Overhead transmission line sag on-line monitoring device and method

Abstract

The invention discloses an overhead power transmission line sag online monitoring device and method, and relates to the field of power transmission line safe operation, and the device comprises an ultrasonic ranging unit which is used for collecting the height of a monitoring point on a power transmission line and the horizontal distance between the monitoring point and a reference tower; the angle measuring unit is used for collecting inclination angles of suspension points at two ends of the power transmission line; and the arithmetic unit is respectively connected with the ultrasonic ranging unit, the angle measuring unit and the monitoring center, and is used for calculating the sag of the power transmission line according to the power transmission line parameters obtained from the monitoring center, the height of the monitoring point, the horizontal distance between the monitoring point and the reference tower and the inclination angle, and sending the sag to the monitoring center. According to the invention, the sag change condition of the power transmission line can be monitored in real time, and operation and maintenance personnel of a power system can be timely reminded to discover and solve the sag problem by providing accurate sag data, so that the safe and stable operation of the power transmission line is ensured.

Description

Technical Field

[0001] The present application relates to the field of safe operation of power transmission lines, and in particular to an online sag monitoring device and method for overhead power transmission lines. Background Art

[0002] The sag of overhead transmission lines is an important indicator for the design and operation of transmission lines. The size of the sag is directly related to the safety of transmission line operation. Changes in the transmission capacity of the transmission line, as well as factors such as icing, strong winds, and temperature may cause changes in the sag of the transmission line. Excessive or insufficient sag may cause serious safety hazards. Reasonable control of line sag is an important measure to ensure the stable operation of transmission lines.

[0003] The current manual sag measurement method is limited by the patrol cycle and is highly dependent on personnel experience and operating skills. It has problems such as low measurement accuracy and cumbersome measurement process. Summary of the invention

[0004] The purpose of this application is to provide an online monitoring device and method for sag of overhead transmission lines, which can monitor the sag changes of transmission lines in real time, and promptly remind power system operation and maintenance personnel to discover and solve sag problems by providing accurate sag data, thereby ensuring the safe and stable operation of transmission lines.

[0005] To achieve the above objectives, this application provides the following solutions:

[0006] In a first aspect, the present application provides an overhead transmission line sag online monitoring device, comprising:

[0007] Ultrasonic distance measuring unit, used to collect the height of the monitoring point on the transmission line and the horizontal distance between the monitoring point and the reference tower;

[0008] Angle measurement unit, used to collect the inclination angles of the suspension points at both ends of the transmission line;

[0009] The operation unit is connected to the ultrasonic ranging unit, the angle measuring unit and the monitoring center respectively, and is used to calculate the sag of the transmission line according to the transmission line parameters obtained from the monitoring center, the height of the monitoring point, the horizontal distance between the monitoring point and the reference tower, and the inclination angle, and send the sag to the monitoring center.

[0010] In a second aspect, the present application provides an overhead transmission line sag online monitoring method, the method is applied to the above-mentioned overhead transmission line sag online monitoring device, the method comprising:

[0011] Collect the height of the monitoring point on the transmission line and the horizontal distance between the monitoring point and the reference tower;

[0012] Collect the inclination angles of the suspension points at both ends of the transmission line;

[0013] Obtaining transmission line parameters;

[0014] The sag of the transmission line is calculated according to the transmission line parameters, the height of the monitoring point, the horizontal distance between the monitoring point and the reference tower, and the inclination angle.

[0015] According to the specific embodiments provided in this application, this application has the following technical effects:

[0016] The present application provides an overhead transmission line sag online monitoring device and method, which installs the sag online monitoring device at any position of the transmission line, collects the height of the monitoring point and the horizontal distance from the reference tower based on an ultrasonic ranging unit, collects the inclination angle of the suspension points at both ends of the transmission line based on an angle measurement unit, and calculates the sag of the transmission line according to the transmission line parameters obtained from a monitoring center, thereby realizing real-time monitoring of the sag of the transmission line and providing accurate sag data for the monitoring center. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A schematic diagram of functional modules of an overhead transmission line sag online monitoring device provided in one embodiment of the present application;

[0019] Figure 2 It is a schematic diagram of the functional modules of the induction energy acquisition unit;

[0020] Figure 3 A schematic diagram of a flow chart of an online monitoring method for sag of an overhead transmission line provided in one embodiment of the present application;

[0021] Figure 4 Schematic diagram of the transmission line sag measurement principle. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0023] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0024] In an exemplary embodiment, Figure 1 As shown, an online monitoring device for sag of an overhead transmission line is provided, comprising: an ultrasonic distance measuring unit 1, an angle measuring unit 2 and a computing unit 3.

