certain feeder based on the electrical information on the port of each target area.

[0050] Optionally, the multi-branch processing module includes:

[0051] The target line setting module is used to set the fault point as a target line in the target area, wherein the target line is initially the first feeder in the target area;

[0052] A ranging equation set construction module is used to compose a multi-terminal fault ranging equation set using the electrical information on the ports of the target area;

[0053] The ranging equation solving module is used to solve the multi-terminal fault ranging equation system to obtain the fault measurement value of the fault point being located on the target line.

[0054] The fault measurement value judgment module is used to determine whether the fault measurement value is within a preset fault range; if yes, the position calculation module is called; if no, the target line update module is called.

[0055] The location calculation module is used to calculate the first position of the fault point on the target line based on the fault measurement value;

[0056] The target line update module is used to set the next feeder located on the current target line as the new target line, and then return to execute the target line setting module, the ranging equation set construction module, the ranging equation set solving module, and the fault measurement value judgment module.

[0057] Optionally, the electrical information includes the phase angle of the voltage and the phase angle of the current at the fault point;

[0058] The distance measurement equation system construction module is also used for:

[0059] Query the length of the target line;

[0060] Substitute the fault measurement value, the phase angle of the voltage, the phase angle of the current, and the length of the target line into a preset mapping function;

[0061] The value output by the mapping function is set to 0, which serves as the multi-terminal fault location equation set.

[0062] Optionally, the traveling wave ranging module includes:

[0063] The route determination module is used to determine the route where the fault point is located in the target area;

[0064] A voltage traveling wave acquisition module is used to acquire the voltage traveling wave that propagates from the fault point to both ends of the line when a fault occurs at the fault point.

[0065] A propagation equations construction module is used to construct a propagation equations system based on the times when the voltage traveling wave is received at both ends of the line.

[0066] The propagation equations solving module is used to solve the propagation equations to obtain the second location of the fault point on the line.

[0067] Optionally, the propagation equations include:

[0068]

[0069]

[0070] Where M and N are the two ends of the line, L is the length of the line, and t is the length of the line. M t is the time when the voltage traveling wave is received at terminal M. NThe time when the voltage traveling wave is received at the N terminal is v, the frequency of the traveling wave is v, l1 is the distance between the fault point and the M terminal, and l2 is the distance between the fault point and the N terminal. l1 and l2 together represent the second position of the fault point on the line.

[0071] Optionally, the location verification module includes:

[0072] The error calculation module is used to calculate the error between the first position and the second position;

[0073] The effective determination module is used to determine the effectiveness of the first position as effective if the error is less than a preset threshold.

[0074] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising:

[0075] At least one processor; and

[0076] A memory communicatively connected to the at least one processor; wherein,

[0077] The memory stores a computer program that can be executed by the at least one processor, which enables the at least one processor to perform the fault detection method for the power distribution network according to any embodiment of the present invention.

[0078] According to another aspect of the present invention, a computer-readable storage medium is provided, the computer-readable storage medium storing a computer program, the computer program being configured to cause a processor to execute and implement the fault detection method for a power distribution network according to any embodiment of the present invention.

[0079] In this embodiment, electrical information is collected from a target area in the distribution network, and the target area contains fault points where faults have occurred. Assuming the fault points are distributed across various branches within the target area, a first location of the fault point in the target area is detected based on the electrical information. A second location of the fault point in the target area is detected based on the voltage traveling wave propagating from the fault point. The validity of the first location is verified based on the second location. If the first location is verified as valid, the fault point is determined to be in the first location within the target area. This embodiment locates the fault point from multiple dimensions. Verifying the first location of the fault point based on the second location using the voltage traveling wave improves the accuracy of fault point location. Furthermore, both methods have broad applicability, satisfying various business scenarios for fault point location.

