CN115296246B - High-voltage direct-current uninterrupted ground wire ice melting circuit, equipment and operation method - Google Patents
High-voltage direct-current uninterrupted ground wire ice melting circuit, equipment and operation method Download PDFInfo
- Publication number
- CN115296246B CN115296246B CN202211032258.0A CN202211032258A CN115296246B CN 115296246 B CN115296246 B CN 115296246B CN 202211032258 A CN202211032258 A CN 202211032258A CN 115296246 B CN115296246 B CN 115296246B
- Authority
- CN
- China
- Prior art keywords
- switch
- ice melting
- ice
- ground wire
- melting
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000002844 melting Methods 0.000 title claims abstract description 276
- 230000008018 melting Effects 0.000 title claims abstract description 249
- 238000000034 method Methods 0.000 title claims abstract description 17
- 230000005540 biological transmission Effects 0.000 claims description 28
- 239000004020 conductor Substances 0.000 claims description 7
- 239000012212 insulator Substances 0.000 claims description 7
- 238000002955 isolation Methods 0.000 claims 1
- 230000006698 induction Effects 0.000 description 6
- 238000010309 melting process Methods 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 4
- 230000008878 coupling Effects 0.000 description 3
- 238000010168 coupling process Methods 0.000 description 3
- 238000005859 coupling reaction Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000012423 maintenance Methods 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- WABPQHHGFIMREM-UHFFFAOYSA-N lead(0) Chemical compound [Pb] WABPQHHGFIMREM-UHFFFAOYSA-N 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 230000011218 segmentation Effects 0.000 description 2
- 230000033228 biological regulation Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000001808 coupling effect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 230000029087 digestion Effects 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000007667 floating Methods 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 230000009545 invasion Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000005404 monopole Effects 0.000 description 1
- 239000013307 optical fiber Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
Classifications
-
- 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
-
- 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
- H02G13/00—Installations of lightning conductors; Fastening thereof to supporting structure
- H02G13/40—Connection to earth
-
- 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
- H02G13/00—Installations of lightning conductors; Fastening thereof to supporting structure
- H02G13/80—Discharge by conduction or dissipation, e.g. rods, arresters, spark gaps
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
- H02H9/04—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
- H02H9/08—Limitation or suppression of earth fault currents, e.g. Petersen coil
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
The application relates to a high-voltage direct-current uninterrupted ground wire ice melting circuit, equipment and an operation method, wherein the high-voltage direct-current uninterrupted ground wire ice melting circuit comprises an ice melting power supply device, a first ice melting switch, a second ice melting switch and a connecting switch; the first end of the ice melting power supply device is connected with the first end of the first ice melting switch, the second end of the ice melting power supply device is connected with the first end of the second ice melting switch, the second end of the first ice melting switch is connected with the tower down-lead of the head end of the tower down-lead of the ordinary ground wire of the section to be melted, the second end of the second ice melting switch is connected with the tower down-lead of the head end of the tower down-lead of the OPGW ground wire of the section to be melted, the first end of the connecting switch is connected with the tail end of the ordinary ground wire, and the second end of the connecting switch is connected with the tail end of the OPGW ground wire of the section to be melted.
Description
Technical Field
The application relates to the field of direct current transmission, in particular to a high-voltage direct current uninterrupted ground wire ice melting circuit, equipment and an operation method.
Background
Currently, the hvdc transmission is generally provided with double ground wires, including a common ground wire and an OPGW ground wire (Optical Fiber Composite Overhead Ground Wire ). In the existing DC ground wire ice melting technology based on power failure, an ice melting power supply is arranged in a converter station, after DC power failure, the DC ice melting power supply is connected with the anode and the cathode of a DC lead through an ice melting pipe bus, and an ice melting section to be melted is connected to the anode and the cathode lead in a lap joint mode, so that ice melting can be realized.
However, this ground wire deicing technique needs to be performed in a power outage state. The direct current outage application only for deicing influences the power supply reliability, influences the power guarantee, the long-distance line deicing needs repeated and long-time power failure, the sending end faces the problems of wind abandoning, light abandoning and water abandoning, the power of the receiving end cannot be guaranteed, and the electric quantity loss is overlarge.
