CN107895925B - Comprehensive anti-galloping method combining limiting anti-galloping device and phase-to-ground spacer - Google Patents

Abstract

A comprehensive anti-dance method combining a limit-type anti-dance device and a phase-to-ground spacer, comprising the following steps: A. Determine the hanging point position of the phase-to-ground spacer according to the span of the transmission line; B. According to the transmission line The statistical results of the dominant wind direction in the area where the line is located can determine the installation direction of the phase-to-ground spacer; C. Determine the installation position of the limit type anti-dance device according to the gear distance and the installation position of the phase-to-ground spacer; D. Fix the limit type Anti-dancing device, adjust the length of the cable of the limit type anti-dance device, so that the cable is in a relaxed state; adjust the length of the cable between the phase-to-ground spacers to apply a pre-tightening force of 3KN to 5KN. The invention can play a good anti-dancing effect, ensure the safe operation of the transmission line, and reduce the economic loss caused by the line dancing.

Description

A comprehensive anti-dance method combining a limit-type anti-dance device and a phase-to-ground spacer

technical field

The invention belongs to the technical field of operation and maintenance of electric power system transmission lines, relates to the technical field of comprehensive prevention and control of overhead transmission line galloping, and in particular relates to a combination of a limit-type galloping prevention device applied to ultra-high voltage transmission lines and a phase-to-ground spacer bar. Anti-dance method.

Background technique

With the development of transmission lines in recent decades and the widespread construction of ultra-high voltage and ultra-high voltage lines, the probability of accidents in transmission lines is gradually increasing. Dancing is a low-frequency and large-amplitude self-excited vibration, and it moves vertically during the galloping. dominate the movement. The harm caused by dancing is also quite large, which will cause short circuit between lines and grounding short circuit. The losses caused include arc burns, broken strands, broken wires, tower damage, tower collapse, shock hammer and spacer damage. Suppressing dancing will bring serious economic losses to the country.

As the voltage level increases, the transmission line will also use split conductors with different split numbers, and the split conductors are more likely to dance. Therefore, it is necessary to urgently develop corresponding anti-dance devices for UHV and EHV lines. The existing interphase Although the spacer bar can reduce the degree of galloping to a certain extent, the interphase spacer bar will also aggravate the shear damage of the wire and the wear of the hardware. In severe cases, the interphase flashover will occur and the electrical performance will be damaged.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a comprehensive anti-dance method combining a limit-type anti-dance device and a phase-to-ground spacer to achieve the effect of anti-dance. The invention combines the limit type anti-dancing device and the phase-to-ground spacer, and at the same time exerts the functions of the phase-to-ground spacer and the limit type anti-dance device to reduce the tension of the wire when it dances, so as to achieve the effect of inhibiting or preventing the dance.

For achieving the above object, the technical scheme adopted in the present invention is:

A comprehensive anti-dance method combining a limit-type anti-dance device and a phase-to-ground spacer, characterized in that the integrated anti-dance method comprises the following steps:

Step 1: Determine the number of phase-to-ground spacers and the position of the hanging point according to the span of the transmission line;

Step 2: Check the dominant wind direction in the area where the transmission line is located, and adopt different installation measures and installation angles for the phase-to-ground spacers according to the data of the dominant wind direction;

Step 3: Determine the quantity and installation position of the limit-type anti-dance devices according to the span of the transmission line;

Step 4, fix the limit-type anti-dance device, adjust the length of the cable of the limit-type anti-dance device, so that the cable is in a relaxed state; adjust the length of the cable between the phase-to-ground spacers and apply a pre-tightening force of 3KN to 5KN.

The present invention further includes the following preferred solutions:

In step 1, when the span of the transmission line is less than or equal to 300 meters, two sets of phase-to-ground spacers shall be set; when the span of the transmission line is greater than 300 meters and less than or equal to 600 meters, three sets of phase-to-ground spacers shall be set; When the distance is greater than 600 meters and less than or equal to 800 meters, four sets of phase-to-ground spacers shall be set; among them, each group of phase-to-ground spacers includes three phase-to-ground spacers, and each phase-to-ground spacer is hung on the corresponding phase line and the ground. Between anchors, each group of phase-to-ground spacers has the same hanging point position in the horizontal direction of the transmission line.

