CN113541035B - Accurate ice melting system for ground wires and optical cables - Google Patents
Accurate ice melting system for ground wires and optical cables Download PDFInfo
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- CN113541035B CN113541035B CN202110585196.5A CN202110585196A CN113541035B CN 113541035 B CN113541035 B CN 113541035B CN 202110585196 A CN202110585196 A CN 202110585196A CN 113541035 B CN113541035 B CN 113541035B
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- optical cable
- deicing
- ice melting
- opgw
- tower
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
- H02G1/00—Methods or apparatus specially adapted for installing, maintaining, repairing or dismantling electric cables or lines
- H02G1/02—Methods or apparatus specially adapted for installing, maintaining, repairing or dismantling electric cables or lines for overhead lines or cables
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
- H02G7/00—Overhead installations of electric lines or cables
- H02G7/16—Devices for removing snow or ice from lines or cables
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- Suspension Of Electric Lines Or Cables (AREA)
- Communication Cables (AREA)
Abstract
The invention discloses a precise ice melting system aiming at a ground wire and an optical cable, wherein a transmission line is erected in a double-loop manner by adopting a same tower, an ice melting loop is constructed by adopting two modes of single-loop power failure ice melting and double-loop power failure ice melting, and an insulation structure is arranged between an OPGW optical cable and a transmission line tower; the single-circuit power failure deicing adopts a unilateral optical cable deicing wiring mode, and a fixed deicing device, a phase conductor on a power transmission line, an OPGW optical cable and a phase conductor in the power transmission line are connected to form a direct-current deicing through-flow loop; the double-circuit power failure deicing adopts a mode of simultaneously deicing by using a bilateral optical cable, and a fixed deicing device, a phase conductor on one side of a power transmission line, a side OPGW optical cable and a phase conductor on the opposite side of the power transmission line are connected to form a direct-current deicing current loop. The invention realizes direct-current deicing, avoids power grid loss caused by icing of the OPGW optical cable, effectively improves the capability of the line to cope with extreme weather such as rain, snow, ice and the like, and improves the running reliability of the line.
Description
Technical Field
The invention belongs to the technical field of power transmission engineering, and particularly relates to an icing and deicing technology of a power transmission line.
Background
Because of the landform characteristics of 'Qishan-water-one-field', a large number of mountain high-altitude power transmission lines exist in the Taizhou area. Meanwhile, the coastal area of southeast in Taizhou and the cold and humid area in winter create favorable conditions for the generation of ice coating on the line. Icing of a power transmission line can cause serious damage to the power transmission line, and mainly comprises the following steps:
1. the line icing can lead to the rapid increase of vertical load, so that the tower and hardware are overwhelmed to cause serious accidents such as tower falling, line breakage and the like;
2. the line ice coating can increase sag, and slight waving can easily cause interphase short circuit and tripping;
3. uneven icing or different-period deicing can lead to wire galloping under the action of specific wind force, a light person generates flashover and trips, a heavy person causes hardware fittings and cross arms to deform, and a pole tower falls down and breaks wires.
Therefore, the research and discussion of the ice melting technology have extremely important significance for solving the ice coating problem of the power transmission line in the high-humidity and high-altitude area.
At present, the commonly adopted deicing mode is to short-circuit three-phase wires by using an off-line circuit, and apply direct current to the circuit by using fixed or movable deicing devices at two ends of the circuit to form a loop, so that the circuit generates heat and melts ice. The ice melting effect of the mode on the lead is still good, and the ice melting of the mode on the ground wire or the optical cable is difficult to realize, and the reasons are as follows:
1. the ground wire or the optical cable is not insulated from the tower entirely, and the direct current applied to the two ends of the line cannot form a loop, so that the direct current cannot be applied to heat and melt ice.
2. The ground wire or the optical cable has much poorer conductive performance than the lead wire, larger loss caused in the ice melting process and unsatisfactory ice melting effect.
3. The optical fibers in the optical cable are sensitive to temperature, the heating temperature cannot be accurately controlled in the ice melting process, and the optical fibers are easily damaged when the heating temperature is too high, so that the optical path is interrupted.
In practical researches, the ground wires and the optical cables are easier to be covered with ice and have broken wires under the weather of rain, snow and ice due to the characteristics of smaller wire diameter and no through flow in a normal state. Therefore, how to develop a precise ice melting technology for the ground wire and the optical cable is a great difficulty which is plagued by numerous power practitioners at present.