[0080] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0081] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0082] Figure 1 This is a flowchart of a fault detection method for a power distribution network according to Embodiment 1 of the present invention;

[0083] Figure 2 This is a schematic diagram of a branch model provided in Embodiment 1 of the present invention;

[0084] Figure 3 This is a schematic diagram of voltage traveling wave transmission according to Embodiment 1 of the present invention;

[0085] Figure 4 This is a schematic diagram of the structure of a fault detection device for a power distribution network according to Embodiment 2 of the present invention;

[0086] Figure 5 This is a schematic diagram of the structure of an electronic device provided in Embodiment 3 of the present invention. Detailed Implementation

[0087] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0088] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0089] Example 1

[0090] Figure 1 This is a flowchart of a fault detection method for a distribution network provided in Embodiment 1 of the present invention. This embodiment is applicable to situations where the results of using voltage traveling wave to locate distribution network faults are used to verify the results of using multi-point monitoring to locate distribution network faults. This method can be executed by a fault detection device for the distribution network, which can be implemented in hardware and / or software and can be configured in electronic equipment. Figure 1 As shown, the method includes:

[0091] Step 101: Collect electrical information for the target area in the power distribution network.

[0092] Multiple PUMs (phasor measurement units) are installed at power outlets and other locations in the power distribution network. The PUMs can continuously collect electrical information in the power distribution network and upload it to the monitoring master station. The monitoring master station then uploads the electrical information to a cloud server for analysis.

[0093] Among them, PUM is a phasor measurement unit that uses the second pulse of the satellite positioning system as a synchronization clock. It can be used in the fields of dynamic monitoring, system protection, system analysis and prediction of power systems.

[0094] Clock-based PMUs can measure phasor data such as voltage phase and current phase at key points in the power system. The data is transmitted to the monitoring master station via the communication network. Based on the phase amplitude at different points, the monitoring master station determines how the system should disconnect, switch off generators, and disconnect loads when subjected to system disturbances, in order to prevent the further escalation of the accident or even grid collapse.

[0095] According to functional requirements, the PMU includes a synchronous sampling trigger pulse generation module, a synchronous phasor measurement and calculation module, and a communication module.

[0096] The main function of the synchronous sampling trigger pulse generation module is to provide a second pulse and the current standard time (accurate to the second). In order to reduce dependence on the satellite positioning system, a fairly accurate second pulse is provided by the machine's own crystal oscillator for a period of time after the satellite positioning system loses satellites.

[0097] The synchronous measurement and calculation module receives an analog AC signal as input. Its A / D (analog-to-digital converter) is triggered by an externally generated synchronous sampling pulse. After the digital-to-analog conversion is completed, it sends an interrupt signal to the signal processing module (Digital Signal Processing, DSP). The DSP performs a Digital Fourier Transform (DFF) operation on each data point it reads, comparing it with the previous sampled data to calculate the amplitude and phase of the fundamental wave of the AC signal. After calculating the phase, the DSP adds a corresponding time stamp and sends the phasor data from the communication interface to the monitoring master station or stores it on the local co-control unit.

[0098] In addition to the time stamp of the sampling point, synchronous serial communication data also includes the frequency of the current AC signal emitted by the CPU (Central Processing Unit).

[0099] If a fault occurs in a certain area of ​​the distribution network, it can be marked as a target area. That is, the target area contains the fault point. The electrical information collected in the target area is filtered from all electrical information, such as voltage, current, fault voltage, fault current, transition resistance, line length, etc., waiting to locate the fault point.

[0100] Step 102: Assuming the fault points are distributed on various branches of the target area, detect the first location of the fault points in the target area based on electrical information.

[0101] In this embodiment, based on the electrical information of the target area, a multi-point monitoring method can be used to locate the fault point in the target area and obtain the first location.

[0102] Generally, the first position can be represented by the distance of the fault point from the PUM.

[0103] Among them, the multi-point monitoring method can be assumed to be distributed in each feeder (also known as branch, line, etc.) in the target area. Under this condition, the possibility of the fault point being on a certain feeder in the target area is detected based on electrical information. The feeder with the highest probability is jointly analyzed, thereby locating the first position of the fault point on that feeder.

[0104] In one embodiment of the present invention, step 102 may include the following steps:

[0105] Step 1021: Query the branch types in the target area.

[0106] In this embodiment, to facilitate the location of fault points in the target area, a single feeder in the target area can be modeled to obtain a branch model representing the single feeder.

