Tower fault current detection device and design method

Abstract

The utility model relates to a kind of tower fault current detection device and design method, it is related to power system transmission and distribution technical field;Real-time, reliable monitoring to power grid operating state can be realized.The tower fault current detection device includes: openable and closable Rogowski coil sensor, signal conditioning unit, measurement and control unit;The openable and closable Rogowski coil sensor is sleeved on single or multiple tower foot of tower, for inducting tower fault current, generates induced electromotive force;The input of signal conditioning unit is connected with the two output ends of the Rogowski coil sensor, for the protection, amplification processing of inductive electromotive force signal output by sensor;The input of measurement and control unit is connected with the output of signal conditioning unit, for analog voltage signal after processing, whether fault occurs is determined by analog voltage signal, generates fault alarm signal when fault occurs.

Description

Technical Field

[0001] This application relates to the field of power system transmission and distribution technology, and in particular to a tower fault current detection device and design method. Background Technology

[0002] With the rapid development of the national economy and the continuous expansion of the power system, transmission lines, as the arteries of power transmission, are of paramount importance for their safe and stable operation. Transmission line towers are key facilities supporting overhead lines. When a short-circuit fault to ground occurs due to lightning strikes, external damage, insulation aging, or other reasons, a huge fault current will flow into the ground through the tower itself. Timely and accurate detection and location of these fault currents are of great significance for quickly isolating faulty sections, preventing the accident from escalating, ensuring power grid safety, and guiding line inspection and maintenance.

[0003] Currently, the traditional method for detecting fault currents in transmission line towers mainly relies on connecting current transformers (CTs) in series with the tower's grounding down conductor. However, this method has significant limitations: First, the installation process requires a power outage, necessitating the disconnection of the grounding down conductor before the CT can be connected in series. This is not only complex and costly but also directly impacts the reliability of the power grid. Second, traditional electromagnetic CTs suffer from magnetic saturation, making it difficult to accurately measure transient fault currents containing a large DC component, leading to decreased measurement accuracy. Furthermore, the enormous energy in the fault current may damage the CT itself connected in series.

[0004] To overcome the shortcomings of traditional CT (Computed Tomography) devices, non-contact measurement technologies have gradually been applied. Among them, the Rogowski coil has become an excellent choice due to its advantages such as good linearity, no magnetic saturation, wide measurement range, and fast response speed. However, directly applying standard Rogowski coils to tower fault current detection still faces challenges: on the one hand, the tower base structure is bulky, making it impossible to directly install a closed-loop coil on-site. Disassembling the tower base for installation would also lead to power outages, negating the advantages of non-contact measurement. On the other hand, fault current detection devices are usually installed on towers in the field or even remote areas, and providing them with a long-term, stable, and maintenance-free power supply is a major technical challenge. Solar panels are prone to dust accumulation and obstruction, while lithium batteries require frequent replacement, resulting in high maintenance costs. Summary of the Invention

[0005] This application provides a tower fault current detection device and design method, which can detect the fault current of transmission line towers in a non-contact and easy-to-install manner, so as to realize real-time and reliable monitoring of the power grid operation status.

[0006] In a first aspect, this application provides a tower fault current detection device, comprising: Openable Rogowski coil sensor, signal conditioning unit, measurement and control unit; The openable Rogowski coil sensor is mounted on one or more legs of the tower to sense the fault current of the tower and generate an induced electromotive force. The input terminal of the signal conditioning unit is connected to the two output terminals of the Rogowski coil sensor, and is used to protect and amplify the induced electromotive force signal output by the sensor. The input terminal of the measurement and control unit is connected to the output terminal of the signal conditioning unit, and is used to acquire the processed analog voltage signal, determine whether a fault has occurred through the analog voltage signal, and generate a fault alarm signal when a fault occurs.

[0007] The tower fault current detection device provided in this embodiment uses an openable Rogowski coil sensor to perform non-contact measurement of the tower fault current. This device is easy to install, requiring no power outage during installation, thus improving construction convenience and ensuring power grid reliability. The signal conditioning unit protects and amplifies the induced electromotive force signal, accurately reconstructing the fault current signal and ensuring measurement accuracy. The measurement and control unit can determine whether a fault has occurred and issue a fault alarm. The overall device combines accuracy and reliability with automation and intelligence, providing a more advanced and effective means for monitoring the condition of transmission lines.

