CN212569004U - Fault positioning device and system of power transmission line with phase selection function - Google Patents
Fault positioning device and system of power transmission line with phase selection function Download PDFInfo
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- CN212569004U CN212569004U CN202020866313.6U CN202020866313U CN212569004U CN 212569004 U CN212569004 U CN 212569004U CN 202020866313 U CN202020866313 U CN 202020866313U CN 212569004 U CN212569004 U CN 212569004U
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Abstract
The device comprises a shell, a current sensor, an anisotropic magnetic resistance sensor, a hardware circuit and communication equipment, wherein the shell is used for being sleeved on a tower body steel frame of the power transmission line; the current sensor is coaxially arranged on the shell and used for detecting traveling wave current data of a tower body steel frame of the power transmission line; the anisotropic magnetic resistance sensor is arranged on the shell and used for detecting a synthetic magnetic field of the power transmission line, and when the anisotropic magnetic resistance sensor is installed, the anisotropic magnetic resistance sensor is positioned right below a middle phase lead of the power transmission line; the hardware circuit is connected with the current sensor and the anisotropic magnetic resistance sensor; the communication equipment is connected with the hardware circuit. The utility model provides a transmission line's fault locating device with phase selection function, when installation or maintenance fault locating device, need not to have a power failure installation and maintain, the suitability is better, also can reduce monitor terminal's quantity, reduce cost.
Description
Technical Field
The application relates to the technical field of power transmission lines, in particular to a fault positioning device and system of a power transmission line with a phase selection function.
Background
The distribution range of the overhead transmission line is wide, the geographical environment is complex, and a fault point is difficult to find when the overhead transmission line is tripped due to a fault, so that the line cannot be recovered to normally operate for a long time, economic loss is caused, and the power supply reliability is influenced. The traditional fault point inspection mode is manual inspection, but the efficiency is low, and the method depends on the experience of inspection personnel, and the method is gradually replaced along with the development of power grid intellectualization.
The application of the online monitoring and wireless communication technology obviously improves the accuracy and efficiency of fault location of the power transmission line, and the existing fault location method mainly comprises fault location protection based on a line impedance measurement principle and a protection device or a distributed fault location system based on a traveling wave location principle.
Although the fault positioning mode based on the line impedance measurement principle is low in cost and easy to implement, the fault positioning mode is greatly influenced by the system operation mode and the fault type, and the positioning accuracy is difficult to guarantee; the protection device based on the traveling wave positioning principle is divided into a single-end positioning mode and a double-end positioning mode, the single-end positioning mode is provided with less monitoring terminals, only one section of a line is provided with the monitoring terminals, the economy is higher, but the application condition is limited, and the positioning accuracy is not high when the fault characteristic is not obvious, so that the terminals are usually arranged at the two ends of the line on the line meeting the installation condition, namely, the double-end traveling wave positioning mode is adopted, so that the positioning accuracy and the anti-transition resistance capability are improved, but the method has larger positioning error when the line is longer; the distributed fault positioning system adopts a mode of installing monitoring terminals at certain intervals, well solves the problem of fault positioning of long lines, is the mode of most reliable fault positioning and highest precision at present, but has more terminals and larger investment, and the terminals are installed on a lead, so that the power failure time of the lines needs to be matched during installation and maintenance, and the workload of equipment maintenance is increased for operation and inspection personnel.
Meanwhile, the existing monitoring technology needs to arrange one monitoring terminal on each phase of conductor of the power transmission line, so that the number of the monitoring terminals required on the whole power transmission line is large, and the cost is high; the existing non-contact measurement method is difficult to solve the problem of fault phase selection.
Disclosure of Invention
The embodiment of the application provides a fault positioning device and a system of a power transmission line with a phase selection function, and aims to solve the problem that in the related art, a monitoring terminal needs to be powered off to be installed and maintained when the fault positioning device is installed or maintained, and solve the technical problems that the number of the monitoring terminals needed in the prior art is large and the cost is high.
