Transient filtering device and system suitable for dual-power-supply power distribution network

Abstract

The invention discloses a transient filtering device and system suitable for a dual-power-supply power distribution network. The transient filtering device suitable for the dual-power-supply power distribution network comprises a data acquisition unit, a data analysis unit, a data transmission unit and a power supply unit, the data acquisition unit is used for acquiring an electrical quantity signal of a distribution line and converting the electrical quantity signal into a digital signal; the data analysis unit is connected with the data acquisition unit and is used for analyzing impedance in the distribution line according to the digital signal and determining a fault distance; the data transmission unit is connected with the data analysis unit and is used for sending the fault distance to a power distribution main station; the power supply unit is used for supplying power to the transient filtering device. According to the invention, the impedance in the distribution line is analyzed, so that the fault point can be accurately positioned, the fault inspection time of workers is shortened, and the timeliness of fault processing is improved.

Description

Technical Field

[0001] This application relates to the field of power distribution network safety technology, and more specifically to a transient filtering device and a transient filtering system suitable for dual-power distribution networks. Background Technology

[0002] In distribution network power supply systems employing a typical dual-power supply model, the power supply radius of the distribution lines is excessively long and contains numerous branches. When a fault occurs in the line, it is necessary to quickly and accurately locate the fault point. Currently, the main methods for fault location in distribution lines in related technologies include the following two: 1. Traveling wave ranging method: This method uses the principle that traveling waves reflect off the fault point to locate the fault. However, the traveling wave signal under fault conditions is a sudden, singular signal containing a large number of high-frequency components. Furthermore, the propagation speed and attenuation rate of the traveling wave vary under different modes, making it difficult to determine the arrival time of the traveling wave. Moreover, the transmission speed of the traveling wave is approximately equal to the speed of light, meaning that an error of 1μs can result in an error of 150m, which is detrimental to the accurate location of the fault point. 2. Impedance ranging method: This method uses the change in line impedance between the fault point and the measurement point to calculate the fault distance. However, the impedance ranging method in related technologies has a large error in detecting the fault point, increasing the fault inspection time. Summary of the Invention

[0003] The present invention is proposed to solve at least one of the above-mentioned problems. According to a first aspect of this application, a transient filtering device suitable for a dual-power supply distribution network is provided, comprising: a data acquisition unit, a data analysis unit, a data transmission unit, and a power supply unit; the data acquisition unit is used to acquire electrical quantity signals of the distribution line and convert the electrical quantity signals into digital signals; the data analysis unit is connected to the data acquisition unit and is used to analyze the impedance in the distribution line based on the digital signals to determine the fault distance; the data transmission unit is connected to the data analysis unit and is used to send the fault distance to the distribution master station; the power supply unit is used to supply power to the transient filtering device.

[0004] Optionally, the data analysis unit is specifically used to: solve the single-ended fault impedance distance expression based on the digital signal to obtain the fault distance; wherein, the dual-power supply distribution network includes a first power source and a second power source, and the fault distance represents the distance from the fault point to the first power source or the second power source.

[0005] Optionally, the expression for single-ended fault impedance ranging is: Where Z represents the measured impedance of the first or second power supply side, z represents the impedance per unit distance of the conductor, and D f R represents the distance to the fault. fC represents the transition resistance at the fault point. m I represents the real part of the fault current distribution coefficient. g The fault component of the measured current on the first power supply or the second power supply side is represented by y, the angle of the fault current distribution coefficient is represented by y, and the total current of the measured current on the first power supply or the second power supply side is represented by I.

[0006] Optionally, solving the single-ended fault impedance distance expression includes: decomposing the real and imaginary parts of the measured impedance and calculating the fault distance by combining the impedance angle of the distribution line.

[0007] Alternatively, the measured impedance can be decomposed using the following formula:

[0008]

[0009] Where X represents the measured reactance of the first power supply or the second power supply side, R represents the measured reactance of the first power supply or the second power supply side, and α L The impedance angle of the power distribution line is represented by x, which represents the reactance per unit distance of the conductor.