[0107] like Figure 2 As shown, the power source G on the left represents traditional power sources, especially fossil fuel power sources, such as coal power and natural gas power, while the power source DG on the left represents distributed power sources, especially new energy power sources, such as photovoltaic power and wind power.

[0108] PMUs are installed at all power outlets. Assume there is a fault point f on the line where a fault occurs, and the resistance of fault point f is R. f The current flowing through the fault point f is I. f Therefore, the impedance from sampling point 1 to fault point f is λZ, the impedance from sampling point 2 to fault point f is (1-λ)Z, and the voltage flowing through sampling point 1 is U. 1f The current is I 1f The voltage flowing through sampling point 2 is U 2f The current is I 2f .

[0109] Based on the branch model, the target area can be divided into different branch types, including single-branch model and multi-branch model. The single-branch model is a target area containing one feeder that conforms to the branch model, while the multi-branch model is a target area containing at least two feeders that conform to the branch model.

[0110] Step 1022: If the branch type is a single branch area, then determine that the fault point is located on a single feeder within the target area. Construct a double-ended fault network based on electrical information such as voltage and current, and then solve the double-ended fault network to detect the first position of the fault point on the single feeder.

[0111] If the target area is a single-branch area, that is, the target area has a single feeder, then the fault point can be determined to be located on the single feeder in the target area. Based on the electrical information detection, the voltage equation of the measurement point is constructed. The real and imaginary parts of the voltage equation of the measurement point are separated to obtain the ranging equation system. The ranging equation system is solved using methods such as the Newton-Raphson method to obtain the first position of the fault point on the single feeder.

[0112] Step 1023: If the branch type is a multi-branch area, then assume that the fault point is distributed on each feeder of the target area in turn, and detect the first position of the fault point on a certain feeder based on the electrical information on the port of each target area.

[0113] If the target area is a single-branch area, that is, the target area has a single feeder, then the fault point can be set to be distributed on each feeder of the target area in sequence. Under this condition, the first position of the fault point on a certain feeder can be detected based on the electrical information on the port of each target area.

[0114] In one embodiment of the present invention, step 1023 may further include the following steps:

[0115] Step 10231: Set the fault point on the target line in the target area.

[0116] In this embodiment, the first position of the fault point on a certain feeder is detected by multiple iterations. In each iteration, each feeder can be set as the target line in the target area in order of number, etc. The target line is initially the first feeder in the target area ordered in this order.

[0117] Step 10232: Use the electrical information on the ports of the target area to form a set of multi-terminal fault location equations.

[0118] Based on the established fault point, electrical information from each port in the target area can be used to form a set of voltage / impedance equations according to the electrical relationships of current, voltage, and impedance during a fault. By simplifying the voltage / impedance equations, a multi-terminal fault location equation set can be obtained.

[0119] For example, the electrical information includes the phase angle of the voltage and the phase angle of the current at the fault point. Then, the length of the target line is queried, and the fault measurement value, the phase angle of the voltage, the phase angle of the current and the length of the target line are substituted into a preset mapping function. The value output by the mapping function is set to 0, which serves as a set of multi-terminal fault location equations.

[0120] In this example, the multi-terminal fault location equations are expressed as follows:

[0121]

[0122] Where f is the first location of the fault point, λ is the fault measurement value, L is the length of the target line, α is the phase angle of the voltage, and β is the phase angle of the current.

[0123] Step 10233: Solve the multi-terminal fault location equation set to obtain the fault measurement value where the fault point is located on the target line.

[0124] In practical implementation, methods such as the Newton-Raphson method can be used to solve the multi-terminal fault location equations to obtain the fault measurement value where the fault point is located on the target line.

[0125] Step 10234: Determine whether the fault measurement value is within the preset fault range; if yes, proceed to step 10235; if no, proceed to step 10236.

[0126] Step 10235: Calculate the first position of the fault point on the target line based on the fault measurement value.

[0127] Step 10236: Set the next feeder located on the current target line as the new target line, and return to execute steps 10231-10234.