In a first aspect, a fault location device for a power transmission line with a phase selection function is provided, which includes:
the hollow cylindrical shell is used for being sleeved on a tower body steel frame of the power transmission line;
the current sensor is coaxially arranged on the shell and used for detecting traveling wave current of a tower body steel frame of the power transmission line;
the anisotropic magnetic resistance sensor is arranged on the shell and used for detecting a synthetic magnetic field of the power transmission line, and when the anisotropic magnetic resistance sensor is installed, the anisotropic magnetic resistance sensor is positioned right below a middle phase lead of the power transmission line;
the hardware circuit is connected with the current sensor and the anisotropic magnetic resistance sensor and is used for acquiring, processing and storing traveling wave current data detected by the current sensor and synthetic magnetic field data detected by the anisotropic magnetic resistance sensor;
and the communication equipment is connected with the hardware circuit and is used for transmitting the traveling wave current data and the synthetic magnetic field data processed by the hardware circuit and synchronously timing.
In some embodiments, the anisotropic magnetoresistive sensor is a bi-directional anisotropic magnetoresistive sensor.
In some embodiments, the fault location device of the power transmission line with the phase selection function further includes a power supply for supplying power, and the power supply is connected with both the hardware circuit and the communication device.
In some embodiments, the power supply includes two power supply units and a power management circuit, the power management circuit is connected to both of the two power supply units, one of the power supply units is a battery, the other power supply unit is a solar panel, and the power management circuit is configured to select one of the power supply units to supply power to the fault location device.
In some embodiments, the power management circuit is specifically configured to: and preferentially selecting the solar panel to supply power for the fault positioning device, and selecting the battery to supply power for the fault positioning device when the solar panel cannot supply power.
In some embodiments, the battery is a rechargeable battery.
In some embodiments, the hardware circuitry comprises:
the acquisition unit is used for acquiring traveling wave current data detected by the current sensor and synthetic magnetic field data detected by the anisotropic magnetic resistance sensor;
the data processing unit is connected with the acquisition unit and is used for filtering, amplifying and converting the acquired traveling wave current data and the acquired synthetic magnetic field data;
and the storage unit is connected with the data processing unit and is used for storing the traveling wave current data and the synthetic magnetic field data processed by the data processing unit.
In some embodiments, the fault location device of the power transmission line with the phase selection function further includes a data center, which is wirelessly connected with the communication device.
In a second aspect, there is provided a fault location system for installing the fault location device, comprising:
the communication equipment of the fault positioning devices carries out wireless communication and synchronous time service;
and the data center is connected with the communication equipment of all the fault positioning devices.
The beneficial effect that technical scheme that this application provided brought includes: when the fault positioning device is installed or maintained, power failure installation and maintenance are not needed, the applicability is better, the number of monitoring terminals can be reduced, meanwhile, the realization of fault phase selection is not influenced, and the cost is reduced.
The embodiment of the application provides a fault positioning device of a power transmission line with a phase selection function, which is sleeved on a tower body steel frame of the power transmission line, the installation position is not on a wire, the device belongs to non-contact installation, double-end traveling wave positioning is realized by collecting traveling wave current entering the ground through the tower body steel frame during fault, and the fault positioning device is free from power failure installation and maintenance during installation or maintenance, and has better applicability; meanwhile, the fault positioning device comprises the anisotropic magnetic resistance sensor, the anisotropic magnetic resistance sensor is positioned under the intermediate phase lead of the power transmission line, the synthetic magnetic field of the power transmission line can be detected, the fault phase is judged through the vector change of the synthetic magnetic field, and a fault positioning device is not required to be arranged on each phase lead, so that the number of monitoring terminals can be reduced, and the cost is reduced.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
Fig. 1 is a schematic structural diagram of a fault location device of a power transmission line with a phase selection function according to an embodiment of the present application;
fig. 2 is an installation schematic diagram of a fault location device of a power transmission line with a phase selection function according to an embodiment of the present application;
FIG. 3 is a schematic diagram illustrating a magnetic field detection direction of an anisotropic magnetoresistive sensor according to an embodiment of the present application;
fig. 4 is a structural block diagram of a fault location device of a power transmission line with a phase selection function in a data transmission direction according to an embodiment of the present application;
fig. 5 is a block diagram of a fault location system provided with the fault location device according to an embodiment of the present application.