[0010] Optionally, the power supply unit includes a CT energy harvesting module and a solar power supply module; the CT energy harvesting module is used to inductively harvest power from the power distribution line; the solar power supply module is used to convert solar energy into electrical energy; wherein, at least one of the CT energy harvesting module and the solar power supply module supplies power to the transient filter device.

[0011] Optionally, the data acquisition unit includes: a high-speed FPGA data acquisition module, used to acquire and convert the electrical quantity signal using high-speed sampling technology; wherein, the high-speed FPGA data acquisition module includes a Rogowski coil and an FPGA submodule, the Rogowski coil is used to acquire the electrical quantity signal of the power distribution line, and the FPGA submodule is used to convert the electrical quantity signal into the digital signal.

[0012] Optionally, the data transmission unit includes a wireless radio frequency module and a GPRS module; the wireless radio frequency module is used for short-range communication with the power distribution master station via wireless radio frequency communication; the wireless radio frequency module is used for long-range communication with the power distribution master station via GPRS communication.

[0013] Optionally, the transient filtering device suitable for dual-power supply distribution networks further includes: a wire clamping spring and an anti-slip pad; the wire clamping spring is used to fix the transient filtering device on the distribution line; the anti-slip pad is used to increase the friction between the transient filtering device and the distribution line.

[0014] According to a second aspect of this application, a transient filtering system suitable for a dual-power supply distribution network is provided, comprising: a power distribution master station and the aforementioned transient filtering device suitable for a dual-power supply distribution network.

[0015] This invention has at least one of the following technical effects:

[0016] The transient filtering device and system provided by this invention, applicable to dual-power distribution networks, can accurately locate fault points by analyzing the impedance in the distribution lines, shortening the fault inspection time for staff and improving the timeliness of fault handling. Simultaneously, it reduces the time and scope of power outages due to faults, helping to improve the overall power supply reliability of the distribution network and meeting users' needs for stable power supply. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the 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.

[0018] Figure 1 This is a schematic diagram of the transient filtering device for a dual-power supply distribution network provided in the first embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of the dual-power supply distribution network provided in the first embodiment of the present invention;

[0020] Figure 3(a) is a schematic diagram of the Rogowski coil in the open state in the transient filtering device suitable for dual-power supply distribution network provided in the first embodiment of the present invention;

[0021] Figure 3(b) is a schematic diagram of the structure of the transient filter device for dual-power supply distribution network provided in the first embodiment of the present invention, in which the Rogowski coil is in a closed state;

[0022] Figure 4 This is a schematic diagram of the transient filtering system for a dual-power supply distribution network provided in the first embodiment of the present invention;

[0023] Figure 5 This is a schematic diagram showing the installation location of a transient filtering device suitable for a dual-power supply distribution network, according to an embodiment of the present invention.

[0024] Figure 6 This is a topology diagram of a test circuit provided in an embodiment of the present invention. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the present invention more apparent, exemplary embodiments according to the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are merely a part of the embodiments of the present invention, and not all of the embodiments of the present invention. It should be understood that the present invention is not limited to the exemplary embodiments described herein. Based on the embodiments of the present invention described herein, all other embodiments obtained by those skilled in the art without inventive effort should fall within the protection scope of the present invention.

[0026] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid obscuring the invention.

[0027] It should be understood that the invention can be embodied in various forms and should not be construed as being limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0028] To fully understand this invention, a detailed structure will be presented in the following description to illustrate the technical solution proposed by this invention. Optional embodiments of the invention are described in detail below; however, in addition to these detailed descriptions, the invention may have other embodiments.

[0029] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0030] The first aspect of this application provides a transient filtering device 10 suitable for dual-power supply distribution networks, such as... Figure 1 As shown, it includes: a data acquisition unit 101, a data analysis unit 102, a data transmission unit 103, and a power supply unit 104.

[0031] The data acquisition unit 101 is used to acquire electrical quantity signals of the power distribution line and convert the electrical quantity signals into digital signals.

[0032] Among them, electrical quantity signals can be current signals or voltage signals.

[0033] As an example, a voltage signal can be converted into a digital signal using an analog-to-digital converter.

[0034] The data analysis unit 102 is connected to the data acquisition unit 101 and is used to analyze the impedance in the power distribution line based on digital signals to determine the fault distance.