[0128] In this embodiment, it can be determined whether the fault measurement value is within a preset fault range (e.g., (0, 1)). If the fault measurement value is within the preset fault range, the probability that the fault point is located on the target line in the current iteration is high. At this time, the first position of the fault point on the target line can be finally confirmed based on the fault measurement value.

[0129] If the fault metric value is outside the preset fault range, the probability that the fault point is located on the target line in the current iteration is low. At this time, the next feeder line ordered on the current target line can be set as the new target line according to the number and other order, and the next iteration can be entered until the first position of the fault point on a certain feeder line is calculated.

[0130] Step 103: Detect the second location of the fault point in the target area based on the voltage traveling wave propagating from the fault point in the target area.

[0131] In practical applications, the primary voltage exhibits a distinct traveling wave characteristic, with voltage singularities appearing upon the arrival of the initial and reflected traveling waves. Due to the resonance of the inductance and capacitance within the CVT (capacitive voltage transformer), the CVT's frequency response has multiple resonant points, resulting in poor high-frequency response, especially with resonant damped CVTs. The energy stored within the CVT prevents the secondary voltage from rapidly following changes in the primary voltage.

[0132] Although the energy storage of a fast-saturating reactive damping CVT is much less than that of a resonant damping CVT, its high-frequency response and high-frequency signal tracking capability are still unsatisfactory due to the stray capacitance inside the CVT. When the traveling wave front of the primary voltage passes through the CVT, it causes low-frequency and high-frequency oscillations of the CVT. The traveling wave front is smoothed and stretched, and corresponding to the arrival of the initial traveling wave, the secondary voltage exhibits obvious high-frequency oscillations at the fault point.

[0133] The amplitude of the subsequent traveling wave is greatly reduced due to the attenuation of the line and the reflection at the fault point and the bus, but it can still be reflected in the secondary voltage of the CVT.

[0134] It is evident that although the traveling wave characteristics of the CVT secondary voltage are not as pronounced as those of the primary voltage, the arrival of the primary traveling wave can still be reflected in the secondary voltage. In other words, while the CVT secondary voltage cannot accurately transmit the primary traveling wave, it contains information about its arrival, with the initial traveling wave being the most obvious, and subsequent reflection and refraction wave detection also being relatively clear. Therefore, fault traveling wave location can still be achieved directly using the CVT secondary voltage.

[0135] Therefore, in this embodiment, sensors such as CVT can be used to detect the voltage traveling wave propagating in the target area, and the second location of the fault point in the target area can be detected based on the voltage traveling wave propagating in the target area.

[0136] In the specific implementation, the fault point is located on the line in the target area. Synchronization timing devices are installed at both ends of the line. The synchronization timing device can be an independent sensor or a module in a component such as a satellite positioning system. This embodiment does not limit this.

[0137] Using sensors such as CVTs to collect the voltage traveling wave propagating from the fault point to both ends of the line when a fault occurs, the traveling wave ranging method is implemented. Based on the time when the voltage traveling wave is received at both ends of the line, a propagation equation system is constructed. By solving the propagation equation system, the second location of the fault point on the line can be obtained.

[0138] Furthermore, such as Figure 3 As shown, suppose a fault occurs at point F on the line at time t, generating a voltage traveling wave. M and N are the two ends of the line, L is the length of the line, l1 is the distance between the fault point and end M, and l2 is the distance between the fault point and end N. M t is the time when the voltage traveling wave is received at terminal M. N This is the moment when the traveling voltage wave is received at terminal N.

[0139] Therefore, the propagation equations include:

[0140] l1=v(t M -t)]

[0141] l2=v(t N -t)]

[0142] Eliminating the time t when the fault occurs, and substituting l1 + l2 = L into the propagation equations, the propagation equations simplify to:

[0143]

[0144]

[0145] Where v is the frequency of the traveling wave, and l1 and l2 together characterize the second location of the fault point on the line.

[0146] Step 104: Verify the validity of the first position based on the second position.

[0147] In this embodiment, the first position calculated by the multi-point monitoring method is the primary position, and the second position calculated by the traveling wave ranging method is the secondary position. The validity of the first position is verified based on the second position, that is, whether the first position is valid.

