Device and method for measuring wind deflection motion attitude of insulator string of power transmission line
Technical Field
The invention relates to the technical field of transmission line safety, in particular to a device and a method for measuring wind deflection movement postures of a transmission line insulator string.
Background
The windage yaw and vibration generated by the high wind on the insulator string, especially the insulator string with large tonnage, can generate strong stress change on the pole tower. Insulator strings are important component equipment for line transmission, play a role in hanging, supporting conducting wires and insulating, and the insulator strings of domestic 10-750 kV power transmission lines with different voltage grades have great difference in the aspects of structure, manufacturing level, operating conditions, using quantity and the like, so that in recent years, flashover and damage accidents related to the insulator strings are increased day by day, and the accidents mainly include flashover, reduction of mechanical strength, string falling, breakdown, brittle failure, deterioration, external force damage and the like.
The influence of irregular swing caused by windage yaw on the service life of an insulator string is not negligible, particularly in areas with large wind sand, the windage yaw of the insulator string of the power transmission line causes a phase-to-ground insulation gap to be smaller than the minimum gap distance under power frequency voltage, and flashover discharge causes electric erosion marks or internal burns on the local surface of the insulator string, so that the insulation performance and the mechanical performance of the insulator string are reduced, and the influence on the safe and stable operation of a high-voltage transmission line and the service life of facilities is large. In the windy area, when the wind speed is higher than a certain level and is relatively stable, the insulator string of the line can swing violently, when the swing amplitude and frequency are accumulated to a certain degree and the duration is relatively long, the internal structure of the insulator string is damaged and broken, meanwhile, the hardware connection part is damaged or falls due to long-term friction, the insulator string or a lead is broken away from the insulator string, serious accidents such as power failure or personal injury and death are caused, and the safety operation of a power grid is seriously threatened.
Therefore, the swing amplitude and the swing frequency are correctly identified, the stress change is analyzed, the service life of the insulator string is estimated, and the method has important significance for guaranteeing safe operation and maintenance of the insulator string.
Disclosure of Invention
The invention provides a device and a method for measuring wind deflection movement attitude of an insulator string of a power transmission line, aiming at the technical problems in the prior art, and solving the problem that the swing amplitude and frequency of the insulator string cannot be identified in real time in the prior art.
The technical scheme for solving the technical problems is as follows: the utility model provides a transmission line insulator chain windage yaw motion gesture measuring device, includes: the system comprises a video online monitoring device and an image processing and identifying unit; the video online monitoring device is arranged at the bottom of the tower, the direction of a camera of the video online monitoring device is an oblique upward direction, and a video image of the insulator string during online operation is collected and sent to the image processing and identifying unit; and the image processing and identifying unit calculates the displacement of the insulator string in the space and corresponding time information based on high-speed visual dynamic measurement.
A measuring method of the measuring device comprises the following steps:
step 1, the video online monitoring device collects video images of the insulator string during online operation and sends the video images to the image processing and identifying unit;
and 2, calculating the displacement of the insulator string in the space and corresponding time information by the image processing and identifying unit based on high-speed visual dynamic measurement.
The invention has the beneficial effects that: the visual camera is used for collecting video images of the insulator string during online operation, the non-contact visual image processing technology is used for automatically monitoring the swing of the insulator string, the frequency, the direction and the amplitude of the swing of the insulator string and the stress condition are calculated and judged through the analysis and the processing of an image processing algorithm, the hidden danger is early warned in advance, the online monitoring level of a line is improved, and the safe and stable operation of a power grid is guaranteed.
On the basis of the technical scheme, the invention can be further improved as follows.
Further, the process of measuring and calculating the displacement of the insulator string in space by the image processing and recognition unit comprises the following steps:
setting a reference distance in the video image, calculating a spatial distance by establishing a relation between a pixel point and the reference distance, and calculating the displacement of the insulator string in the space according to the spatial distance measurement.
Further, the set reference distance is the string length of the insulator string, and the pixel points are wire spacers.
Further, the measuring device also comprises a wireless communication module and a power supply module;
the power supply module provides electric energy for the measuring device in a solar energy or energy storage mode;
after the displacement of the insulator string in the space and the corresponding time information are obtained through measurement and calculation of each measuring device, the displacement and the corresponding time information are sent to an external central processing system through the wireless communication module;
and the central processing system determines the maximum swing amplitude, horizontal and vertical displacement and vibration frequency of the insulator string according to the displacement of the insulator string in the space and corresponding time information, and sends out early warning information when the windage yaw motion of the insulator string exceeds a set range.