[0035] As an example, the fault distance can be determined by single-ended fault impedance ranging, which reduces the influence of transition resistance and improves the accuracy of fault location.

[0036] The data transmission unit 103 is connected to the data analysis unit 102 and is used to send the fault distance to the power distribution master station.

[0037] As an example, the distance to the fault can be transmitted to the distribution master station via fiber optic or wireless channels.

[0038] The power supply unit 104 is used to supply power to the transient filter device 10.

[0039] The transient filtering device 10 for dual-power distribution networks in this embodiment analyzes the impedance in the distribution lines, enabling precise location of fault points, shortening the fault inspection time for staff, and improving the timeliness of fault handling. Simultaneously, it reduces the time and scope of power outages due to faults, helping to improve the overall power supply reliability of the distribution network and meeting users' needs for stable power supply.

[0040] In some embodiments, the data analysis unit 102 is specifically used to: solve the single-ended fault impedance distance expression based on the digital signal to obtain the fault distance.

[0041] In this context, a dual-power supply distribution network includes a first power source and a second power source, and the fault distance represents the distance from the fault point to either the first or second power source.

[0042] As an example, assuming a 10kV distribution line is a uniform line, under various fault types, the line impedance from the power source to the fault point is proportional to the line distance, and distributed capacitance is neglected. Figure 2 As shown, E1 and E2 represent the electromotive forces of the first and second power supplies, respectively, and Z1 and Z2 represent the impedances of the first and second power supply sides, respectively. R f D represents the transition resistance at the fault point. f This indicates the fault distance from the fault point to the first power source. The fault distance can be determined by solving the single-ended fault impedance distance expression using the acquired digital signal, which facilitates timely inspection and handling of faults by staff.

[0043] Specifically, the expression for single-ended fault impedance ranging is:

[0044] Where Z represents the measured impedance of the first or second power source side, z represents the impedance per unit distance of the conductor, and D f R represents the distance to the fault. f C represents the transition resistance at the fault point. m I represents the real part of the fault current distribution coefficient. gThe fault component of the measured current on the first or second power supply side is represented by y, the angle of the fault current distribution coefficient is represented by y, and the total current of the measured current on the first or second power supply side is represented by I.

[0045] It should be noted that the impedance per unit distance z of the conductor is related to the line type (e.g., LGJ-185), and the unit is ohms per kilometer (Ω / km). In a 10kV line, this parameter can be determined through the physical characteristics of the line. For example, in a 10kV LGJ-185 line, the impedance parameters k (the reactance per kilometer of conductor) and r (the resistance per kilometer of conductor) are 0.335Ω / km and 0.27Ω / km, respectively.

[0046] In this embodiment, a transition resistance R is introduced. f Fault current distribution coefficient C m The method and its correction terms can directly compensate for the interference of the transition resistance on the measured impedance Z in the mathematical model, reduce the impact of the transition resistance on the ranging accuracy, and improve the accuracy of fault location. Meanwhile, in a dual-power supply system, the fault current may come from either the first or second power supply. Traditional single-ended impedance ranging methods may produce large errors due to the influence of the end power supply. This application, by establishing a linear relationship between the measured impedance and the impedance per unit distance, can distinguish the influence of both power supplies on the fault current, thereby improving the accuracy of fault location.

[0047] In some embodiments, solving the single-ended fault impedance distance expression includes: decomposing the real and imaginary parts of the measured impedance and calculating the fault distance by combining the impedance angle of the distribution line.

[0048] Specifically, the measured impedance is decomposed using the following formula:

[0049]

[0050] Where X represents the measured reactance on the first or second power supply side, R represents the measured reactance on the first or second power supply side, and α L The impedance angle of the power distribution line is represented by x, which represents the reactance per unit distance of the conductor, i.e., the reactance per kilometer of conductor.

[0051] As an example, such as Figure 2 As shown, when calculating the fault distance from the fault point to the first power source, the collected data can be substituted into the single-ended fault impedance distance measurement expression. Then, by further processing the expression, we obtain its real part and imaginary part, which are represented by the following equations:

[0052]

[0053] Finally, the fault distance D is quickly calculated. f.