[0148] In a practical implementation, the difference between the first position and the second position can be calculated as an error, and this error can be compared with a preset threshold.

[0149] If the error is less than the preset threshold, it means that the difference between the first position and the second position is small, and the validity of the first position can be determined as valid.

[0150] Step 105: If the first position is verified to be valid, then the fault point is determined to be in the first position in the target area.

[0151] If the validity of the first position is verified, the first position can be taken as the final result of fault detection, and the fault point can be determined to be in the first position in the target area.

[0152] In this embodiment, electrical information is collected from a target area in the distribution network, and the target area contains fault points where faults have occurred. Assuming the fault points are distributed across various branches within the target area, a first location of the fault point in the target area is detected based on the electrical information. A second location of the fault point in the target area is detected based on the voltage traveling wave propagating from the fault point. The validity of the first location is verified based on the second location. If the first location is verified as valid, the fault point is determined to be in the first location within the target area. This embodiment locates the fault point from multiple dimensions. Verifying the first location of the fault point based on the second location using the voltage traveling wave improves the accuracy of fault point location. Furthermore, both methods have broad applicability, satisfying various business scenarios for fault point location.

[0153] Example 2

[0154] Figure 4 This is a schematic diagram of the structure of a fault detection device for a power distribution network provided in Embodiment 2 of the present invention. Figure 4 As shown, the device includes:

[0155] Electrical information acquisition module 401 is used to acquire electrical information in a target area of ​​a power distribution network, wherein the target area contains fault points where faults have occurred;

[0156] The multi-point monitoring module 402 is used to detect the first location of the fault point in the target area based on the electrical information, assuming that the fault point is distributed on each branch of the target area.

[0157] The traveling wave ranging module 403 is used to detect the second position of the fault point in the target area based on the voltage traveling wave propagating from the fault point in the target area.

[0158] The position verification module 404 is used to verify the validity of the first position based on the second position;

[0159] The fault determination module 405 is used to determine that the fault point is located at the first position in the target area if the first position is verified to be valid.

[0160] In one embodiment of the present invention, the multi-point monitoring module 402 includes:

[0161] The branch type query module is used to query the branch types in the target area;

[0162] A single-branch processing module is used to determine that if the branch type is a single-branch area, the fault point is located on a single feeder within the target area, and to detect the first position of the fault point on the single feeder based on the electrical information.

[0163] A multi-branch processing module is used to, if the branch type is a multi-branch area, sequentially assume that the fault point is distributed on each feeder of the target area, and detect the first position of the fault point on a certain feeder based on the electrical information on the port of each target area.

[0164] In one embodiment of the present invention, the multi-branch processing module includes:

[0165] The target line setting module is used to set the fault point as a target line in the target area, wherein the target line is initially the first feeder in the target area;

[0166] A ranging equation set construction module is used to compose a multi-terminal fault ranging equation set using the electrical information on the ports of the target area;

[0167] The ranging equation solving module is used to solve the multi-terminal fault ranging equation system to obtain the fault measurement value of the fault point being located on the target line.

[0168] The fault measurement value judgment module is used to determine whether the fault measurement value is within a preset fault range; if yes, the position calculation module is called; if no, the target line update module is called.

[0169] The location calculation module is used to calculate the first position of the fault point on the target line based on the fault measurement value;

[0170] The target line update module is used to set the next feeder located on the current target line as the new target line, and then return to execute the target line setting module, the ranging equation set construction module, the ranging equation set solving module, and the fault measurement value judgment module.

[0171] In one embodiment of the present invention, the electrical information includes the phase angle of the voltage and the phase angle of the current at the fault point;

[0172] The distance measurement equation system construction module is also used for:

[0173] Query the length of the target line;

[0174] Substitute the fault measurement value, the phase angle of the voltage, the phase angle of the current, and the length of the target line into a preset mapping function;

[0175] The value output by the mapping function is set to 0, which serves as the multi-terminal fault location equation set.

[0176] In one embodiment of the present invention, the traveling wave ranging module 403 includes:

[0177] The route determination module is used to determine the route where the fault point is located in the target area;

[0178] A voltage traveling wave acquisition module is used to acquire the voltage traveling wave that propagates from the fault point to both ends of the line when a fault occurs at the fault point.