In step 1, when the transmission line span is less than or equal to 300 meters, the hanging point positions of each group of phase-to-ground spacers in the horizontal direction of the transmission line are set at 1/3 and 2/3 of the transmission line span;

When the transmission line span is greater than 300 meters and less than or equal to 600 meters, the hanging point position of each group of phase-to-ground spacers in the horizontal direction of the transmission line is at 2/9, 1/2, and 7/9 of the transmission line span;

When the gear distance is greater than 600 meters and less than or equal to 800 meters, the hanging point position of each group of phase-to-ground spacers in the horizontal direction of the transmission line is 1/9, 1/3, 2/3, 8/9 of the transmission line distance place;

In step 2, according to the prevailing wind direction in the area where the transmission line is located, the installation measure of the phase-to-ground spacer bar is determined to be installed against the wind direction, and the installation angle is determined, that is, the angle formed by the pull-wire of the phase-to-ground spacer rod and the ground is an acute angle. The dominant wind direction is the wind direction in which the transmission lines in this region are prone to dancing season.

The installation angle is between 40° and 80°.

In step 3, corresponding to different pitches of the transmission line, the number of sets of limit-type anti-dancing devices that need to be set is the number of sets of phase-to-ground spacers corresponding to the pitch minus 1, that is: the pitch of the transmission line When the distance is less than or equal to 300 meters, a set of limit-type anti-dancing devices shall be installed; when the span is greater than 300 meters and less than or equal to 600 meters, two sets of limit-type anti-dancing devices shall be installed; when the span is greater than 600 meters and less than or equal to 800 meters At the time of installation, three sets of limit-type anti-dance devices need to be installed; among them, each group of limit-type anti-dance devices includes three limit-type anti-dance devices, and each group of limit-type anti-dance devices is located in the horizontal direction of the transmission line. The hanging point location is the same.

In step 3, the limit-type anti-dancing device and the phase-to-ground spacer bars on each phase conductor are arranged at intervals, that is, each limit-type anti-dance device is installed between two adjacent phase-to-ground spacer bars of the conductor.

In step 3, when the span of the transmission line is less than or equal to 300 meters, select the midpoint of the span of the three-phase wire to install three limit-type anti-dancing devices vertically; when the span of the transmission line is greater than 300 meters and less than or equal to 600 meters , select 1/3 and 2/3 of the three-phase wire pitch to install six limit-type anti-dancing devices vertically; when the pitch is greater than 600 meters and less than or equal to 800 meters, choose 2/9 of the three-phase wire pitch Nine limit-type anti-dancing devices are installed vertically at 1/2 and 7/9;

In step 3, an acceleration sensor for sensing the galloping speed of the wire is installed in the limit-type anti-dancing device.

In step 4, when the acceleration sensor in the limit-type anti-dancing device senses that the acceleration of the upward movement of the wire exceeds the set threshold, the limit-type anti-dancing device will automatically apply a pre-tightening force of 3KN to 5KN.

The present invention can effectively suppress the galloping by installing the phase-to-ground spacer bar and the limit-type anti-dancing device on the transmission line. At the same time, since the limit-type anti-dancing device is installed with a sensor, the cable is in a relaxed state when no galloping occurs, so it can It is very good to reduce the pulling force on the line, and the damage to the line is very small. The maximum displacement is found through modal analysis, which directly limits the vertical displacement of the galloping, and is convenient for maintenance.

Due to the difference in installation position and quantity, the phase-to-ground spacer can effectively suppress the first three-order galloping of the wire, the phase-to-ground spacer can suppress horizontal displacement and vertical displacement, and the limit-type anti-dance device can suppress vertical displacement. The step compound dance can have a good inhibitory effect, ensure the safe operation of the line, and reduce economic losses.

Description of drawings

Fig. 1 is the installation schematic diagram of the limit-type anti-dance device and the phase-to-ground spacer in the present invention;

Figure 2 is the vertical displacement diagram of the midpoint of the span before the anti-dancing device is installed;

Figure 3 is a vertical displacement diagram of the midpoint of the span after installing the limit-type anti-dance device and the phase-to-ground spacer;

Figure 4 is the wire tension diagram before the anti-dancing device is installed;

Figure 5 is the wire tension diagram after installing the limit type anti-dancing device and the phase-to-ground spacer.