[0054] In this embodiment, by decomposing the measured impedance into real and imaginary parts and establishing a mathematical relationship using the inherent impedance angle of the line, the coupling effect of the transition resistance and the line impedance can be separated, thereby reducing the interference of the transition resistance on the fault distance calculation and meeting the rapid location requirements of complex fault scenarios in dual power supply systems.

[0055] In some embodiments, the power supply unit 104 includes a CT (Current Transformer) energy harvesting module and a solar power supply module.

[0056] The CT power harvesting module is used to inductively extract power from the power distribution line.

[0057] As an example, the CT power harvesting module can be based on the principle of electromagnetic induction, and form a current transformer by using the power harvesting iron core 201 and the wound coil. When the power distribution line current flows through the power harvesting iron core 201, the alternating magnetic field induces an electromotive force in the secondary coil, which is then converted into a usable DC power supply after rectification, filtering and voltage stabilization.

[0058] Solar power modules are used to convert solar energy into electrical energy.

[0059] As an example, a solar power module may include a solar panel, an energy storage battery, and a charge / discharge management circuit. Exemplarily, the solar panel converts solar energy into direct current (DC) electricity, the charge / discharge management circuit controls the solar panel's charging of the battery, and the charge / discharge management circuit can also control the energy storage battery's discharge as needed.

[0060] The transient filter device 10 is powered by at least one of the CT energy harvesting module and the solar power supply module.

[0061] It should be noted that when the current in the line needs to be greater than 3A, a solar power supply module is selected to provide power to ensure the normal operation of the transient filter device 10.

[0062] In this embodiment, the transient filter device 10 is powered by the CT power harvesting module and the solar power supply module. In the event of failure of one power source, the other power source can still maintain the operation of the transient filter device 10, thereby improving the redundancy and power supply continuity of the transient filter device 10.

[0063] In some embodiments, the data acquisition unit 101 includes a high-speed FPGA (Field Programmable Gate Array) data acquisition module, used to acquire and convert electrical signals using high-speed sampling technology.

[0064] The high-speed FPGA data acquisition module includes a Rogowski coil 202 and an FPGA submodule. The Rogowski coil 202 is used to acquire electrical signals from the power distribution line, and the FPGA submodule is used to convert the electrical signals into digital signals.

[0065] As an example, the data acquisition unit 101 may also include an electric field sensing element 203 for determining the energized state and voltage signal of the line.

[0066] Specifically, the Rogowski coil 202 measures the line current through the principle of electromagnetic induction and converts the large current signal into a proportional voltage signal. The electric field sensor 203 collects the induced electromotive force of the line to help determine the line's energized state and voltage signal. The FPGA submodule uses a field-programmable gate array chip to sample the signals output by the Rogowski coil 202 and the electric field sensor 203 at high speed and converts the analog signal into a digital signal through the built-in analog-to-digital converter.

[0067] In this embodiment, high-precision and high-speed sampling can be achieved by using a high-speed FPGA data acquisition module, thereby improving the accuracy and speed of data acquisition.

[0068] In some embodiments, the data transmission unit 103 includes a wireless radio frequency module and a GPRS (General Packet Radio Service) module.

[0069] The wireless radio frequency module is used for short-range communication with the power distribution station via wireless radio frequency communication.

[0070] It should be noted that the wireless radio frequency module supports short-range low-power communication, which is suitable for real-time data exchange in local areas of power distribution lines.

[0071] The wireless radio frequency module is used for remote communication with the power distribution master station via GPRS.

[0072] It should be noted that the GPRS module can achieve remote wide-area coverage through cellular networks, ensuring that fault distance information can be transmitted to the power distribution master station across complex geographical environments.

[0073] In this embodiment, the wireless radio frequency module and GPRS module can meet the communication needs of multiple scenarios and improve the reliability of the transient filter device 10.

[0074] In some embodiments, as shown in Figures 3(a)-(b), the transient filter device 10 suitable for dual-power supply distribution networks further includes: a wire clamping spring 204 and an anti-slip pad 205. The wire clamping spring 204 is used to fix the transient filter device 10 to the distribution line. The anti-slip pad 205 is used to increase the friction between the transient filter device 10 and the distribution line.