In the figure: A. a tower body steel frame; 1. a housing; 2. a current sensor; 3. an anisotropic magnetoresistive sensor; 4. a hardware circuit 4; 5. a communication device; 6. a power source; 61. a battery; 62. a solar cell panel.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
Referring to fig. 1 and 2, the embodiment of the present application provides a fault location device for a power transmission line with a phase selection function, which includes a housing 1, a current sensor 2, an anisotropic magnetic resistance sensor 3, a hardware circuit 4 and a communication device 5.
The shell 1 is a hollow cylindrical shell, the upper half part of the shell is of a non-metal structure, and the shell is used for being sleeved on a tower body steel frame A of the power transmission line; the current sensor 2 is coaxially arranged on the shell 1 and used for detecting traveling wave current of a tower body steel frame A of the power transmission line; the anisotropic magnetic resistance sensor 3 is arranged on the shell 1 and used for detecting a synthetic magnetic field of the power transmission line, and when the anisotropic magnetic resistance sensor 3 is installed, the anisotropic magnetic resistance sensor is positioned right below a middle phase lead of the power transmission line; the hardware circuit 4 is connected with the current sensor 2 and the anisotropic magnetic resistance sensor 3 and is used for acquiring, processing and storing traveling wave current data detected by the current sensor 2 and synthetic magnetic field data detected by the anisotropic magnetic resistance sensor 3; and the communication equipment 5 is connected with the hardware circuit 4 and is used for transmitting the traveling wave current data and the synthetic magnetic field data processed by the hardware circuit 4 and synchronously timing.
The working principle of the fault positioning device with the phase selection function for the power transmission line provided by the embodiment of the application is as follows:
the method comprises the following steps that a plurality of fault positioning devices are arranged on a power transmission line at intervals in advance according to the length of the power transmission line and a wiring mode, when the power transmission line breaks down, traveling wave current can be generated at a fault point, the traveling wave current is transmitted to two sides of the fault point at a speed close to the light speed, the traveling wave current on a lead can excite transient traveling wave current on a ground wire through space electromagnetic induction, the traveling wave current on each ground wire can enter the ground through a power transmission iron tower, namely the traveling wave current of the power transmission line can be monitored through the fault positioning devices arranged on a tower body steel frame of the iron tower, and the traveling wave current can;
after the fault positioning devices positioned on two sides of the fault point acquire the traveling wave current, the fault point can be accurately positioned by a double-end positioning principle according to the known distance between the two fault positioning devices and the accurate time synchronization of the two fault positioning devices.
The embodiment of the application provides a fault positioning device of a power transmission line with a phase selection function, which is sleeved on a tower body steel frame A of the power transmission line, the installation position is not on a wire, the device belongs to non-contact installation, and double-end traveling wave positioning is realized by collecting traveling wave current entering the ground through the tower body steel frame A during fault, so that power failure installation and maintenance are not needed during installation or maintenance of the fault positioning device, and the applicability is better; meanwhile, the fault positioning device comprises the anisotropic magnetic resistance sensor 3, the anisotropic magnetic resistance sensor 3 is located under the intermediate phase lead of the power transmission line, a synthetic magnetic field of the power transmission line can be detected, when the line breaks down, the vector of the synthetic magnetic field changes suddenly, the fault phase is judged through the vector change of the synthetic magnetic field, a fault positioning device does not need to be arranged on each phase lead, the number of monitoring terminals can be reduced, meanwhile, the implementation of fault phase selection is not influenced, and the cost is reduced.
Further, in the embodiment of the present application, the anisotropic magnetoresistive sensor 3 is a two-direction anisotropic magnetoresistive sensor. The anisotropic magnetic resistance sensor 3 collects the size and the direction of a three-phase lead synthesized magnetic field, and judges a fault phase according to the size and the direction of the synthesized magnetic field.