Disclosure of Invention
Aiming at the defects of the prior art, the technical problem to be solved by the invention is to provide the accurate ice melting system aiming at the ground wire and the optical cable, so that the ice coating and the broken wire accidents in the rainy, snowy and frozen weather are avoided.
In order to solve the technical problems, the invention adopts the following technical scheme: an accurate ice melting system aiming at a ground wire and an optical cable is characterized in that a power transmission line is erected in a same tower in a double-loop manner, an ice melting loop is constructed in a single-loop power failure ice melting mode and a double-loop power failure ice melting mode, and an insulating structure is arranged between an OPGW optical cable and a power transmission line tower;
the single-circuit power failure deicing adopts a unilateral optical cable deicing wiring mode, and a fixed deicing device, a phase conductor on a power transmission line, an OPGW optical cable and a phase conductor in the power transmission line are connected to form a direct-current deicing through-flow loop;
the double-circuit power failure deicing adopts a mode of simultaneously deicing by using a bilateral optical cable, and a fixed deicing device, a phase conductor on one side of a power transmission line, a side OPGW optical cable and a phase conductor on the opposite side of the power transmission line are connected to form a direct-current deicing current loop. Preferably, for the tangent tower, an OPGW optical cable is fixed by adopting a suspension insulator string, the ground wires of the OPGW optical cable are grounded base by base, and a ground wire discharge gap is arranged.
Preferably, for the strain tower, the tail end of the OPGW is insulated from the tower body of the tower through a strain insulator string, and a ground wire discharge gap is arranged on the ground wire of the OPGW optical cable.
Preferably, the tension tower is adopted at the optical cable segmentation position, and the whole line of the down-conducting part of the OPGW optical cable is led down from the outside of the tower body by adopting a post insulator and the tower body to keep a safe distance.
Preferably, the two sections of OPGW optical cables are connected through an optical cable splice box, the optical cable splice box adopts an OPGW isolation type insulation splice box to achieve the purpose of photoelectric separation of the optical cables, and the residual optical cables are fixed on a post insulator and kept insulated with a tower body of the tower.
According to the technical scheme, the OPGW optical cable ice melting adopts a direct-current ice melting mode, the fixed ice melting device is used as direct-current output, and the lead and the OPGW optical cable are connected in series to form a through-current loop, so that the direct-current ice melting function is realized, the power grid loss caused by ice coating of the OPGW optical cable is avoided, the capacity of a circuit for coping with extreme weather such as rain, snow and ice is effectively improved, and the running reliability of the circuit is improved.
The specific technical scheme and the beneficial effects of the invention are described in detail in the following detailed description with reference to the accompanying drawings.
Drawings
The invention is further described with reference to the drawings and detailed description which follow:
FIG. 1 is a schematic diagram of a single-pass OPGW cable ice melting circuit;
FIG. 2 is a schematic diagram of a dual-loop OPGW cable ice melting circuit;
fig. 3 is a schematic diagram of an OPGW isolation closure.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. The following description of at least one exemplary embodiment is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In order to avoid the power grid loss caused by the icing of the OPGW optical cable, effectively improve the capability of the line to cope with extreme weather such as rain, snow, ice and the like, improve the running reliability of the line, the direct-current ice melting loop is formed by connecting the lead and the OPGW optical cable in series by fixing the ice melting device as a power source point, the OPGW optical cable of the power transmission line is subjected to insulation transformation, and the OPGW optical cable has the capability of direct-current ice melting by depending on a digital icing whole-process monitoring system, a precise ice melting system and the like.
The specific embodiment of the invention provides a real-time monitoring OPGW optical cable direct current ice melting system, a power transmission line is erected in a same tower in a double-loop mode, and an ice melting loop is constructed in a single-loop power failure ice melting mode and a double-loop power failure ice melting mode. Insulation transformation is performed on an OPGW optical cable of the power transmission line, and an insulation structure is formed between the OPGW optical cable and a tower of the power transmission line. Therefore, the invention constructs a precise ice melting system aiming at the ground wire and the optical cable, and constructs a digital icing and ice melting whole process monitoring system aiming at icing and ice melting process monitoring.