Among them, 1 is the wire, 2 is the insulator string, 3 is the ground anchor, 4 is the limit type dance prevention device, and 5 is the phase-to-ground spacer bar.

Detailed ways

The technical solutions of the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

The invention discloses a comprehensive anti-dance method combining a limit-type anti-dance device and a phase-to-ground spacer, and the specific steps are as follows:

Step 1: Determine the number of phase-to-ground spacers and the position of the hanging point according to the span of the transmission line

When the span is less than 300 meters, 1/3 and 2/3 of the span are selected as the hanging point positions of the phase-to-ground spacers, and the hanging point of the limit-type anti-dancing device is set at the midpoint of the span; when the span is greater than 300 When the meter is less than 600 meters, select 2/9, 1/2 and 7/9 of the span as the hanging point position of the phase-to-ground spacer, and set the hanging point position of the limit-type anti-dancing device to 1/1 of the span. 3 and 2/3. When the span is greater than 600 meters and less than or equal to 800 meters, select 1/9, 1/3, 2/3, and 8/9 of the span as the hanging point positions of the phase-to-ground spacers, and install the limit type anti-dancing device. The hang point position is set to 2/9, 1/2 and 7/9 of the span. In the test statistics, it can be found that the amplitude of the transmission line galloping in the vertical and horizontal directions will increase with the increase of the span. When the span is less than 300 meters, it is a small span line. According to the results of the modal analysis, in the vertical In the frequency spectrum of the straight displacement and the horizontal displacement, the peak value is close to the frequency of the single half wave in the plane. Similarly, the spectrum analysis of the torsion angle is carried out. It is found in the spectrum that there is a natural frequency with the peak value close to the single half wave of the torsion. The galloping of the conductors in the distance line is mainly in the form of single and half-wave galloping in the plane; when the span is greater than 300 meters and less than 600 meters, it is a large span line at this time. There is a peak value close to the natural frequency of the single half-wave in the plane, but in the spectrum analysis of the torsion angle, it is found that there is a peak value close to the natural frequency of the third-order torsion mode of the conductor. A complex dance. Therefore, according to the results of the modal analysis, the present invention selects the hanging point positions of the phase-to-ground spacers at 1/3 and 2/3 of the gear distance when the gear distance is less than 300 meters. When the gear distance is greater than 300 meters and less than 600 meters, the The hanging point of the ground spacer is selected at 1/2 and 7/9 of the span. When the span is greater than 600 meters and less than 800 meters, the hanging point of the ground spacer is selected at 1/9 of the span. 9, 1/3, 2/3 and 7/9, which has a better effect on suppressing multi-order dancing.

Step 2: Statistically investigate the dominant wind direction in the area where the transmission line is located, and obtain the dominant wind direction in the season where the transmission line is prone to dancing, and then select the installation direction and installation angle of the phase-to-ground spacer according to the dominant wind direction. Since the phase-to-ground spacers installed in the upwind direction can act as a restraint at both ends with the limit-type anti-dance device, in most cases, the phase-to-ground spacers are installed in the upwind direction; when the wind attack angle is between 40° and 120° When , the slope of the lift coefficient of most of the conductors is negative, so the conductors may dance within the range of the wind attack angle. According to this angle, we set the installation angle of the phase-to-ground spacer between 40° and 80°.

Step 3: After installing the phase-to-ground spacer bar, install the limit-type anti-dance device according to the different spans. When the span is less than or equal to 300 meters, because the mid-point of the span is the place with the largest displacement, choose the limit-type anti-dance device. The dancing device is installed vertically at the midpoint of the span; when the span is greater than 300 meters and less than or equal to 600 meters, the limit type anti-dancing device is installed at 1/3 and 2/3 of the span according to the modal analysis results; When the distance is greater than 600 meters and less than or equal to 800 meters, limit-type anti-dancing devices shall be installed at the spans of 2/9, 1/2 and 7/9.