[0075] As an example, the transient filter device 10 suitable for dual-power distribution networks also includes a phase sequence identifier 206, a transparent lower cover 207, an upper outer shell 208, a closing spring 209, a nameplate 210, and a power flow direction 211.

[0076] In this embodiment, the transient filter device 10 can be securely installed on the power distribution line by using the clamping spring 204 and the anti-slip pad 205.

[0077] In addition, this application provides a transient filtering system 1 suitable for dual-power supply distribution networks, such as... Figure 4 As shown, it includes: a power distribution master station 20 and the aforementioned transient filtering device 10 suitable for dual-power supply distribution networks.

[0078] As an example, the fault range can be initially determined by the power distribution master station 20 through automation, and then the fault point can be accurately located by the transient filter device 10 suitable for dual-power supply distribution networks.

[0079] As another example, the transient filter 10 suitable for dual-power supply distribution networks can be installed at the following key nodes: each outgoing line direction on the first pole, the poles containing the section switches of the main line near the power supply side, the outlets of large branch lines, and both sides of the crossing cable, etc. Taking the LGJ-185 line as an example, such as... Figure 5 As shown in the figure, the triangle represents the installation position of the transient filter device 10 suitable for dual-power supply distribution networks.

[0080] It is worth mentioning that the transient filter device 10 can be installed using either the ground potential working method or the intermediate potential working method. Intermediate potential working method: The operator uses an insulated bucket truck, achieving complete insulation between the operator and the ground through the truck's insulated platform, and then uses an insulated operating rod for live installation, thus isolating the operator from the ground and the live conductor. Ground potential working method: When the insulated bucket truck cannot access the site, the operator climbs a pole to reach a position that meets the safety distance requirements for a 10kV distribution network line, and then uses an insulated operating rod to install the new transient filter device 10. That is, the operator is at ground potential, and the insulated operating rod is used to indirectly contact the live equipment.

[0081] Next, as Figure 6 As shown, taking a short-circuit fault in phase B of a test line's outgoing branch as an example, the workflow of the transient filtering system 1 applicable to a dual-power supply distribution network is explained: First, the fault range can be preliminarily determined to be between test line / 7501 side pole and test line / 7420 side pole; then, data is collected and the location of the fault point is determined by the transient filtering device 10 near test line / 7501 side pole, confirming that the fault location is near side pole 7417; finally, the precise location of the fault point is sent to the distribution master station 20.

[0082] The transient filtering system 1 of this embodiment, applicable to a dual-power distribution network, can accurately locate fault points by analyzing the impedance in the distribution lines and promptly transmit the fault information to the distribution master station 20. This facilitates real-time monitoring and analysis of the distribution network's operational status by staff, improving the timeliness of fault handling. Simultaneously, it reduces the time and scope of power outages due to faults, contributing to improved overall power supply reliability of the distribution network and meeting users' demands for stable power supply.

[0083] Although exemplary embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above exemplary embodiments are merely illustrative and are not intended to limit the scope of this application. Various changes and modifications can be made therein by those skilled in the art without departing from the scope and spirit of this application. All such changes and modifications are intended to be included within the scope of this application as claimed in the appended claims.

[0084] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0085] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed.

[0086] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of this application may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0087] Similarly, it should be understood that, in order to streamline this application and aid in understanding one or more of the various inventive aspects, features of this application may sometimes be grouped together in a single embodiment, figure, or description thereof in the description of exemplary embodiments of this application. However, this approach should not be construed as reflecting an intention that the claimed application requires more features than are expressly recited in each claim. Rather, as reflected in the corresponding claims, its inventive point lies in solving the corresponding technical problem with features fewer than all features of a single disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of this application.

[0088] Those skilled in the art will understand that, apart from the mutual exclusion of features, all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or units of any method or apparatus so disclosed can be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature that serves the same, equivalent, or similar purpose.

[0089] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

[0090] The various component embodiments of this application can be implemented in hardware, or as software modules running on one or more processors, or a combination thereof. Those skilled in the art will understand that microprocessors or digital signal processors (DSPs) can be used in practice to implement some or all of the functions of some modules according to the embodiments of this application. This application can also be implemented as an apparatus program (e.g., a computer program and computer program product) for performing part or all of the methods described herein. Such an implementation of this application can be stored on a computer-readable medium, or can be in the form of one or more signals. Such signals can be downloaded from an Internet website, provided on a carrier signal, or provided in any other form.