[0008] For example, the frame of the closable Rogowski coil sensor is made of non-ferromagnetic material and has an openable ring structure that can be fitted onto the base of a tower. The frame is uniformly and symmetrically wound with N turns of wire to form a coil; when the current-carrying conductor of the tower passes perpendicularly through the center of the circular frame and the current flowing through it changes, according to Faraday's law of electromagnetic induction, an induced electromotive force proportional to the rate of change of the measured current will be generated at both ends of the coil.

[0009] The cross-sectional area S and the equivalent radius R of the openable Rogowski coil sensor are expressed as follows:

[0010] Where d is the inner diameter of the coil, D is the outer diameter of the coil, and h is the thickness of the coil.

[0011] The relationship between the fault current i(t) and the induced electromotive force e(t) is as follows:

[0012] In the formula, i(t) is the fault current, H is the magnetic field strength, B is the magnetic induction intensity, R is the radius of the loop coil, μ0 is the permeability of free space, Φ is the magnetic flux hinged by a single turn of the coil, Ψ is the total magnetic flux linkage, N is the number of turns of the coil winding, and S is the cross-sectional area of ​​the coil.

[0013] For example, the number of turns N in the coil winding is determined by the coil cross-sectional area S and the equivalent radius R:

[0014] i(t) is the fault current, e(t) is the induced electromotive force, and μ0 is the vacuum permeability.

[0015] Specifically, the signal conditioning unit includes a limiting protection circuit, an integrating amplifier circuit, and an impedance matching circuit; The limiting protection circuit is used to suppress transient overvoltages and protect downstream devices; the integrating amplifier circuit is used to restore the induced electromotive force signal to an analog voltage signal proportional to the fault current amplitude; the impedance matching circuit is used to improve the signal carrying capacity and reduce transmission loss.

[0016] Specifically, the measurement and control unit performs digital filtering and RMS calculation on the collected analog voltage signal to obtain the fault current measurement value; when the fault current measurement value exceeds the preset threshold, a fault is determined to have occurred, and the fault alarm signal and the information of the tower where it is located are sent to the remote monitoring center.

[0017] Specifically, the power supply module includes a wind energy harvesting device, a power management circuit, and an energy storage unit; The wind energy harvesting device converts ambient wind energy into electrical energy; the power management circuit is connected to the wind energy harvesting device and is used to rectify, stabilize, and regulate the AC power output by the wind energy harvesting device to convert it into DC power; the energy storage unit is connected to the power management circuit and is used to store excess electrical energy.

[0018] Specifically, the tower fault current detection device also includes a wireless communication unit, which receives fault alarm signals transmitted by the measurement and control unit and sends the fault alarm signals to the remote monitoring center via wireless communication.

[0019] Secondly, this application provides a method for detecting fault current in a steel tower, including: An openable Rogowski coil sensor is mounted on one or more legs of a transmission line tower to sense the fault current flowing through the tower and generate an induced electromotive force signal that is proportional to the rate of change of the current. The induced electromotive force signal is subjected to amplitude limiting protection, integral amplification and impedance matching processing to restore it into an analog voltage signal that is proportional to the fault current amplitude. The fault current measurement value is calculated based on the simulated voltage signal; The calculated fault current measurement value is compared with the preset fault current threshold. If the fault current measurement value exceeds the fault current threshold, a fault is determined to have occurred, and a fault alarm signal is generated. If the fault current measurement value does not exceed the fault current threshold, no fault is determined, and monitoring continues.

[0020] Thirdly, this application provides an electronic device including a memory and one or more processors. The memory stores one or more computer programs, each including instructions that, when executed by the processor, cause the electronic device to perform the tower fault current detection method as described in the first aspect.

[0021] Fourthly, this application provides a computer-readable storage medium storing instructions that, when executed on an electronic device, cause the electronic device to perform the tower fault current detection method as described in the first aspect.

[0022] Fifthly, this application provides a computer program product that, when run on an electronic device, causes the electronic device to perform the tower fault current detection method as described in the first aspect.