Step 4: Determine the hanging point position of the phase-to-ground spacer bar according to the distance in step 1, and then fix the phase-to-ground spacer bar. As shown in Figure 1, the three-phase conductors share the first-level ground anchor. After adjusting the angle of the cable, apply 3KN~ With a pre-tightening force of 5KN, due to the high probability of galloping after the wire is covered with ice, it should be considered to convert the pre-tightening force at different temperatures into the pre-tightening force at 0 degrees Celsius to ensure a good anti-dancing effect. According to the hanging point position of the limit-type anti-dance device in step 3, install the limit-type anti-dance device vertically under the wire, and adjust the cable to be in a relaxed state. The limit-type anti-dance device is a mechanical anti-dance device. And the sub-spacer is connected to the wire, and the limit type anti-dance device is installed with an acceleration sensor. When the acceleration of the upward movement of the wire exceeds a certain value, the limit type anti-dance device will automatically apply a pre-tightening force of 3KN to 5KN. When the wire moves downward, the limit-type anti-dancing device will automatically shrink the cable to restrain the dancing.

The invention combines the limit type anti-dancing device with the phase-to-ground spacer, effectively combines the phase-to-ground spacer and the limit-type anti-dance device, and gives full play to the advantages of the two. The limit-type anti-dance device can effectively Limiting the vertical displacement of the wire, the phase-to-ground spacer can effectively limit the horizontal and vertical displacement of the wire, and the combination of the two can restrain the torsional displacement of the wire, so the combination of the two can suppress multi-order galloping, thus preventing galloping Effect.

The following specific experiments are used to verify the comprehensive anti-dance method combining the limit type anti-dance device and the phase-to-ground spacer according to the present invention. The technical scheme of the present invention is implemented on a transmission line for field verification. The experimental circuit is shown in Figure 1. The line span is 536 meters, there is no height difference, and the wind attack angle is 90°. In Figure 1, 1 is a wire, and 2 is an insulator String, 3 is the ground anchor, 4 is the limit type anti-dance device, and 5 is the phase-to-ground spacer. According to the method provided by the present invention, the phase-to-ground spacers are installed at 1/3 and 2/3 of the distance, and the pull angle of the phase-to-ground spacers is 52°. The same wind excitation is used to simulate the galloping of the wire, and the displacement response and tension change of the galloping before and after installing the anti-dancing device are obtained, as shown in Figure 2-5. Figure 2 is the vertical displacement of the midpoint of the span when the anti-dancing device is not installed, and Figure 3 For the vertical displacement of the midpoint of the span after the limit-type anti-dancing device is combined with the phase-to-ground spacer, it can be seen that the vertical displacement of the mid-point of the span is greatly reduced after the limit-type anti-dance device is combined with the phase-to-ground spacer. Small, the vertical displacement is reduced by about 89.7%, and the peak-to-peak value of the vertical displacement is reduced by about 90.8%; Figure 4 shows the tension change of the wire when the anti-dancing device is not installed, and Figure 5 shows the limit type anti-dancing device and the phase-to-ground interval The tension change of the wire after the rod is combined, it can be seen that the tension of the galloping wire is reduced by about 40% and the peak-to-peak tension is reduced by 79.6% after installing the limit-type anti-dancing device and the phase-to-ground spacer. It can be proved that the galloping is effectively suppressed under the anti-dancing scheme of the present invention by comparing the galloping amplitude and the wire tension.

The above embodiments are used to understand the method and core idea of the present invention. For those skilled in the art, any possible changes or substitutions without departing from the concept of the present invention belong to the protection scope of the present invention.

Claims (9)

1. A comprehensive anti-galloping method combining a limiting anti-galloping device and a phase-to-ground spacer is characterized by comprising the following steps:

step 1, determining the number of ground spacers and hanging point positions according to the span of a power transmission line;

when the span of the transmission line is less than or equal to 300 meters, two groups of phase-ground spacing rods need to be arranged; when the span of the power transmission line is more than 300 meters and less than or equal to 600 meters, three groups of phase-ground spacing rods are arranged; when the span is larger than 600 meters and smaller than 800 meters, four groups of phase-to-ground spacing rods are arranged;

step 2, looking up the main wind direction of the area where the power transmission line is located, and adopting different installation measures and installation angles for the phase-to-phase spacers according to the main wind direction data;

step 3, determining the number and the installation positions of the limiting anti-galloping devices according to the span of the power transmission line;

corresponding to different spans of the power transmission line, the number of groups of the limiting anti-galloping devices to be arranged is equal to the number of groups of phase-to-ground spacers correspondingly arranged to the spans minus 1, the phase-to-ground spacers and the limiting anti-galloping devices are arranged at intervals, and the limiting anti-galloping devices are vertically arranged below the wires;

step 4, fixing a limiting anti-galloping device, installing an acceleration sensor for sensing conductor galloping speed in the limiting anti-galloping device, and adjusting the length of a pull wire of the limiting anti-galloping device to enable the pull wire to be in a loose state; the length of the stay wire of the phase-to-phase spacer is adjusted to apply the pre-tightening force of 3KN to 5 KN.