Disclosure of Invention
Based on the above, it is necessary to provide a high-voltage direct-current uninterrupted ground wire ice melting circuit, equipment and an operation method aiming at the problem of overlarge direct-current shutdown ice melting electric quantity loss.
A high-voltage direct-current uninterrupted ground wire ice melting circuit comprises: the ice melting power supply device, the first ice melting switch, the second ice melting switch and the connecting switch; the first end of the ice melting power supply device is connected with the first end of the first ice melting switch, the second end of the ice melting power supply device is connected with the first end of the second ice melting switch, the second end of the first ice melting switch is connected with the head end of the pole tower down wire of the common ground wire of the section to be melted, the second end of the second ice melting switch is connected with the head end of the pole tower down wire of the OPGW of the section to be melted, the first end of the connecting switch is connected with the tail end of the common ground wire, and the second end of the connecting switch is connected with the tail end of the OPGW ground wire;
The ice melting power supply device is used for providing current required by ice melting of the common ground wire and the OPGW ground wire; the common ground wire and the OPGW ground wire are conducted when the connecting switch is closed, so that an ice melting loop is formed; when the first ice melting switch and the second ice melting switch are closed, the current output by the ice melting power supply device flows through the ice melting loop to melt ice.
In one embodiment, the high-voltage direct-current uninterrupted ground wire ice melting circuit further comprises a first grounding device and a second grounding device, wherein a first end of the first grounding device is connected with a first end of the ice melting power supply device, and a second end of the first grounding device is grounded; the first end of the second grounding device is connected with the second end of the ice melting power supply device, and the second end of the second grounding device is grounded.
In one embodiment, the first grounding device and the second grounding device are resistors with resistance values of 5k omega-20 k omega.
In one embodiment, the high-voltage direct-current uninterrupted ground wire ice melting circuit further comprises a first lightning arrester and a second lightning arrester, wherein the first end of the first lightning arrester is connected with the first end of the ice melting power supply device, and the second end of the first lightning arrester is grounded; the first end of the second lightning arrester is connected with the second end of the ice melting power supply device, and the second end of the second lightning arrester is grounded.
In one embodiment, the high-voltage direct-current uninterrupted ground wire ice melting circuit further comprises a first grounding gap device and a second grounding gap device, wherein a first end of the first grounding gap device is connected with the head end of a common ground wire tower down wire of a section to be melted, and a second end of the first grounding gap device is grounded; the first end of the second grounding gap device is connected with the head end of the down wire of the OPGW ground wire tower of the section to be melted, and the second end of the second grounding gap device is grounded.
In one embodiment, the first and second ground gap devices are each ground insulator parallel gaps.
In one embodiment, the high-voltage direct-current uninterrupted ground wire ice melting circuit further comprises a first grounding switch and a second grounding switch, wherein a first end of the first grounding switch is connected with the tail end of a common ground wire, and a second end of the first grounding switch is grounded; and a first end of the second grounding switch is connected with the tail end of the OPGW ground wire, and a second end of the second grounding switch is grounded.
In one embodiment, the first ice melting switch, the second ice melting switch and the connecting switch are all isolating switches, and the first grounding switch and the second grounding switch are all grounding disconnecting switches.
The high-voltage direct-current uninterrupted ground wire ice melting operation method is realized based on the high-voltage direct-current uninterrupted ground wire ice melting equipment and comprises the following steps of:
the first grounding switch and the second grounding switch are in a closing state when ice is not melted, and the connecting switch, the first ice melting switch and the second ice melting switch are in a separating state;
The method comprises the following steps of continuously operating the high-voltage direct-current power transmission during ice melting, connecting a switch in the first step, connecting a first ice melting switch and a second ice melting switch in the second step, connecting a first grounding switch and a second grounding switch in the third step, and unlocking an ice melting device in the fourth step to start ice melting.