[0023] Understandably, the beneficial effects achieved by the application monitoring devices, electronic devices, computer-readable storage media, and computer program products provided above can be referred to the beneficial effects in the first aspect, and will not be repeated here. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of the tower fault current detection device provided in the embodiments of this application; Figure 2 This is a schematic diagram of the magnetic ring coil in the tower fault current detection device provided in the embodiments of this application; Figure 3 A schematic flowchart of the tower fault current detection method provided in the embodiments of this application; Figure 4 This is another schematic flowchart of the tower fault current detection method provided in the embodiments of this application; Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0025] To facilitate a clear description of the technical solutions in the embodiments of this application, the terms "first" and "second" are used in the embodiments of this application to distinguish identical or similar items with substantially the same function and effect. For example, "first chip" and "second chip" are only used to distinguish different chips and do not limit their order. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and the terms "first" and "second" do not necessarily imply that they are different. It should be noted that in the embodiments of this application, the words "exemplary" or "for example" are used to indicate that they are examples, illustrations, or descriptions. Any embodiment or design scheme described as "exemplary" or "for example" in this application should not be construed as being better or more advantageous than other embodiments or design schemes. Specifically, the use of the words "exemplary" or "for example" is intended to present the relevant concepts in a specific manner. In the embodiments of this application, "at least one" means one or more, and "more than one" means two or more.

[0026] It should be noted that "at the time of..." in the embodiments of this application can be either at the instant when a certain situation occurs, or for a period of time after the occurrence of a certain situation. The embodiments of this application do not make specific limitations on this.

[0027] The implementation of this embodiment will now be described in detail with reference to the accompanying drawings.

[0028] This embodiment provides a tower fault current detection device for detecting fault current in transmission line towers.

[0029] Figure 1 A schematic diagram of the structure of the tower fault current detection device provided in an embodiment of this application is shown.

[0030] like Figure 1 As shown, the tower fault current detection device may include an openable Rogowski coil sensor, a signal conditioning unit, a measurement and control unit, and a power supply module. Its working principle is as follows: Openable Rogowski coil sensors are installed on the four legs of the transmission line tower to be detected. When a fault current flows through the tower, an induced electromotive force is generated. This induced electromotive force is processed and transmitted to the measurement and control unit, which calculates the fault current measurement value. When the fault current measurement value exceeds a preset threshold, a fault is determined to have occurred, and a fault alarm signal is generated, completing the online monitoring and location of tower insulation faults.

[0031] This openable Rogowski coil sensor is mounted on one or more legs of a steel tower to sense fault currents and generate induced electromotive force.

[0032] The input terminal of the signal conditioning unit is connected to the two output terminals of the Rogowski coil sensor, and is used to protect and amplify the induced electromotive force signal output by the sensor.

[0033] The input terminal of the measurement and control unit is connected to the output terminal of the signal conditioning unit to acquire the processed analog voltage signal, determine whether a fault has occurred through the analog voltage signal, and generate a fault alarm signal when a fault occurs.

[0034] The power supply module is used to provide operating power for the signal conditioning unit and the measurement and control unit.

[0035] Specifically, the frame of the closable Rogowski coil sensor is made of non-ferromagnetic material and has an openable circular ring structure that can be fitted onto the base of the tower. N turns of wire are evenly and symmetrically wound on the frame to form a coil. When the current-carrying conductor of the tower passes perpendicularly through the center of the circular frame and the current flowing through it changes, according to Faraday's law of electromagnetic induction, an induced electromotive force proportional to the rate of change of the measured current will be generated at both ends of the coil.

[0036] Figure 2 The structure of an openable Rogowski coil sensor is shown. (Example) Figure 2 As shown, the Rogowski coil sensor employs an openable hinge structure for easy mounting and fixing onto the tower surface. In use, the Rogowski coil can be opened via the hinge, fitted onto the tower base, and then the hinge can be closed to form a complete circular structure. The parameters of the Rogowski coil can be set according to the actual conditions of the transmission line tower. For example, for transmission line towers, the tower base typically uses 12cm to 20cm angle steel. In this embodiment, the Rogowski coil is designed with an inner diameter d = 16cm, an outer diameter D = 18cm, and a thickness h = 2cm.

[0037] Based on the aforementioned design parameters of the openable Rogowski coil sensor—namely, inner diameter, outer diameter, and thickness—the cross-sectional area S and the equivalent coil radius R can be calculated. The specific formula is: (1) In the formula, d is the inner diameter of the coil, D is the outer diameter of the coil, and h is the thickness of the coil.

[0038] After determining the coil cross-sectional area S and equivalent radius R, the number of turns N in the coil winding is determined using the coil cross-sectional area S and equivalent radius R: (2) i(t) is the fault current, e(t) is the induced electromotive force, and μ0 is the vacuum permeability.