The precise ice melting system for the ground wire and the optical cable adopts two modes of single-circuit power failure ice melting and double-circuit power failure ice melting to construct an ice melting loop.
Referring to fig. 1, single-circuit power failure ice melting adopts a single-side optical cable ice melting wiring mode, and is provided with a fixed ice melting device 1, a down-draw device 2, a tower cable 3, a tower one 4, a tower two 5, a wire and an OPGW optical cable. The fixed ice melting device 1, the phase conductor on the power transmission line, the OPGW optical cable and the phase conductor in the power transmission line are connected to form a direct-current ice melting through-flow loop.
Referring to fig. 2, the double-circuit power failure ice melting adopts a double-side optical cable simultaneous ice melting wiring mode, and is provided with a fixed ice melting device 1, a down-drawing device 2, a tower cable 3, a tower one 4, a tower two 5, a wire and a ground wire. The fixed ice melting device, the phase conductor on one side of the power transmission line, the one-side OPGW optical cable, the opposite-side OPGW optical cable and the phase conductor on the opposite side of the power transmission line are connected to form a direct-current ice melting through-flow loop.
At present, the OPGW optical cable generally adopts a base-by-base grounding mode, and the OPGW optical cable needs to be subjected to full-line insulation transformation in order to realize ice melting, so that the OPGW optical cable has the capability of being connected with direct current to form a loop. Therefore, insulation configuration is needed to be reasonably carried out according to the deicing voltage and the induced voltage, and the insulation level and the insulation gap of the ground wire are selected, so that the modified ground wire meets the induced voltage limit value and the lightning protection requirement under the daily operation working condition and meets the insulation strength requirement under the deicing working condition.
The OPGW ground wire insulation transformation design mainly comprises transformation of a full-section OPGW optical cable fitting and transformation of an OPGW optical cable downlead of a first section tower and a last section tower, and the ground wire in the ice melting process can form an electrified loop through the insulation transformation of the OPGW optical cable, so that the insulation requirement and the lightning protection requirement of the tower are met.
For the tangent tower, the OPGW ground wire adopts a base-by-base grounding mode, an existing suspension wire clamp is modified into a suspension insulator string, 1 insulator sheet is selected according to the maximum output voltage of 9.5kV, the existing ground wire is removed, and a ground wire discharge gap is arranged.
For the strain tower, the OPGW ground wire on the strain tower achieves the purpose of insulation transformation by additionally installing the strain insulator string on the large side and the small side. In order to keep the length of the ground wire in the span unchanged, the length of the OPGW ground wire is retracted for a certain distance during transformation, a connecting fitting of the original OPGW and the tower body is removed, a strain insulator string is additionally arranged between the tail end of the OPGW and the tower body, 1 insulator sheet is selected, the original ground wire is removed, and a ground wire discharge gap is arranged. The OPGW is fixed on the ground wire bracket by a preformed armor rod.
The tower head part at the segment is consistent with the tension tower, the insulation mode of the down-leading part and the tower body needs to be considered, and the whole line of the down-leading part of the optical cable is considered to be led down from the outside of the tower body by adopting a post insulator and the tower body to keep a safe distance.
As shown in fig. 3, the two OPGW optical cables are connected by an optical cable closure 6. In order to realize insulation of the optical cable splice closure, the optical cable splice closure adopts an OPGW isolation type insulation splice closure to achieve the purpose of photoelectric separation of the optical cable, a hollow composite insulator 61 is arranged between the optical cable splice closure 6 and the OPGW optical cable, the optical cable splice closure 6 is fixed on a post composite insulator 62, and meanwhile, the residual optical cable is fixed on the post composite insulator and keeps insulation with a tower body of a tower.
The digital icing and deicing whole process monitoring system comprises:
microclimate on-line monitoring device: the micro-meteorological online monitoring device is used for monitoring the meteorological environment of the place where the line is located and transmitting the acquired meteorological environment parameters to the monitoring host in real time through a network;
on-line monitoring device for temperature measurement of ground wire: the wire and ground wire temperature measurement on-line monitoring is used for sensing and automatically collecting the surface temperature of the wire and OPGW optical cable, and transmitting the collected temperature parameters to a monitoring host in real time through a network;
icing on-line monitoring device: the icing on-line monitoring device is used for monitoring the icing condition of the power transmission line and transmitting the icing condition of the power transmission line to the monitoring host in real time through a network;
mist penetrating type video on-line monitoring device: the fog penetrating type video on-line monitoring device is used for shooting and returning the ice coating state of the wire and the OPGW optical cable and the actual ice melting and ice removing process of the wire and the OPGW optical cable, and transmitting the video to the monitoring host in real time through a network;
monitoring a host: the monitoring host is in communication connection with the microclimate online monitoring device, the ground wire temperature measurement online monitoring device, the icing online monitoring device and the fog penetrating type video online monitoring device.