Referring to fig. 3, the anisotropic magnetic resistance sensor 3 has two magnetic field detection directions, namely a magnetic field detection direction 1 and a magnetic field detection direction 2, which can form a detection plane, and the detection plane is perpendicular to the direction of the lead when the fault location device is installed, i.e. the magnetic field along the lead is not detected. In the detection plane, the anisotropic magnetic resistance sensor 3 can detect the synthetic magnetic field of the three-phase lead, when the power transmission line operates normally, the component of the synthetic magnetic field of the three-phase lead in the detection direction 1 is very small, when the power transmission line breaks down, the vector change of the synthetic magnetic field of the three-phase lead is obvious, and the fault phase can be accurately judged according to the vector change of the synthetic magnetic field.
Furthermore, in this embodiment of the present application, the fault location device for a power transmission line with a phase selection function further includes a power supply 6 for supplying power, which is connected to both the hardware circuit 4 and the communication device 5, where the power supply 6 supplies power to the hardware circuit 4 and the communication device 5.
Specifically, in the embodiment of the present application, the power supply 6 includes two power supply units and a power management circuit, the power management circuit is connected to both the two power supply units, one of the power supply units is a battery 61, and the other power supply unit is a solar panel 62, and the power management circuit is configured to select one of the power supply units to supply power to the fault location device.
In this embodiment of the present application, the power management circuit is specifically configured to: the solar panel 62 is preferably selected to supply power to the fault location device, and when the solar panel 62 cannot supply power, the battery 61 is selected to supply power to the fault location device.
Preferably, the battery 61 is a rechargeable battery, and serves as a backup power source, when the fault location device can supply power through the solar panel 62 in a sunny day, the battery 61 is in a floating charging state, and when the fault location device cannot supply power through the solar panel 62 in a cloudy day, the battery 61 supplies power to the fault location device.
Referring to fig. 4, in the embodiment of the present application, the hardware circuit 4 includes:
an acquisition unit for acquiring traveling wave current data detected by the current sensor 2 and synthetic magnetic field data detected by the anisotropic magnetoresistive sensor 3;
the data processing unit is connected with the acquisition unit and is used for filtering, amplifying and converting the acquired traveling wave current data and the acquired synthetic magnetic field data;
and the storage unit is connected with the data processing unit and is used for storing the traveling wave current data and the synthetic magnetic field data processed by the data processing unit.
In the embodiment of the application, when the fault point is far away from the fault positioning device, the amplitude of the traveling wave current is small, so that the data processing unit is required to perform filtering, buffering, amplifying and other processing on the traveling wave current, the analog signal acquired by the sensor is converted into a digital signal which can be used for acquisition, storage and processing, and the digital signal is transmitted to the data center through the communication equipment so as to be analyzed by a worker.
Furthermore, in the embodiment of the present application, the fault location device for the power transmission line with the phase selection function further includes a data center, which is connected to the communication device 5.
Furthermore, in the embodiment of the present application, the communication device 5 is specifically configured to construct a wireless sensor network, so that data transmission can be performed between the fault location devices on the same line, and the collected traveling wave current data and the collected synthetic magnetic field data can be sent to the data center through the wireless communication network.
And the communication equipment 5 also selects a GPS or Beidou chip for synchronous time service, so that all fault positioning devices on the same line can accurately time service, and the precision of fault positioning is ensured.
Specifically, in the embodiment of the present application, the current sensor of the embodiment of the present application measures the traveling wave current by using the rogowski coil, and the rogowski coil is coaxially and fixedly arranged with the housing 1. The shell 1 of the present application needs to meet the requirement of IP65 protection level to be suitable for long-term operation on the power transmission line.
Referring to fig. 5, an embodiment of the present application further provides a fault location system with the fault location device, where the fault location system includes a plurality of fault location devices and a data center, two adjacent fault location devices are arranged at intervals, all communication devices 5 of the fault location devices perform wireless communication and synchronous time service, and the data center is connected to all the communication devices 5 of the fault location devices.
The embodiment of the application provides an install fault location system of fault location device, the fault location device who is located the fault point both sides is obtaining the travelling wave electric current after, according to two fault location device's known interval, and combine two fault location device's accurate to the time, can carry out the accurate positioning to the fault point through bi-polar location principle, need not to have a power failure to install and maintain when fault location, the suitability is better, and phase selection function has, can reduce monitor terminal's quantity, do not influence the realization of trouble phase selection simultaneously, reduce cost.