[0039] In this embodiment, considering both the fault current detection range and the manufacturing cost of the Rogowski coil, the number of coil turns satisfies:

[0040] The permeability of free space, .

[0041] For example, the fault current typically ranges from 100A to 1000A (RMS). If the induced electromotive force is at least 10mV when the fault current is at its minimum of 100A, then the following calculations can be performed based on the law of electromagnetic induction:

[0042] Based on the known parameters, the magnitudes of parameters such as the average radius R, the current cross-sectional area S, and the free permeability μ0 can be determined, as shown below:

[0043]

[0044] Once the material and dimensions of the magnetic ring coil are designed, the number of turns of the coil winding can be designed according to the current sensitivity requirements, as shown below:

[0045] When N=480 turns, the actual mutual inductance coefficient is:

[0046] When the minimum effective value of the fault current is 100A, the magnitude of the induced electromotive force is:

[0047] When the minimum effective value of the fault current is 100A, its induced electromotive force is 10.24mV, which can be effectively detected by subsequent measurement circuits.

[0048] Similarly, when the maximum effective value of the fault current is 1000A, according to the above calculation method, the induced electromotive force when N is 480 turns is:

[0049] The signal conditioning unit includes a limiting protection circuit, an integrating amplifier circuit, and an impedance matching circuit. The limiting protection circuit is used to suppress transient overvoltages and protect downstream devices. The integrating amplifier circuit is used to restore the induced electromotive force signal to a voltage signal proportional to the fault current amplitude. The impedance matching circuit is used to improve the signal carrying capacity and reduce transmission loss.

[0050] The limiting protection circuit can use a bidirectional Zener diode or a fast recovery diode for clamping. When the signal is within the normal range, the diode is reverse cut off or slightly conducting, and the signal can pass through without attenuation. When there is a transient overvoltage, the diode breaks down in reverse, and the transient overvoltage of the fault is clamped within a safe range, dissipating excess energy and protecting downstream devices.

[0051] Alternatively, the limiting protection circuit can be implemented using an operational amplifier. A diode or Zener diode is connected in series in the feedback network of the operational amplifier. When the output exceeds the threshold, the Zener diode turns on, limiting the output voltage amplitude, thereby ensuring that the output voltage does not exceed the threshold.

[0052] The induced electromotive force (EMF) signal is a differential signal that varies with time. An integrating amplifier circuit can use the charging and discharging accumulation effect of a capacitor to restore the differential signal to a DC voltage signal proportional to the original current amplitude. In this embodiment, an active integrating circuit is constructed to integrate the induced EMF output from the Rogowski coil, which is proportional to di / dt, and restore it to a voltage signal proportional to the fault current amplitude. Simultaneously, the weak signal is amplified, and a feedback resistor suppresses DC drift.

[0053] The goal of impedance matching circuits is to ensure that the output impedance of the signal source meets the maximum power transfer condition with the load impedance. Impedance mismatch between the source and load leads to signal reflection or voltage drop losses. The principle of impedance matching circuits is to use impedance transformation (such as a transformer) or buffer amplification (voltage follower) to bring the equivalent load of the signal source closer to its internal resistance, preventing excessive signal absorption or reflection by the load. Impedance transformation is achieved through voltage followers or emitter followers, with high input impedance receiving the signal from the previous stage and low output impedance driving the subsequent measurement unit, reducing transmission loss and distortion.

[0054] Specifically, the measurement and control unit performs digital filtering and RMS calculation on the collected analog voltage signal to obtain the fault current measurement value; when the fault current measurement value exceeds the preset threshold, a fault is determined to have occurred, and the fault alarm signal and the information of the tower where it is located are sent to the remote monitoring center.

[0055] Digital filtering refers to using filters to remove interference signals from the acquired signals and retain the valid signals, thereby improving the accuracy of current detection.

[0056] Effective value calculation refers to calculating the fault current using the analog voltage signal output by the signal conditioning unit. The formula for calculating the measured fault current value based on the analog voltage signal is as follows: (3) Where R is the equivalent radius of the switchable Rogowski coil, N is the number of turns in the coil winding, μ0 is the free permeability, and U... Rm It is an analog voltage signal.

[0057] like Figure 1 As shown, the tower fault current detection device may also include a wireless communication unit connected to the measurement and control unit for communication with a remote monitoring center. The wireless communication unit can receive fault alarm signals and tower information from the measurement and control unit, and transmit these signals to the remote monitoring center wirelessly.