The optical lens focuses visible light on a visible light image sensor CMOS, a visible light channel is driven by the CMOS and data are collected, then the visible light channel passes through a processing circuit, image processing is carried out by a DSP, and processed data are obtained. And then the data is sent to a background central processing system by a communication interface circuit.
Further, the step 2 of calculating the displacement of the insulator string in space comprises:
step 201, measuring a pixel point position S of a conductor spacer in a video when a distance between a video shooting point and the conductor spacer is 10m0;
Step 202, calculating the distance between the insulator string and the video monitoring point in the state of being vertical to the ground
Wherein S is
Measuring ADRepresenting the pixel point position of the conductor spacer in the video when the insulator string is in a state of being vertical to the ground;
step 203, calculating the distance between the insulator string and the video monitoring point when the insulator string moves to the farthest state due to windage yaw
Wherein S is
Measuring ACRepresenting the pixel point position of the conductor spacer in the video when the insulator string moves to the farthest end state under the windage yaw;
step 204, calculating the wind deflection angle of the insulator string:
wherein l
BEThe distance between the end point of the cross arm and the highest point of the tower is represented as l
ABRepresenting the distance from the cross arm end point to the video online monitoring device,
l
AEthe distance l from the highest point of the tower to the video online monitoring device is represented
BCIndicating the string length of the insulator string.
Further, the process of determining the pixel position of the spacer in the video in the step 201-203 includes:
and setting the RGB represented color range of the conductor spacer, and identifying the conductor spacer through the set color range in the image processing and identifying process.
Further, step 4 is followed by:
and 5, determining the maximum swing amplitude, horizontal and vertical displacement and vibration frequency of the insulator string according to the displacement of the insulator string in the space and corresponding time information, and sending out early warning information when the windage yaw motion of the insulator string exceeds a set range.
The beneficial effect of adopting the further scheme is that: the installation and maintenance are convenient, and the device is far away from a strong electric field area; because this device is installed on the pole tower body of tower, keeps away from strong electric field area, is convenient for install and maintain, and the communication of device receives the interference of discharging for a short time, is favorable to reducing communication module's power. The energy taking mode is various, and the power supply reliability is high; because the device is arranged on the tower body and the tower body, the space for energy taking and energy storage is large, the device is firmly arranged, the limitation of the operation of the wire of the power transmission line on the volume and the weight of the device can be avoided, and the influence of the vibration of the wire on the operation reliability of the device can be avoided. Acquiring multi-dimensional information of windage yaw, galloping and the like of the insulator; by obtaining the displacement and time information of the wire and the insulator in the space, the information such as the maximum swing amplitude, the horizontal and vertical displacement, the vibration frequency and the like of the insulator can be obtained, and a basis is provided for the analysis of the failure or damage mechanism of the insulator under strong wind or breeze. Reducing the transmission amount of data; the device processes video information of the insulator windage yaw swing, extracts useful characteristic information, and the image recognition adopts RGB three-dimensional color gradient calculation, so that the memory and calculation time consumed by the image recognition are reduced, the transmission of massive video information is avoided, the traffic cost of communication is reduced on one hand, and the power consumption of a communication module is reduced on the other hand.
Drawings
Fig. 1 is an installation schematic diagram of an embodiment of a video online monitoring device provided by the present invention;
fig. 2 is a schematic structural diagram of an embodiment of a device for measuring wind deflection movement attitude of an insulator string of a power transmission line provided by the invention;
FIG. 3 is a schematic circuit diagram of an embodiment of an image processing and recognition unit according to the present invention;
FIG. 4 is a schematic circuit diagram of an embodiment of a processor of an image processing and recognition unit according to the present invention;
fig. 5 is a schematic diagram of an embodiment of determining spatial displacement of an insulator string by the device for measuring the windage yaw movement attitude of the insulator string of the power transmission line provided by the invention.
Detailed Description
The principles and features of this invention are described below in conjunction with the following drawings, which are set forth by way of illustration only and are not intended to limit the scope of the invention.
The invention provides a device for measuring wind deflection motion attitude of an insulator string of a power transmission line, which comprises: the device comprises a video online monitoring device and an image processing and identifying unit. Fig. 1 is a schematic installation diagram of an embodiment of an online video monitoring device according to the present invention.