In the description of the present application, it should be noted that the terms "upper", "lower", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, which are only for convenience in describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and operate, and thus, should not be construed as limiting the present application. Unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are intended to be inclusive and mean, for example, that they may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.
It is noted that, in the present application, relational terms such as "first" and "second", and the like, are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The above description is merely exemplary of the present application and is presented to enable those skilled in the art to understand and practice the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (9)
1. A fault location device of a power transmission line with a phase selection function is characterized by comprising:
the hollow cylindrical shell (1) is sleeved on a tower body steel frame (A) of the power transmission line;
the current sensor (2) is coaxially arranged on the shell (1) and is used for detecting traveling wave current of a tower body steel frame (A) of the power transmission line;
the anisotropic magnetic resistance sensor (3) is arranged on the shell (1) and used for detecting a synthetic magnetic field of the power transmission line, and when the anisotropic magnetic resistance sensor (3) is installed, the anisotropic magnetic resistance sensor is positioned right below a middle phase lead of the power transmission line;
the hardware circuit (4) is connected with the current sensor (2) and the anisotropic magnetic resistance sensor (3) and is used for acquiring, processing and storing traveling wave current data detected by the current sensor (2) and synthetic magnetic field data detected by the anisotropic magnetic resistance sensor (3);
and the communication equipment (5) is connected with the hardware circuit (4) and is used for transmitting the traveling wave current data and the synthetic magnetic field data processed by the hardware circuit (4) and synchronously timing.
2. The fault location device of the power transmission line with the phase selection function according to claim 1, characterized in that: the anisotropic magneto-resistive sensor (3) is a bi-directional anisotropic magneto-resistive sensor.
3. The fault location device for an electric transmission line with phase selection function according to claim 1, characterized by further comprising a power supply (6) for supplying power, which is connected to both the hardware circuit (4) and the communication equipment (5).
4. The fault location device of an electric transmission line with a phase selection function according to claim 3, wherein the power source (6) comprises two power supply units and a power management circuit, the power management circuit is connected with both of the two power supply units, one of the power supply units is a battery (61), the other power supply unit is a solar panel (62), and the power management circuit is used for selecting one of the power supply units to supply power for the fault location device.
5. The apparatus according to claim 4, wherein the power management circuit is specifically configured to: the solar panel (62) is preferentially selected to be used for supplying power to the fault locating device, and when the solar panel (62) cannot supply power, the battery (61) is selected to be used for supplying power to the fault locating device.
6. The fault location device for an electric transmission line with a phase selection function according to claim 4, characterized in that the battery (61) is a rechargeable battery.
7. The fault location device of an electric transmission line with phase selection function according to claim 1, characterized in that the hardware circuit (4) comprises:
the acquisition unit is used for acquiring traveling wave current data detected by the current sensor (2) and synthetic magnetic field data detected by the anisotropic magnetic resistance sensor (3);
the data processing unit is connected with the acquisition unit and is used for filtering, amplifying and converting the acquired traveling wave current data and the acquired synthetic magnetic field data;
and the storage unit is connected with the data processing unit and is used for storing the traveling wave current data and the synthetic magnetic field data processed by the data processing unit.
8. The fault location device for transmission lines with phase selection function according to claim 1, further comprising a data center wirelessly connected to the communication equipment (5).
9. A fault location system equipped with a fault location device according to any one of claims 1 to 7, comprising:
the two adjacent fault positioning devices are arranged at intervals, and communication equipment (5) of all the fault positioning devices performs wireless communication and synchronous time service;
and the data center is connected with the communication equipment (5) of all the fault positioning devices.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020866313.6U CN212569004U (en) | 2020-05-21 | 2020-05-21 | Fault positioning device and system of power transmission line with phase selection function |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202020866313.6U CN212569004U (en) | 2020-05-21 | 2020-05-21 | Fault positioning device and system of power transmission line with phase selection function |
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| CN212569004U true CN212569004U (en) | 2021-02-19 |
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| CN202020866313.6U Active CN212569004U (en) | 2020-05-21 | 2020-05-21 | Fault positioning device and system of power transmission line with phase selection function |
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