[0058] The measurement and control unit operates in a low-power sleep mode, performing current measurements via periodic wake-up to reduce overall system power consumption. When the current measurement result from the measurement and control unit indicates no fault has occurred, the wireless communication unit remains inactive; when the current measurement result indicates a fault has occurred, the wireless communication unit activates. When the wireless communication unit is activated and requires peak power support, the energy storage unit serves as the main power source.

[0059] The power supply module includes a wind energy harvesting device, a power management circuit, and an energy storage unit. The wind energy harvesting device converts ambient wind energy into electrical energy. The power management circuit is connected to the wind energy harvesting device and is used to rectify, stabilize, and regulate the AC power output by the wind energy harvesting device to convert it into DC power. The energy storage unit is connected to the power management circuit and is used to store excess electrical energy.

[0060] In this embodiment, the energy storage unit can be a battery or a supercapacitor. When the wireless communication unit is activated and requires peak power support, the energy storage unit serves as the main power source. When the measurement and control unit is in sleep mode and the wireless communication unit is not activated, the entire device can be powered by a wind-powered energy harvesting device, thereby reducing power consumption. By combining a wind-powered energy harvesting self-powered system with intelligent power management, the long-term power supply problem for field equipment is effectively solved. Combined with a low-power design, the device achieves maintenance-free operation, improves reliability, and reduces dimensional complexity.

[0061] Furthermore, this embodiment also provides a method for detecting tower fault current, which can be applied to the aforementioned tower fault current detection device. For example... Figure 3 As shown, the method for detecting fault current in a steel tower specifically includes: Step 101: Install the openable Rogowski coil sensor on one or more legs of the transmission line tower to sense the fault current flowing through the tower and generate an induced electromotive force signal that is proportional to the rate of change of the current.

[0062] Step 102: Perform amplitude limiting protection, integral amplification and impedance matching processing on the induced electromotive force signal to restore it to an analog voltage signal that is proportional to the fault current amplitude.

[0063] Step 103: Calculate the fault current measurement value based on the simulated voltage signal. The specific calculation formula is as follows:

[0064] Where R is the equivalent radius of the switchable Rogowski coil, N is the number of turns in the coil winding, μ0 is the permeability of free space, and U... Rm It is an analog voltage signal.

[0065] This embodiment also performs digital filtering on the analog voltage signal to remove interference signals and obtain an effective analog voltage signal. Then, the effective value of the current is calculated using the effective analog voltage signal to obtain the fault current measurement value, thereby improving the accuracy of current measurement.

[0066] Step 104: Compare the calculated fault current measurement value with the preset fault current threshold. If the fault current measurement value exceeds the fault current threshold, a fault is determined to have occurred, and a fault alarm signal is generated. If the fault current measurement value does not exceed the fault current threshold, no fault is determined, and monitoring continues.

[0067] The fault current threshold is set according to actual conditions. If the measured fault current exceeds the threshold, a fault is confirmed, and a fault alarm signal is generated. The fault alarm signal is used to alert the user of the fault and can consist of text, voice, images, or a combination thereof. The fault alarm signal can be transmitted to the remote monitoring center via a wireless communication unit. The wireless communication unit can also transmit the fault alarm signal along with information about the faulty transmission line tower to the remote monitoring center, where the fault information is recorded for easy fault resolution.

[0068] In this embodiment, a non-contact measurement of tower fault current is achieved using an openable Rogowski coil sensor. Installation requires no power outage, greatly improving construction convenience and grid reliability. The induced electromotive force signal is acquired via the openable Rogowski coil, and the fault current signal is accurately reconstructed using integration amplification and impedance matching processing. The measured fault current value is then calculated, and the occurrence of a fault is determined based on this value. The combination of high-speed acquisition and intelligent judgment ensures measurement accuracy and rapid response, exhibiting high reliability, high precision, and intelligent features.