[0179] A propagation equations construction module is used to construct a propagation equations system based on the times when the voltage traveling wave is received at both ends of the line.

[0180] The propagation equations solving module is used to solve the propagation equations to obtain the second location of the fault point on the line.

[0181] In one embodiment of the present invention, the propagation equations include:

[0182]

[0183]

[0184] Where M and N are the two ends of the line, L is the length of the line, and t is the length of the line. M t is the time when the voltage traveling wave is received at terminal M. NThe time when the voltage traveling wave is received at the N terminal is v, the frequency of the traveling wave is v, l1 is the distance between the fault point and the M terminal, and l2 is the distance between the fault point and the N terminal. l1 and l2 together represent the second position of the fault point on the line.

[0185] In one embodiment of the present invention, the position verification module 404 includes:

[0186] The error calculation module is used to calculate the error between the first position and the second position;

[0187] The effective determination module is used to determine the effectiveness of the first position as effective if the error is less than a preset threshold.

[0188] The fault detection device for power distribution networks provided in this embodiment of the invention can execute the fault detection method for power distribution networks provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects for executing the fault detection method for power distribution networks.

[0189] Example 3

[0190] Figure 5 A schematic diagram of an electronic device 10 that can be used to implement embodiments of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices (e.g., helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0191] like Figure 5 As shown, the electronic device 10 includes at least one processor 11 and a memory, such as a read-only memory (ROM) 12 or a random access memory (RAM) 13, communicatively connected to the at least one processor 11. The memory stores computer programs executable by the at least one processor. The processor 11 can perform various appropriate actions and processes based on the computer program stored in the ROM 12 or loaded from storage unit 18 into the RAM 13. The RAM 13 may also store various programs and data required for the operation of the electronic device 10. The processor 11, ROM 12, and RAM 13 are interconnected via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0192] Multiple components in electronic device 10 are connected to I / O interface 15, including: input unit 16, such as keyboard, mouse, etc.; output unit 17, such as various types of displays, speakers, etc.; storage unit 18, such as disk, optical disk, etc.; and communication unit 19, such as network card, modem, wireless transceiver, etc. Communication unit 19 allows electronic device 10 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0193] Processor 11 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. Processor 11 performs the various methods and processes described above, such as fault detection methods for power distribution networks.

[0194] In some embodiments, the fault detection method for the distribution network can be implemented as a computer program tangibly contained in a computer-readable storage medium, such as storage unit 18. In some embodiments, part or all of the computer program can be loaded and / or installed on electronic device 10 via ROM 12 and / or communication unit 19. When the computer program is loaded into RAM 13 and executed by processor 11, one or more steps of the fault detection method for the distribution network described above can be performed. Alternatively, in other embodiments, processor 11 can be configured to perform the fault detection method for the distribution network by any other suitable means (e.g., by means of firmware).

[0195] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0196] Computer programs used to implement the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the processor, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be performed. The computer programs may be executed entirely on a machine, partially on a machine, or as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0197] In the context of this invention, a computer-readable storage medium can be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0198] To provide interaction with a user, the systems and techniques described herein can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the electronic device. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0199] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or computing systems that include middleware components (e.g., application servers), or computing systems that include frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

[0200] A computing system can include clients and servers. Clients and servers are generally located far apart and typically interact through communication networks. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or cloud host, which is a hosting product within the cloud computing service system to address the shortcomings of traditional physical hosts and VPS services, such as high management difficulty and weak business scalability.

[0201] Example 4

[0202] This invention also provides a computer program product, which includes a computer program that, when executed by a processor, implements the power distribution network fault detection method provided in any embodiment of this invention.

[0203] In implementing the computer program product, computer program code for performing the operations of this invention can be written in one or more programming languages ​​or a combination thereof. Programming languages ​​include object-oriented programming languages ​​such as Java, Smalltalk, and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0204] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0205] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A fault detection method for a power distribution network, characterized in that, include: Electrical information is collected from a target area in the power distribution network, where the target area contains fault points where faults have occurred; Assuming the fault point is distributed on various branches of the target area, the first location of the fault point in the target area is detected based on the electrical information; wherein, the first location is represented by the distance of the fault point from the detection device; The second location of the fault point in the target area is detected based on the voltage traveling wave propagating from the fault point in the target area; The validity of the first position is verified based on the second position; If the first location is verified to be valid, then the fault point is determined to be located at the first location in the target area.