The high-voltage direct-current uninterrupted ground wire ice melting circuit, equipment and an operation method. The ice melting power supply device is used for providing current required by ice melting of the common ground wire and the OPGW ground wire of the section to be ice-melted; when the connecting switch is closed, the common ground wire is conducted with the OPGW ground wire of the section to be iced to form an ice melting loop; when the first ice melting switch and the second ice melting switch are closed, the current output by the ice melting power supply device flows through the ice melting loop to melt ice. The common ground wire and the OPGW wire are connected in series and then directly connected to the ice melting power supply, so that the direct current can maintain normal operation, and the problem of overlarge ice melting electric quantity loss in a power failure state is effectively solved.
Drawings
FIG. 1 is a schematic diagram of a conventional DC power-off ground wire series ice melting circuit;
FIG. 2 is a schematic diagram of a conventional DC power-off ground wire parallel ice melting circuit;
FIG. 3 is a schematic diagram of an embodiment of uninterrupted ground wire ice melting.
Detailed Description
The present application will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present application more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.
It will be understood that the terms first, second, etc. as used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another element. For example, a first resistance may be referred to as a second resistance, and similarly, a second resistance may be referred to as a first resistance, without departing from the scope of the application. Both the first resistor and the second resistor are resistors, but they are not the same resistor.
In the following embodiments, "connected", and the like are understood to mean "electrically connected", "communicatively connected", and the like, if the connected circuits, modules, units, and the like have electrical signals or data transferred therebetween.
As shown in fig. 1, one embodiment of current ground wire ice melting employs such a dc power down ground wire series ice melting circuit. The common method for carrying out ice melting treatment on the common ground wire and the OPGW ground wire is as follows: the ice melting power supply is arranged in the converter station, and after the direct current is stopped, the ice melting power supply is connected with the anode and the cathode of the direct current lead through the ice melting pipe bus. The common ground wire and the OPGW ground wire are connected in series and then are lapped on the positive electrode and the negative electrode of the direct current lead, so that ice melting can be realized. Further, the connection mode of the common ground wire and the OPGW ground wire is not unique, and as shown in fig. 2, the common ground wire and the OPGW ground wire may be lapped on the positive electrode and the negative electrode of the dc lead by a parallel connection mode to implement ice melting.
Based on the above analysis, when the ice melting process is performed on the ground wire icing area, the power failure process is performed on the dc wire, and the ice melting method has a plurality of problems:
1. the remote direct current transmission has more ice melting sections, low ice melting efficiency and complex wiring.
According to relevant regulations, an important power transmission line with the thickness of 110kV and above and 10mm is designed to be provided with an ice melting means, and according to the requirement of a 10mm ice area, long-distance whole line long distance can be required to be provided with the ice melting means for long-distance direct current power transmission. When ice is melted, the ground wire is in an insulating state, if the ice melting voltage is too high, the insulating cost is greatly increased, so that the ice melting voltage cannot be too high, the ice melting segmentation length is smaller, 50-100 km is generally considered, and for a long-distance direct current transmission line with the power consumption of more than 2000 km, segmentation multiple wiring is complex. Each time of ice melting is designed according to one hour, the actual situation is about 30-90 minutes, but the preparation time and the re-electricity time are as long as three-four hours, and the ice melting requirement time of each section is too long. When a long-distance direct current transmission line is met, the sections are more and the wiring is complex, meanwhile, the ice melting requirement time of each section is too long, the ice melting efficiency is low, and the operation and maintenance are very inconvenient.
2. The large-capacity ice melting device is required to be configured in the station, and the occupied area and the operation and maintenance difficulty are increased.
The large-capacity ice melting device and ice melting pipe nut are required to be configured in the general station, the occupied area and the operation and maintenance workload are increased, links such as land-saving evaluation and the like are required to be added for early-stage work for the converter station, and the occupied area is particularly unfriendly for the load center area with the land-down size and the gold.