[0069] When the above-mentioned method for detecting tower fault current is applied to a tower fault current detection device, the execution process is as follows: Figure 4 As shown, it specifically includes the following: Step 401: Install the openable Rogowski coil sensor on one or more legs of the transmission line tower to sense the fault current flowing through the tower and generate an induced electromotive force. Step 402: The signal conditioning unit performs amplitude limiting protection, integral amplification and impedance matching processing on the induced electromotive force signal to restore it to an analog voltage signal that is proportional to the fault current amplitude. Step 403: The measurement and control unit acquires the analog voltage signal at high speed, performs digital filtering and RMS value calculation, and obtains the fault current measurement value; Step 404: Determine whether the current measurement value exceeds the threshold. If yes, generate a fault alarm signal; otherwise, return to step 403, and the measurement and control unit continues monitoring.

[0070] Step 405: The wireless communication module uploads the fault alarm signal and the corresponding tower information.

[0071] The fault current measurement principle of the above-mentioned tower fault current detection method is described in detail in the corresponding tower fault current detection device, so it will not be repeated here.

[0072] This application also provides an electronic device. Figure 5 A schematic diagram of the structure of an electronic device suitable for implementing embodiments of the present disclosure is shown. Figure 5 The electronic device 600 shown is merely an example and should not be construed as limiting the functionality and scope of use of the embodiments disclosed herein.

[0073] like Figure 5 As shown, the electronic device 600 includes a central processing unit (CPU) 601, which can perform various appropriate actions and processes based on a program stored in a read-only memory (ROM) 602 or a program loaded from a storage section 608 into a random access memory (RAM) 603. The RAM 603 also stores various programs and data required for system operation. The CPU 601, ROM 602, and RAM 603 are interconnected via a bus 604. An input / output (I / O) interface 605 is also connected to the bus 604.

[0074] The following components are connected to I / O interface 605: an input section 606 including a keyboard, mouse, etc.; an output section 607 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and speakers, etc.; a storage section 608 including a hard disk, etc.; and a communication section 609 including a network interface card such as a LAN card, modem, etc. The communication section 609 performs communication processing via a network such as the Internet. A drive 610 is also connected to I / O interface 605 as needed. A removable medium 611, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed on drive 610 as needed so that computer programs read from it can be installed into storage section 608 as needed.

[0075] In particular, according to embodiments of this disclosure, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this disclosure include a computer program product comprising a computer program carried on a computer-readable storage medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via communication section 609, and / or installed from removable medium 611. When the computer program is executed by central processing unit (CPU) 601, it performs the functions defined in the embodiments of this application.

[0076] For example, when the computer program is executed by the central processing unit (CPU) 601, it can perform the following: An openable Rogowski coil sensor is mounted on one or more legs of a transmission line tower to sense the fault current flowing through the tower and generate an induced electromotive force (EMF) signal proportional to the rate of change of the current. The induced EMF signal is then subjected to amplitude limiting protection, integral amplification, and impedance matching to restore it to an analog voltage signal proportional to the magnitude of the fault current. The fault current measurement value is calculated based on the analog voltage signal. This calculated fault current measurement value is compared with a preset fault current threshold. If the fault current measurement value exceeds the threshold, a fault is detected, and a fault alarm signal is generated. If the fault current measurement value does not exceed the threshold, no fault is detected, and monitoring continues.

[0077] It should be noted that the computer-readable medium disclosed herein may be a computer-readable signal medium or a computer-readable storage medium, or any combination thereof. A computer-readable storage medium may be, for example,—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this disclosure, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In this disclosure, a computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. Computer-readable signal media can also be any computer-readable medium other than computer-readable storage media, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to: wireless, wire, optical fiber, RF, etc., or any suitable combination thereof.

[0078] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, may be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0079] The units described in the embodiments of this disclosure can be implemented in software or hardware, and the described units can also be located in a processor. The names of these units do not necessarily limit the unit itself.

[0080] In another aspect, this application also provides a computer-readable medium, which may be included in the electronic device described in the above embodiments; or it may exist independently and not assembled into the electronic device. The computer-readable medium carries one or more programs, which include instructions that, when executed by the electronic device, cause the electronic device to perform the methods described in the above embodiments.

[0081] It should be noted that although several modules or units for the device used to perform actions have been mentioned in the detailed description above, this division is not mandatory. In fact, according to the embodiments of this application, the features and functions of two or more modules or units described above can be embodied in one module or unit. Conversely, the features and functions of one module or unit described above can be further divided and embodied by multiple modules or units.