As can be seen from fig. 1, the video online monitoring device is arranged at the bottom of the tower, the direction of a camera of the video online monitoring device is an oblique upward direction, so that the insulator string is in a shooting range during movement, and a video image of the insulator string during online movement is collected and sent to the image processing and recognition unit.
And the image processing and identifying unit calculates the displacement of the insulator string in the space and corresponding time information based on high-speed visual dynamic measurement.
According to the device for measuring the windage yaw movement attitude of the insulator string of the power transmission line, the video image of the insulator string during online operation is acquired through the visible light camera, the swinging of the insulator string is automatically monitored by adopting a non-contact visible light image processing technology, the frequency, the direction and the amplitude of the swinging of the insulator string and the stress condition are calculated and judged through the analysis and processing of an image processing algorithm, the early warning is carried out on hidden dangers, the online monitoring level of the line is improved, and the safe and stable operation of a power grid is guaranteed. The device can also be popularized and applied to the measurement of the vibration characteristics of the icing galloping of the transmission line tower and the ground wire.
Example 1
Embodiment 1 provided by the present invention is an embodiment of a device for measuring a windage yaw movement attitude of an insulator string of a power transmission line provided by the present invention, and as shown in fig. 2, fig. 2 is a schematic structural diagram of an embodiment of a device for measuring a windage yaw movement attitude of an insulator string of a power transmission line provided by the present invention, and as can be seen from fig. 2, the device for measuring a windage yaw movement attitude of an insulator string of a power transmission line includes: the device comprises a video online monitoring device and an image processing and identifying unit. The video on-line monitoring device is arranged at the bottom of the tower, the direction of a camera of the video on-line monitoring device is the direction which is inclined upwards, specifically, the direction of the camera can be the direction which forms an included angle of 45 degrees with a horizontal line, and the insulator string is located in the shooting range during movement. And collecting video images of the insulator strings during online running and sending the video images to the image processing and identifying unit.
And the image processing and identifying unit calculates the displacement of the insulator string in the space and corresponding time information based on high-speed visual dynamic measurement.
The process of measuring and calculating the displacement of the insulator string in space by the image processing and identifying unit comprises the following steps:
setting a reference distance in the video image, calculating the distance of a space by establishing the relation between the pixel point and the reference distance, and calculating the displacement of the insulator string in the space according to the distance measurement of the space. The reference distance of the setting is the string length of the insulator string, and the pixel points are wire spacing rods.
The digital image processing technology can realize high-precision calibration and error correction of the shooting system, deformation in one or two directions is usually measured in actual measurement, and an optical system adopts a square standard component calibration method: namely, the accurate size of the standard component is corresponding to the pixel coordinate of the CCD image of the standard component, and the calibration matrix parameter is calculated.
Preferably, the measuring device further comprises a wireless communication module and a power supply module.
The power supply module provides electric energy for the measuring device in a solar energy or energy storage mode.
After the displacement of the insulator string in the space and the corresponding time information are obtained through measurement and calculation by each measuring device, the displacement and the corresponding time information are sent to an external central processing system through a wireless communication module.
The central processing system determines the maximum swing amplitude, horizontal and vertical displacement and vibration frequency of the insulator string according to the displacement of the insulator string in the space and corresponding time information, and sends out early warning information when the windage yaw motion of the insulator string exceeds a set range.
The optical lens focuses visible light on a visible light image sensor CMOS, a visible light channel is driven by the CMOS and data are collected, then the visible light channel passes through a processing circuit, image processing is carried out by a DSP, and processed data are obtained. And then the data is sent to a background central processing system by a communication interface circuit.
As shown in fig. 3, which is a schematic circuit diagram of an embodiment of an image processing and recognition unit according to the present invention, according to the requirement of a system for signal processing, a circuit needs to implement driving and signal preprocessing of a visible light image sensor, and real-time processing of image data, a large-scale field programmable logic array FPGA is adopted, an SRAM buffer is adopted at the periphery, the large-scale field programmable logic array is adopted, the number of internal logic units, IO ports, and the RAM capacity all meet the requirement, and two external SRAMs are used for image temporary storage.