[0025] In a specific embodiment, the ultrasonic distance measuring unit 1 includes two distance measuring sensors, one arranged horizontally and the other arranged vertically downward, respectively collecting the horizontal distance l between the monitoring point A and the reference tower. A and height h A , expressed as A(l A ,h A ), based on the principle of ultrasonic ranging, by collecting the ultrasonic transmission and reception time t, according to It can be calculated that l A and h A , v is the speed of ultrasonic wave propagation in air, which is 340m / s.

[0026] In a specific embodiment, the angle measurement unit 2 includes two inclination sensors, which are respectively installed near the suspension points at both ends of the transmission line, and collect the inclination angles of the suspension points at both ends of the transmission line in real time, which are θ1 and θ2 respectively.

[0027] In a specific embodiment, the operation unit 3 is connected to the ultrasonic distance measuring unit 1, the angle measuring unit 2 and the monitoring center 6 respectively, and is used to calculate the sag of the transmission line according to the transmission line parameters, the height of the monitoring point, the horizontal distance between the monitoring point and the reference tower and the inclination angle obtained from the monitoring center 6, and send the sag to the monitoring center 6. The monitoring center 6 analyzes the collected information to determine whether the sag exceeds the set threshold. If an abnormal situation occurs, the status and location are automatically pushed to the operation and maintenance personnel through a pop-up window or SMS alarm, so that the operation and maintenance personnel can take emergency measures in a timely and accurate manner.

[0028] In another exemplary embodiment of the present application, Figure 1 As shown, the overhead transmission line sag online monitoring device further includes: an inductive energy acquisition unit 5, which is used to provide power for the overhead transmission line sag online monitoring device. Figure 2 As shown, the inductive energy acquisition unit 5 includes: an energy acquisition coil 51, a power control circuit 52, a voltage regulation circuit 53 and an energy storage circuit 54. The energy acquisition coil 51, the power control circuit 52, and the voltage regulation circuit 53 are connected in sequence, and the power control circuit 52 is also connected to the energy storage circuit 54.

[0029] The transmission line passes through the energy collection coil 51, which converts the electromagnetic energy induced around the transmission line into electrical energy to provide power for the equipment; the power control circuit 52 automatically adjusts the power output of the energy collection coil 51 according to the current on the transmission line, and automatically adjusts the working power in combination with the voltage level of the equipment installation; the voltage regulation circuit 53 achieves stable voltage output through rectification and filtering design, and adjusts and limits the input electrical energy in real time to ensure that the equipment can still output a stable voltage when the current is unstable; the energy storage circuit 54 stores the energy obtained by the energy collection coil 51 into the battery to ensure that the equipment can be charged and discharged correctly.

[0030] In another exemplary embodiment of the present application, Figure 1 As shown, the overhead transmission line sag online monitoring device also includes: a communication unit 4. The operation unit 3 and the monitoring center 6 perform data transmission through the communication unit 4. The communication unit 4 realizes real-time two-way transmission of data between the operation unit 3 and the monitoring center 6 through a wireless network such as GPRS / 4G / 5G / WIFI.

[0031] In a specific embodiment, the ultrasonic distance measuring unit 1, the angle measuring unit 2, the computing unit 3, the inductive energy acquisition unit 5 and the communication unit 4 are arranged in the equipment chassis, wherein the ultrasonic distance measuring unit 1 is integrated under the equipment chassis. The equipment chassis is installed on the transmission line in a clamping manner.

[0032] The sag of the transmission line must be strictly designed and regulated to ensure a sufficient safe distance from the ground and other objects, and to ensure that the line stress is within the allowable range, so as to ensure the long-term safe operation of the transmission line. The online sag monitoring device for overhead transmission lines proposed in this application can realize real-time monitoring of the sag changes of the transmission line, and can adapt to all-weather working conditions, making up for the deficiency of optical methods that cannot measure sag in harsh environments such as night and fog. By providing accurate sag data, it can promptly remind the power system operation and maintenance personnel to discover and solve sag problems, thereby ensuring the safe and stable operation of the transmission line. The device has a simple structure, small size, low cost, and is easy to miniaturize and integrate.