3. The direct current stops running and the ice melting electric quantity is lost greatly.
At present, a large-scale power supply base end-sending net rack is generally weak, and power cannot be sent out through other channels after direct current is stopped. Application of direct current shutdown for ice melting only affects power supply reliability, and may cause wind and water discarding and light discarding, affecting power guarantee. Taking the ultra-high voltage direct current engineering of the great bay area of the southeast power transmission which is incorporated into the power development planning as an example, the power transmission end comprises large-scale new energy and water and has no digestion capability, if the direct current is stopped because of the ice melting of the local ground wire, the long-distance line needs to be powered off for a plurality of times for a long time, and the power transmission end has the problems of light discarding and water discarding; and the power of the receiving end large bay area cannot be ensured. The method comprises the steps of calculating according to direct current of +/-800 kilovolts and 1000 kilowatts, calculating according to 50-100 km of each ice melting section, dividing a full line 2000 km ice melting section into 20-40 ice melting sections, and melting ice for more than 4 hours (including preparation time and re-electricity time) each time, wherein electric quantity loss of 4000 kilowatts is caused, calculating according to electricity price of 0.453 yuan per kilowatt hour in Guangdong, and if all the electric quantity is discarded, the electric quantity loss is close to 2000 kiloyuan each time; if only the power transmission cost is calculated, the power transmission loss is up to about 400-600 ten thousand yuan. When icing occurs during peak load periods, the receiving end may also face tens of millions of load losses. All hydropower and new energy sources in the southeast of the Tibetan are sent out from direct current, cannot be transferred through other lines, are difficult to melt ice in a power failure, and can cause a large amount of water and light abandoning.
Therefore, research on new ice melting technology is needed to break the existing dilemma of power outage ice melting technology.
Based on this, in one embodiment, as shown in fig. 3, there is provided a high voltage direct current uninterrupted ground wire ice melting circuit including an ice melting power supply device 110, a first ice melting switch 141, a second ice melting switch 142, and a connection switch 170. The first end of the ice melting power supply device 110 is connected with the first end of the first ice melting switch 141, the second end of the ice melting power supply device 110 is connected with the first end of the second ice melting switch 142, the second end of the first ice melting switch 141 is connected with the head end of the pole tower down wire of the ordinary ground wire of the section to be melted, the second end of the second ice melting switch 142 is connected with the head end of the pole tower down wire of the OPGW of the section to be melted, the first end of the connecting switch 170 is connected with the tail end of the ordinary ground wire, and the second end of the connecting switch 170 is connected with the tail end of the OPGW ground wire of the section to be melted; the ice melting power supply device 110 is used for providing current required by ice melting of the common ground wire and the OPGW ground wire; the connection switch 170 conducts the common ground wire and the OPGW ground wire when being closed to form an ice melting loop; when the first ice-melting switch 141 and the second ice-melting switch 142 are closed, the current output from the ice-melting power supply device 110 flows through the ice-melting circuit to melt ice.
The specific types of the first end and the second end of the ice melting power supply device 110 are not unique, for example, the first end of the ice melting power supply device 110 may be a power positive interface, and the second end of the ice melting power supply device 110 is a power negative interface; meanwhile, the first end of the ice melting power supply device 110 may be a power supply negative electrode interface, and the second end of the ice melting power supply device 110 may be a power supply positive electrode interface. In this embodiment, the first end of the ice melting power supply device 110 is a power supply positive electrode interface, and the second end of the ice melting power supply device 110 is a power supply negative electrode interface.
Further, the first ends of the first ice-melting switch 141, the second ice-melting switch 142 and the connection switch 170 are input ends, and the second ends of the first ice-melting switch 141, the second ice-melting switch 142 and the connection switch 170 are output ends. Specifically, the positive terminal of the ice melting power supply device 110 is connected to the input terminal of the first ice melting switch 141, the negative terminal of the ice melting power supply device 110 is connected to the input terminal of the second ice melting switch 142, the output terminal of the first ice melting switch 141 is connected to the head terminal of the pole tower down-lead of the common ground wire, the output terminal of the second ice melting switch 142 is connected to the head terminal of the pole tower down-lead of the OPGW ground wire, the input terminal of the connection switch 170 is connected to the tail terminal of the common ground wire, and the output terminal of the connection switch 170 is connected to the tail terminal of the OPGW ground wire.