[0082] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A fault current detection device for iron towers, characterized in that, include: Openable Rogowski coil sensor, signal conditioning unit, measurement and control unit, power supply module; The openable Rogowski coil sensor is mounted on one or more legs of the tower to sense the fault current of the tower and generate an induced electromotive force. The input terminal of the signal conditioning unit is connected to the two output terminals of the Rogowski coil sensor, and is used to protect and amplify the induced electromotive force signal output by the sensor. The input terminal of the measurement and control unit is connected to the output terminal of the signal conditioning unit, and is used to acquire the processed analog voltage signal, determine whether a fault has occurred through the analog voltage signal, and generate a fault alarm signal when a fault occurs. The power supply module is used to provide operating power for the signal conditioning unit and the measurement and control unit.

2. The tower fault current detection device according to claim 1, characterized in that, The frame of the openable Rogowski coil sensor is made of non-ferromagnetic material and has an openable ring structure that can be fitted onto the base of the tower. The frame is uniformly and symmetrically wound with N turns of wire to form a coil; when the current-carrying conductor of the tower passes perpendicularly through the center of the circular frame and the current flowing through it changes, according to Faraday's law of electromagnetic induction, an induced electromotive force proportional to the rate of change of the measured current will be generated at both ends of the coil.

3. The tower fault current detection device according to claim 2, characterized in that, The cross-sectional area S and the equivalent radius R of the openable Rogowski coil sensor are expressed as follows: Where d is the inner diameter of the coil, D is the outer diameter of the coil, and h is the thickness of the coil.

4. The tower fault current detection device according to claim 1, characterized in that, The relationship between the fault current i(t) and the induced electromotive force e(t) is as follows: In the formula, i(t) is the fault current, H is the magnetic field strength, B is the magnetic induction intensity, R is the radius of the loop coil, μ0 is the permeability of free space, Φ is the magnetic flux hinged by a single turn of the coil, Ψ is the total magnetic flux linkage, N is the number of turns of the coil winding, and S is the cross-sectional area of ​​the coil.

5. The tower fault current detection device according to claim 3, characterized in that, Also includes: The number of turns N in the coil winding is determined by the coil cross-sectional area S and the equivalent radius R: i(t) is the fault current, e(t) is the induced electromotive force, and μ0 is the vacuum permeability.

6. The tower fault current detection device according to claim 1, characterized in that, The signal conditioning unit includes a limiting protection circuit, an integrating amplifier circuit, and an impedance matching circuit; The limiting protection circuit is used to suppress transient overvoltages and protect downstream devices; the integrating amplifier circuit is used to restore the induced electromotive force signal to an analog voltage signal proportional to the fault current amplitude; the impedance matching circuit is used to improve the signal carrying capacity and reduce transmission loss.

7. The tower fault current detection device according to claim 1, characterized in that, The measurement and control unit performs digital filtering and RMS calculation on the acquired analog voltage signal to obtain the fault current measurement value; When the measured fault current exceeds the preset threshold, a fault is determined to have occurred, and the fault alarm signal and the information of the tower where it is located are sent to the remote monitoring center.

8. The tower fault current detection device according to claim 1, characterized in that, The power supply module includes a wind energy harvesting device, a power management circuit, and an energy storage unit; The wind energy harvesting device converts ambient wind energy into electrical energy; the power management circuit is connected to the wind energy harvesting device and is used to rectify, stabilize, and regulate the AC power output by the wind energy harvesting device to convert it into DC power; the energy storage unit is connected to the power management circuit and is used to store excess electrical energy.

9. A method for detecting fault current in iron towers, characterized in that, include: An openable Rogowski coil sensor is mounted on one or more legs of a transmission line tower to sense the fault current flowing through the tower and generate an induced electromotive force signal that is proportional to the rate of change of the current. The induced electromotive force signal is subjected to amplitude limiting protection, integral amplification and impedance matching processing to restore it into an analog voltage signal that is proportional to the fault current amplitude. The fault current measurement value is calculated based on the simulated voltage signal; The calculated fault current measurement value is compared with the preset fault current threshold. If the fault current measurement value exceeds the fault current threshold, a fault is determined to have occurred, and a fault alarm signal is generated. If the measured fault current value does not exceed the fault current threshold, it is determined that there is no fault and monitoring continues.

10. The method for detecting fault current in iron towers according to claim 9, characterized in that, The formula for calculating the fault current measurement value based on the analog voltage signal is as follows: Where R is the equivalent radius of the switchable Rogowski coil, N is the number of turns in the coil winding, μ0 is the permeability of free space, and U... Rm It is an analog voltage signal.

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