2. The integrated anti-galloping method combining the limit type anti-galloping device and the phase-to-ground spacer according to claim 1, wherein:

in step 1, each group of phase-to-ground spacers comprises three phase-to-ground spacers, each phase-to-ground spacer is hung between a corresponding phase line and a ground anchor, and hanging points of each group of phase-to-ground spacers in the horizontal direction of the power transmission line are the same in position.

3. The integrated anti-galloping method combining the limit type anti-galloping device and the phase-to-ground spacer according to claim 2, wherein:

in step 1, when the span of the power transmission line is less than or equal to 300 meters, hanging point positions of each group of phase-to-ground spacers in the horizontal direction of the power transmission line are arranged at 1/3 and 2/3 of the span of the power transmission line;

when the span of the power transmission line is more than 300 meters and less than or equal to 600 meters, hanging points of each group of phase-to-ground spacers in the horizontal direction of the power transmission line are positioned at 2/9, 1/2 and 7/9 of the span of the power transmission line;

and when the span is larger than 600 meters and smaller than 800 meters, the hanging point position of each group of phase-to-ground spacers in the horizontal direction of the transmission line is at 1/9, 1/3, 2/3 and 8/9 of the span of the transmission line.

4. The integrated anti-galloping method combining the limit type anti-galloping device and the phase-to-ground spacer according to claim 3, wherein:

in step 2, according to the main wind direction of the area where the power transmission line is located, the installation measure of the phase spacers is determined to be the installation in the upwind direction, and the installation angle, namely the included angle formed by the stay wires of the phase spacers and the ground, is determined to be an acute angle, wherein the main wind direction is the wind direction of the power transmission line in the area in the season where the power transmission line is easy to swing.

5. The integrated anti-galloping method combining the limit type anti-galloping device and the phase-to-ground spacer according to claim 4, wherein:

the installation angle is between 40 and 80 degrees.

6. The integrated anti-galloping method combining the spacing type anti-galloping device and the phase-to-ground spacer according to claim 3 or 4, wherein:

in step 3, each group of the limiting anti-galloping devices comprises three limiting anti-galloping devices, namely: when the span of the power transmission line is less than or equal to 300 meters, a group of limiting anti-galloping devices are required to be arranged; when the span is more than 300 meters and less than or equal to 600 meters, two groups of limiting anti-galloping devices are required to be arranged; when the span is greater than 600 meters and less than or equal to 800 meters, three groups of limiting anti-galloping devices need to be arranged.

7. The integrated anti-galloping method combining the limit type anti-galloping device and the phase-to-ground spacer according to claim 6, wherein:

spacing formula anti-galloping device and looks ground conductor spacer interval setting on every looks wire, and each spacing formula anti-galloping device is installed between this wire adjacent two looks ground conductor spacers promptly.

8. The integrated anti-galloping method combining the spacing type anti-galloping device and the phase-to-ground spacer according to claim 3 or 7, wherein:

when the span of the power transmission line is less than or equal to 300 meters, selecting the middle point of the span of each phase of wire to vertically install a group of limiting anti-galloping devices; when the span of the power transmission line is more than 300 meters and less than or equal to 600 meters, two groups of limiting anti-galloping devices are installed at 1/3 and 2/3 of the span of each phase of lead; when the span is larger than 600 meters and smaller than or equal to 800 meters, three groups of limiting type anti-galloping devices are installed at 2/9, 1/2 and 7/9 of the span of each phase of lead.

9. A comprehensive anti-galloping method combining a spacing anti-galloping device and a ground spacer according to any one of claims 1 to 4 or 7, wherein:

when the acceleration sensor in the limiting anti-galloping device senses that the acceleration of the upward movement of the lead exceeds a set threshold value, the limiting anti-galloping device automatically applies pre-tightening force of 3-5 KN.

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