FIG. 4 is a schematic circuit diagram of an embodiment of a processor of an image processing and recognition unit provided by the present invention, wherein the FPGA is internally driven by RAW/RGB888, a clock and reset module, an SDRAM controller, FIFO1, FIFO2, and VGA. The clock and reset module is used for providing different clock signals and reset signals of each module, the input clock is a 50MHz crystal oscillator clock and a CMOS image sensor clock, and the output clock is other module working clocks including a 100MHz clock, a 25MHz clock, an I2C interface clock and the like. The RAW/RGB888 module completes image format conversion, realizes conversion from Bayer array format to RGB888 format, and processes the image into each pixel to obtain total bit width of RGB three signal components of 24 bits. FIFO1 realizes data forwarding between RAW/RGB888 controllers, FIFO2 realizes data forwarding before SDRAM controller and VGA driver module. VGA drive module is used for exporting VGA video image array information display signal, and the VGA interface includes 5 signals: video field signal, video line synchronizing signal, R signal, G signal, B signal, which drive the reference clock to 25.175 MHz.
Example 2
Embodiment 2 provided by the invention is an embodiment of a measurement method of a transmission line insulator string windage yaw movement attitude measurement device provided by the invention, and as shown in fig. 5, is a schematic diagram of an embodiment of the transmission line insulator string windage yaw movement attitude measurement device provided by the invention for determining the displacement of an insulator string in space, and as can be seen from fig. 5, the measurement method is based on the transmission line insulator string windage yaw movement attitude measurement device provided by the embodiment of the invention.
Step 1, the video online monitoring device collects video images of insulator strings during online operation and sends the video images to an image processing and identifying unit.
And 2, calculating the displacement of the insulator string in the space and corresponding time information by the image processing and identifying unit based on high-speed visual dynamic measurement.
Further, the step 2 of calculating the displacement of the insulator string in space comprises:
step 201, measuring a pixel point position S of a conductor spacer in a video when a distance between a video shooting point and the conductor spacer is 10m0。
Step 202, calculating the distance between the insulator string and a video monitoring point in a state of being vertical to the ground
Wherein S is
Measuring ADAnd the positions of the pixel points of the conductor spacers in the video are represented when the insulator string is in a state of being vertical to the ground.
Step 203, calculating the distance between the insulator string and the video monitoring point when the insulator string moves to the farthest end state in windage yaw
Wherein S is
Measuring ACAnd the positions of the pixel points of the conductor spacers in the video are shown when the insulator string moves to the farthest state under the windage yaw.
Step 204, calculating the wind deflection angle of the insulator string:
wherein l
BEThe distance between the end point of the cross arm and the highest point of the tower is represented as l
ABRepresents the distance from the end point of the cross arm to the video online monitoring device,
l
AEthe distance l from the highest point of the tower to the video online monitoring device is shown
BCIndicating the string length of the insulator string.
Preferably, the process of determining the position of the pixel point of the spacer in the video in step 201 and 203 includes:
setting the color range represented by RGB (red, green and blue) of the conductor spacer, and identifying the conductor spacer through the set color range in the image processing and identifying process.
Preferably, step 4 is followed by:
and 5, determining the maximum swing amplitude, horizontal and vertical displacement and vibration frequency of the insulator string according to the displacement of the insulator string in the space and corresponding time information, and sending out early warning information when the windage yaw motion of the insulator string exceeds a set range.
The measuring method of the device for measuring the windage yaw movement attitude of the insulator string of the power transmission line is convenient to install and maintain and is far away from a strong electric field area; because this device is installed on the pole tower body of tower, keeps away from strong electric field area, is convenient for install and maintain, and the communication of device receives the interference of discharging for a short time, is favorable to reducing communication module's power. The energy taking mode is various, and the power supply reliability is high; because the device is arranged on the tower body and the tower body, the space for energy taking and energy storage is large, the device is firmly arranged, the limitation of the operation of the wire of the power transmission line on the volume and the weight of the device can be avoided, and the influence of the vibration of the wire on the operation reliability of the device can be avoided. Acquiring multi-dimensional information of windage yaw, galloping and the like of the insulator; by obtaining the displacement and time information of the wire and the insulator in the space, the information such as the maximum swing amplitude, the horizontal and vertical displacement, the vibration frequency and the like of the insulator can be obtained, and a basis is provided for the analysis of the failure or damage mechanism of the insulator under strong wind or breeze. Reducing the transmission amount of data; the device processes video information of the insulator windage yaw swing, extracts useful characteristic information, and the image recognition adopts RGB three-dimensional color gradient calculation, so that the memory and calculation time consumed by the image recognition are reduced, the transmission of massive video information is avoided, the traffic cost of communication is reduced on one hand, and the power consumption of a communication module is reduced on the other hand.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.