[0033] Based on the same inventive concept, Figure 3 As shown, the embodiment of the present application also provides an overhead transmission line sag online monitoring method, which is executed by a computer device, specifically, it can be executed by a computer device such as a terminal or a server alone, or it can be executed by a terminal and a server together. In the embodiment of the present application, the method is applied to a server as an example for explanation, including the following steps S1 to S4. Among them:

[0034] S1: Collect the height of the monitoring point on the transmission line and the horizontal distance between the monitoring point and the reference tower.

[0035] S2: Collect the inclination angles of the suspension points at both ends of the transmission line.

[0036] S3: Obtain transmission line parameters. Transmission line parameters include tower height, tower span, and insulator string length.

[0037] S4: Calculate the sag of the transmission line based on the transmission line parameters, the height of the monitoring point, the horizontal distance between the monitoring point and the reference tower, and the inclination angle. The transmission line parameters include tower height, tower span, and insulator string length.

[0038] Step S4 specifically includes: S41: constructing the parabolic equation of the transmission line and the connection equation of the suspension points at both ends of the transmission line according to the transmission line parameters, the height of the monitoring point, the horizontal distance between the monitoring point and the reference tower, and the inclination angle; S42: constructing the sag calculation equation according to the parabolic equation and the connection equation; S43: calculating the sag of the transmission line according to the sag calculation equation.

[0039] Step S41 specifically includes: correcting the coordinates of the suspension points at both ends of the transmission line according to the inclination angle, the tower height and the insulator string length; calculating the parabola equation coefficients according to the corrected coordinates of the suspension points at both ends of the transmission line, the height of the monitoring point, and the horizontal distance between the monitoring point and the reference tower; determining the connection equation coefficients according to the corrected coordinates of the suspension points at both ends of the transmission line; constructing the parabola equation of the transmission line according to the parabola equation coefficients, and constructing the connection equations of the suspension points at both ends of the transmission line according to the connection equation coefficients.

[0040] Below Figure 4 Taking the example, the online sag monitoring method for overhead transmission lines provided in this application is introduced in detail.

[0041] (1) Set tower 1 as the reference tower and establish a rectangular coordinate system. Take the intersection of tower 1 and the ground as the origin of the coordinate system. According to the obtained height and span parameters of the towers at both ends, the coordinates of the towers at both ends can be expressed as C(0,h1) and D(L,h2), where h1 and h2 are the heights of tower 1 and tower 2, respectively, and L is the span between tower 1 and tower 2.

[0042] (2) Construct the parabolic equation of the transmission line: y = ax 2 +bx+c, where y is the ordinate of any point on the transmission line, x is the abscissa of any point on the transmission line, and a, b, and c are the coefficients of the parabola equation.

[0043] (3) Construct the connection equation of the suspension points at both ends of the transmission line: y = kx + s, where k and s are the coefficients of the connection equation.

[0044] (4) Transmission lines are often suspended at a high height and have strong winds. Under the action of wind, the insulators that suspend the transmission lines are prone to deflection. Therefore, the influence of the tilt angle needs to be considered during modeling, and the coordinates of the suspension points at both ends of the transmission line need to be corrected.

[0045] The suspension point M(x1,y1) of tower No. 1 can be calculated by the following formula:

[0046] x1=d1*sinθ1;

[0047] y1=h1-d1*sinθ1;

[0048] The suspension point N(x2,y2) of tower No. 2 can be calculated by the following formula:

[0049] x2=L-d2*sinθ2;

[0050] y2=h2-d2*sinθ2;

[0051] d1 and d2 are the lengths of the insulator strings on both sides, and θ1 and θ2 are the inclination angles of the suspension points at both ends of the transmission line.

[0052] (5) According to the suspension points M(x1,y1) and N(x2,y2), the coefficients k and s of the connection equation can be calculated.

[0053]

[0054] (6) According to the data A(l A ,h A ) and the suspension points M(x1,y1) and N(x2,y2), and the parabola equation coefficients a, b, and c are calculated.

[0055]

[0056] Solve the three equations together to obtain the coefficients a, b, and c, which are as follows:

[0057]

[0058] (7) Construct the transmission line sag calculation equation: y = (kb)x-ax 2 +sc.

[0059] (8) Calculate the sag at the lowest point of the transmission line, i.e. the maximum sag f max , by differentiating the sag calculation equation, we get:

[0060] The present application installs a sag monitoring device at any position of the transmission line, collects the height of the monitoring point and its horizontal distance from the reference tower based on an ultrasonic sensor, establishes the parabolic equation of the transmission line between the two towers and the connection equation of the suspension points at both ends of the transmission line, constructs the sag calculation equation of the transmission line based on these two equations, realizes real-time monitoring of the sag of the transmission line, and realizes real-time data transmission, remote monitoring and early warning through communication methods such as 4G / 5G / WIFI.