[0091] It should be noted that the above embodiments are illustrative of this application and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. This application can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

[0092] The above description is merely a specific embodiment or illustration of the embodiments of this application. The scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. The scope of protection of this application shall be determined by the scope of the claims.

Claims

1. A transient filtering device suitable for dual-power supply distribution networks, characterized in that, include: Data acquisition unit, data analysis unit, data transmission unit, and power supply unit; The data acquisition unit is used to acquire electrical quantity signals of the power distribution line and convert the electrical quantity signals into digital signals; The data analysis unit is connected to the data acquisition unit and is used to analyze the impedance in the power distribution line based on the digital signal to determine the fault distance. The data transmission unit is connected to the data analysis unit and is used to send the fault distance to the power distribution master station; The power supply unit is used to supply power to the transient filter device.

2. The transient filtering device for dual-power supply distribution networks according to claim 1, characterized in that, The data analysis unit is specifically used to: solve the single-ended fault impedance ranging expression based on the digital signal to obtain the fault distance; The dual-power supply distribution network includes a first power source and a second power source, and the fault distance refers to the distance from the fault point to the first power source or the second power source.

3. The transient filtering device for dual-power supply distribution networks according to claim 2, characterized in that, The expression for single-ended fault impedance ranging is: Where Z represents the measured impedance of the first or second power supply side, z represents the impedance per unit distance of the conductor, and D f R represents the distance to the fault. f C represents the transition resistance at the fault point. m I represents the real part of the fault current distribution coefficient. g The fault component of the measured current on the first power supply or the second power supply side is represented by y, the angle of the fault current distribution coefficient is represented by y, and the total current of the measured current on the first power supply or the second power supply side is represented by I.

4. The transient filtering device for dual-power supply distribution networks according to claim 3, characterized in that, Solving the expression for single-ended fault impedance ranging includes: The real and imaginary parts of the measured impedance are decomposed, and the fault distance is calculated by combining the impedance angle of the power distribution line.

5. The transient filtering device for dual-power supply distribution networks according to claim 4, characterized in that, The measured impedance can be decomposed using the following formula: Where X represents the measured reactance of the first power supply or the second power supply side, R represents the measured reactance of the first power supply or the second power supply side, and α L The impedance angle of the power distribution line is represented by x, which represents the reactance per unit distance of the conductor.

6. The transient filtering device for dual-power supply distribution networks according to claim 1, characterized in that, The power supply unit includes a CT energy harvesting module and a solar power supply module; The CT energy harvesting module is used to inductively harvest power from the power distribution line; The solar power module is used to convert solar energy into electrical energy; The transient filter is powered by at least one of the CT energy harvesting module and the solar power supply module.

7. The transient filtering device for dual-power supply distribution networks according to claim 1, characterized in that, The data acquisition unit includes: a high-speed FPGA data acquisition module, used to acquire and convert the electrical quantity signals using high-speed sampling technology; The high-speed FPGA data acquisition module includes a Rogowski coil and an FPGA submodule. The Rogowski coil is used to acquire electrical signals of the power distribution line, and the FPGA submodule is used to convert the electrical signals into digital signals.

8. The transient filtering device for dual-power supply distribution networks according to claim 1, characterized in that, The data transmission unit includes a wireless radio frequency module and a GPRS module; The wireless radio frequency module is used to conduct short-range communication with the power distribution master station via wireless radio frequency communication. The wireless radio frequency module is used to communicate remotely with the power distribution master station via GPRS communication.

9. The transient filtering device for dual-power supply distribution networks according to claim 1, characterized in that, Also includes: Wire clamping springs and anti-slip pads; The clamping spring is used to fix the transient filter device on the power distribution line; The anti-slip pad is used to increase the friction between the transient filter device and the power distribution line.

10. A transient filtering system suitable for dual-power supply distribution networks, characterized in that, include: The power distribution master station and the transient filtering device suitable for dual-power supply distribution networks as described in any one of claims 1-9.

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