Specifically, the meteorological environment parameters comprise temperature, humidity, wind direction, wind speed and air pressure parameters, the collected various meteorological parameters and the change conditions thereof are transmitted to a system host in real time through a network, and the collected meteorological environment parameters are stored, counted and analyzed by a monitoring host.
In order to monitor the icing condition of the optical cable in the daily operation process and the deicing condition in the deicing process in real time, the icing tension sensor can be arranged at the hanging point of the suspension insulator string of the tangent tower at the higher altitude. The ice coating on-line monitoring device comprises an ice coating tension sensor, wherein the ice coating tension sensor is additionally arranged on a line suspension string, and if the tension value monitored by the ice coating tension sensor is higher than a set normal value, ice melting operation is required to be continued.
In order to monitor the icing condition of the optical cable in the daily operation process and the deicing condition of the optical cable in the deicing process in real time, a fog penetrating type video on-line monitoring device is arranged on a linear tower head lead (ground wire) at a position with a higher altitude of a two-circuit line.
In order to avoid the influence of direct current ice melting on the performance of the optical cable, the temperature of the OPGW optical cable in the ice melting process must be strictly controlled. The ice melting section optical cable can be divided into an ice coating section on the tower, a tower body section and a drainage wire lap joint point, and the highest temperature in the ice melting process is located at the drainage wire lap joint point. A temperature monitoring device is arranged at the joint of the drainage line on the tower and the optical cable so as to strictly control the temperature rise of the optical cable; meanwhile, a temperature monitoring device is arranged at the outlet point of the tower head optical cable for monitoring the temperature rise and ice melting effect of the optical cable in real time.
Furthermore, the temperature of the inner core of the OPGW optical cable is controlled to be within 65 ℃. The short-term limit temperature of the OPGW optical cable is not more than 80 ℃.
The temperature of the inner core of the optical cable is controlled by controlling the direct-current ice melting current. Taking the fixed ice melting device with the capacity of 67.2MW, the maximum output DC voltage of 13.3kV and the minimum output DC voltage of 1.5kV as an example, the range of the output DC ice melting current is adjustable by 9 grades according to the different lengths of the needed ice melting lines and the different sections of the wires. Under the two connection modes, the ice melting current values under each gear are shown in tables 1 and 2 respectively, and the minimum output current under the single-side ground wire ice melting connection mode can be seen to be 541A, and the maximum current is seen to be 4683A. Minimum output current 271A and maximum current 2342A in the double-side ground wire ice-melting wiring mode.
Table 1 Ice melting device ice melting current output under different gear (unilateral ground wire ice melting connection mode)
Table 2 deicing Current output of the deicing device in different gears (double-sided ground wire deicing connection mode)
Temperature rise characteristics of OPGW cable:
(1) In the through-flow state of the OPGW optical cable, the surface temperature rise of the optical cable is gradually different from that of the optical core due to the fact that the heat dissipation of the surface of the optical cable is faster, the optical core temperature is gradually higher than the surface temperature, and the optical core temperature in the final state is far higher than the surface temperature;
(2) After a certain time, the temperature of the surface and the inner core of the optical cable tends to be steady, and the steady temperature is positively related to the direct current.
According to the accurate ice melting system, the states of the temperature of the inner core of the optical cable, the surface temperature of the optical cable and the like are monitored in real time by means of the digital ice coating and melting whole process monitoring system, and ice melting current control is achieved by connecting current real-time regulating equipment in a direct current ice melting loop in series. By combining the temperature rise characteristic curve of the inner core of the optical cable and through intelligent linkage of the direct-current ice melting current value and the optical core temperature data, ice melting current and optical core temperature can be controlled and simultaneously controlled, and the optical cable safety is effectively protected.