2. The method according to claim 1, characterized in that, The step of detecting the first location of the fault point in the target area based on the electrical information, assuming that the fault point is distributed on various branches of the target area, includes: Query the branch types in the target area; If the branch type is a single branch area, then the fault point is determined to be located on a single feeder within the target area, and the first position of the fault point on the single feeder is detected based on the electrical information. If the branch type is a multi-branch area, then it is assumed that the fault point is distributed on each feeder of the target area in sequence, and the first position of the fault point on a certain feeder is detected based on the electrical information on the port of each target area.

3. The method according to claim 2, characterized in that, The step of assuming the fault points are distributed on each feeder in the target area, and detecting the first position of the fault point on a certain feeder based on the electrical information on the port in the target area, includes: The fault point is set as the target line in the target area, and the target line is initially the first feeder in the target area; The electrical information on the ports in the target area is used to form a set of multi-terminal fault location equations; Solve the multi-terminal fault location equations to obtain the fault measurement value of the fault point being located on the target line. Determine whether the fault measurement value is within a preset fault range; If so, the first position of the fault point on the target line is calculated based on the fault measurement value; If not, then set the next feeder located on the current target line as the new target line, and return to the execution of the target line where the fault point is set in the target area.

4. The method according to claim 3, characterized in that, The electrical information includes the phase angle of the voltage and the phase angle of the current at the fault point; The electrical information on the ports in the target area is used to form a multi-terminal fault location equation set, including: Query the length of the target line; Substitute the fault measurement value, the phase angle of the voltage, the phase angle of the current, and the length of the target line into a preset mapping function; The value output by the mapping function is set to 0, which serves as the multi-terminal fault location equation set.

5. The method according to claim 1, characterized in that, The method of detecting the second location of the fault point in the target area based on the voltage traveling wave propagating from the fault point in the target area includes: Determine the route in which the fault point is located within the target area; When a fault occurs at the fault point, the voltage traveling wave propagating from the fault point to both ends of the line is collected; A set of propagation equations is constructed based on the times at which the voltage traveling wave is received at both ends of the line; Solving the propagation equations yields the second location of the fault point on the line.

6. The method according to claim 5, characterized in that, The propagation equations include: Where M and N are the two ends of the line, L is the length of the line, and t is the length of the line. M t is the time when the voltage traveling wave is received at terminal M. N The time when the voltage traveling wave is received at the N terminal is v, the frequency of the traveling wave is v, l1 is the distance between the fault point and the M terminal, and l2 is the distance between the fault point and the N terminal. l1 and l2 together represent the second position of the fault point on the line.

7. The method according to any one of claims 1-6, characterized in that, The step of validating the first position based on the second position includes: Calculate the error between the first position and the second position; If the error is less than a preset threshold, then the validity of the first position is determined to be valid.

8. A fault detection device for a power distribution network, characterized in that, include: An electrical information acquisition module is used to acquire electrical information from a target area in a power distribution network, wherein the target area contains fault points where faults have occurred. A multi-point monitoring module is used to detect the first location of the fault point in the target area based on the electrical information, assuming that the fault point is distributed on various branches of the target area; wherein the first location is represented by the distance of the fault point from the detection device; A traveling wave ranging module is used to detect the second location of the fault point in the target area based on the voltage traveling wave propagating from the fault point in the target area; A location verification module is used to verify the validity of the first location based on the second location; The fault determination module is used to determine that the fault point is located at the first position in the target area if the first position is verified to be valid.

9. An electronic device, characterized in that, The electronic device includes: At least one processor; and A memory communicatively connected to the at least one processor; wherein, The memory stores a computer program that can be executed by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the fault detection method for the power distribution network according to any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the fault detection method for the power distribution network as described in any one of claims 1-7.

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