[0061] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0062] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. An online monitoring device for sag of overhead transmission lines, characterized in that: include: Ultrasonic distance measuring unit, used to collect the height of the monitoring point on the transmission line and the horizontal distance between the monitoring point and the reference tower; Angle measurement unit, used to collect the inclination angles of the suspension points at both ends of the transmission line; The operation unit is connected to the ultrasonic ranging unit, the angle measuring unit and the monitoring center respectively, and is used to calculate the sag of the transmission line according to the transmission line parameters obtained from the monitoring center, the height of the monitoring point, the horizontal distance between the monitoring point and the reference tower, and the inclination angle, and send the sag to the monitoring center.

2. The device for online monitoring sag of overhead power transmission lines according to claim 1, characterized in that: The ultrasonic distance measuring unit includes two distance measuring sensors; the angle measuring unit includes two inclination sensors.

3. The device for online monitoring sag of overhead power transmission lines according to claim 1, characterized in that: Also includes: The inductive energy acquisition unit is used to provide power for the overhead transmission line sag online monitoring device.

4. The device for online monitoring sag of overhead power transmission lines according to claim 3, characterized in that: The inductive energy acquisition unit includes: an energy acquisition coil, a power control circuit, a voltage stabilization circuit and an energy storage circuit; the energy acquisition coil, the power control circuit and the voltage stabilization circuit are connected in sequence, and the power control circuit is also connected to the energy storage circuit.

5. The device for online monitoring sag of overhead power transmission lines according to claim 3, characterized in that: The computing unit and the monitoring center perform data transmission via a communication unit.

6. The device for online monitoring sag of overhead power transmission lines according to claim 5, characterized in that: The ultrasonic distance measuring unit, the angle measuring unit, the computing unit, the inductive energy acquisition unit and the communication unit are arranged in a device chassis, and the device chassis is installed on the transmission line in a clamping manner.

7. A method for online monitoring of sag of overhead transmission lines, characterized in that: The method is applied to the overhead transmission line sag online monitoring device according to any one of claims 1 to 6, and the method comprises: Collect the height of the monitoring point on the transmission line and the horizontal distance between the monitoring point and the reference tower; Collect the inclination angles of the suspension points at both ends of the transmission line; Obtaining transmission line parameters; The sag of the transmission line is calculated according to the transmission line parameters, the height of the monitoring point, the horizontal distance between the monitoring point and the reference tower, and the inclination angle.

8. The method for online monitoring sag of overhead power transmission lines according to claim 7, characterized in that: The sag of the transmission line is calculated according to the transmission line parameters, the height of the monitoring point, the horizontal distance between the monitoring point and the reference tower, and the inclination angle, specifically including: Constructing a parabolic equation of the transmission line and a connection equation of the suspension points at both ends of the transmission line according to the transmission line parameters, the height of the monitoring point, the horizontal distance between the monitoring point and the reference tower, and the inclination angle; Constructing a sag calculation equation according to the parabola equation and the connecting line equation; The sag of the transmission line is calculated according to the sag calculation equation.

9. The method for online monitoring sag of overhead power transmission lines according to claim 7, characterized in that: The transmission line parameters include tower height, tower spacing and insulator string length; According to the transmission line parameters, the height of the monitoring point, the horizontal distance between the monitoring point and the reference tower, and the inclination angle, the parabolic equation of the transmission line and the connection equation of the suspension points at both ends of the transmission line are constructed, specifically including: Correcting the coordinates of the suspension points at both ends of the transmission line according to the tilt angle, the tower height and the insulator string length; Calculate the parabola equation coefficients based on the coordinates of the suspension points at both ends of the transmission line after correction, the height of the monitoring point, and the horizontal distance between the monitoring point and the reference tower; Determine the connection equation coefficients according to the coordinates of the suspension points at both ends of the transmission line after correction; The parabolic equation of the transmission line is constructed according to the parabolic equation coefficients, and the connection equations of the suspension points at both ends of the transmission line are constructed according to the connection equation coefficients.

10. The method for online monitoring sag of overhead power transmission lines according to claim 7, characterized in that: The sag calculation equation is: y=(k-b)x-ax 2 +s-c Among them, y represents the ordinate of any point on the transmission line, x represents the abscissa of any point on the transmission line, a, b, c are the coefficients of the parabola equation, and k and s are the coefficients of the connection line equation.

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