While the invention has been described in terms of specific embodiments, it will be appreciated by those skilled in the art that the invention is not limited to the specific embodiments described above. Any modifications which do not depart from the functional and structural principles of the present invention are intended to be included within the scope of the appended claims.
Claims (4)
1. An accurate ice melting system to ground wire and optical cable adopts two ways of ice melting in single power failure and two ways of ice melting in double power failure to construct an ice melting loop, and is characterized in that: an insulating structure is arranged between the OPGW optical cable and the transmission line tower; the single-circuit power failure deicing adopts a unilateral optical cable deicing wiring mode, and a fixed deicing device, a phase conductor on a power transmission line, an OPGW optical cable and a phase conductor in the power transmission line are connected to form a direct-current deicing through-flow loop; the double-circuit power failure deicing adopts a mode of simultaneously deicing a bilateral optical cable and a wiring mode, a fixed deicing device, a phase conductor on one side of a power transmission line, an OPGW optical cable on one side, an OPGW optical cable on the opposite side of the power transmission line, and the phase conductor on the opposite side of the power transmission line are connected to form a direct-current deicing flow path, the two sections of OPGW optical cables are connected through an optical cable splice box, the optical cable splice box adopts an OPGW isolation type insulating splice box to achieve the purpose of photoelectric separation of the optical cable, a hollow composite insulator is arranged between the optical cable splice box and the OPGW optical cable, the optical cable splice box is fixed on a support composite insulator, the optical cable residual cable is fixed on the support insulator and keeps insulation with a tower body of a tower, the cable in the deicing section can be divided into an ice-over-tower section, a tower body section and a drainage wire lap joint, a temperature monitoring device is arranged on a drainage wire and an optical cable lap joint, and a temperature monitoring device is arranged on a tower head optical cable outlet point.
2. The precision ice melting system for ground wires and fiber optic cables of claim 1, wherein: for the tangent tower, an OPGW optical cable is fixed by adopting a suspension insulator string, the ground wires of the OPGW optical cable are grounded base by base, and a ground wire discharge gap is arranged.
3. The precision ice melting system for ground wires and fiber optic cables of claim 1, wherein: for the strain tower, the tail end of the OPGW is insulated from the tower body of the tower through a strain insulator string, and a ground wire of the OPGW optical cable is provided with a ground wire discharge gap.
4. The precision ice melting system for ground wires and fiber optic cables of claim 1, wherein: the cable section is provided with a tension tower, and the whole line of the down-leading part of the OPGW cable is led down from the outside of the tower body by adopting a post insulator and the tower body to keep a safe distance.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110585196.5A CN113541035B (en) | 2021-05-27 | 2021-05-27 | Accurate ice melting system for ground wires and optical cables |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110585196.5A CN113541035B (en) | 2021-05-27 | 2021-05-27 | Accurate ice melting system for ground wires and optical cables |
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| CN113541035B true CN113541035B (en) | 2023-08-15 |
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Citations (3)
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|---|---|---|---|---|
| CN102856869A (en) * | 2012-08-30 | 2013-01-02 | 中国电力工程顾问集团西南电力设计院 | Wiring method for realizing direct-current deicing of ground wire of converter station |
| CN103247992A (en) * | 2013-05-07 | 2013-08-14 | 陈广生 | DC deicing method for overhead ground wires and OPGWs in electric transmission lines |
| CN106159798A (en) * | 2016-08-23 | 2016-11-23 | 中国电力工程顾问集团西南电力设计院有限公司 | A kind of transmission line of electricity connection in series-parallel mixing ground wire de-icing method |
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2021
- 2021-05-27 CN CN202110585196.5A patent/CN113541035B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102856869A (en) * | 2012-08-30 | 2013-01-02 | 中国电力工程顾问集团西南电力设计院 | Wiring method for realizing direct-current deicing of ground wire of converter station |
| CN103247992A (en) * | 2013-05-07 | 2013-08-14 | 陈广生 | DC deicing method for overhead ground wires and OPGWs in electric transmission lines |
| CN106159798A (en) * | 2016-08-23 | 2016-11-23 | 中国电力工程顾问集团西南电力设计院有限公司 | A kind of transmission line of electricity connection in series-parallel mixing ground wire de-icing method |
Non-Patent Citations (1)
| Title |
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| 光纤复合架空地线直流融冰绝缘化改造方法应用研究;邓元实等;《四川电力技术》;20190630;第44-49页 * |
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