It should be understood that the specific arrangement of the ice melting power supply device 110 is not limited, and for example, a small ice melting workstation may be arranged in the ice melting key region, and the ice melting power supply device 110 may be configured in the ice melting workstation to supply the electric energy required for melting ice. The ice melting power supply 110 may be a mobile ice melting device, and may supply electric energy by a diesel generator or the like.
It will be appreciated that if the ice melting line is longer, the ice melting power supply 110 is powered more during operation, and the ice melting power supply should not consider moving the ice melting device, and the risk is easily caused by too high resistance of the ground network due to too high induced voltage. Therefore, in this embodiment, it is preferable to provide an ice melting workstation in the ice melting key region, and a symmetric bipolar soft dc converter valve based on an IGBT (Insulated Gate Bipolar Transistor ) or a conventional dc converter valve based on a thyristor is provided in the ice melting workstation as the ice melting power supply device 110. By arranging the ice melting workstation, the grounding grid is paved according to the 35kV transformer substation standard, the resistance of the grounding grid is reduced, and the risk of damaging human bodies and equipment by induced voltage in the ice melting process is reduced.
Further, the specific structures of the first ice-melting switch 141, the second ice-melting switch 142 and the connection switch 170 are not unique, for example, the first ice-melting switch 141, the second ice-melting switch 142 and the connection switch 170 may be controlled by a knife switch, a ship switch or the like, or may be controlled by a switching device. In this embodiment, the first ice melting switch 141, the second ice melting switch 142 and the connection switch 170 are all knife switch.
The high-voltage direct-current uninterrupted ground wire ice melting circuit is used for providing current required by ice melting of a common ground wire and an OPGW ground wire by the ice melting power supply device 110; when the connecting switch 170 is closed, the common ground wire and the OPGW ground wire of the section to be iced are conducted to form an ice melting loop; when the first ice-melting switch 141 and the second ice-melting switch 142 are closed, the current output from the ice-melting power supply device 110 flows through the ice-melting circuit to melt ice. The common ground wire and the OPGW wire are connected in series and then are directly connected to the ice melting power supply 110, the grounding device is adopted to reduce the induction voltage, the insulator is adopted to protect the ice melting device from lightning strike (the possibility is small, the ice period is generally lightning-free), the induction voltage is too high (the bipolar operation is not provided with the induction voltage, the unipolar operation induction voltage is restrained at a receivable value through the grounding resistor), the ground wire is flashover (the ice coating jump is possibly caused, the ice melting starting value is reduced), and the like.
In one embodiment, as shown in fig. 3, the ice melting circuit further includes a first grounding device 121 and a second grounding device 122, a first end of the first grounding device 121 is connected to a first end of the ice melting power supply device 110, and a second end of the first grounding device 121 is grounded; the first end of the second grounding device 122 is connected to the second end of the ice melting power supply device 110, and the second end of the second grounding device 122 is grounded.
The first ends of the first grounding device 121 and the second grounding device 122 are input ends, and the second ends of the first grounding device 121 and the second grounding device 122 are output ends. Specifically, the input end of the first grounding device 121 is connected to the positive end of the ice melting power supply device 110, and the output end of the first grounding device 121 is grounded; the input end of the second grounding device 122 is connected to the negative end of the ice melting power supply device 110, and the output end of the second grounding device 122 is grounded.
It will be appreciated that the specific structures of the first grounding device 121 and the second grounding device 122 are not unique, for example, a resistor box or a varistor may be used as the first grounding device 121 and the second grounding device 122 to access the ice melting circuit, and a resistor with a high resistance value may also be directly used as the first grounding device 121 and the second grounding device 122 to access the ice melting circuit.
In one embodiment, the first and second ground devices 121 and 122 are each resistances of 5kΩ -20kΩ resistance. The risk of damage to personal equipment caused by overlarge induced voltage can exist in the uninterrupted ice melting process, and the induced voltage exists in an ice melting loop after the ground wire is indirectly grounded. The first and second ground resistor devices 121 and 122 can suppress an induced overvoltage by high-resistance grounding, and ensure the safety of the ice melting circuit.
Specifically, the direct current line induced voltage is mainly electrostatic coupling and ion flow field induced voltage. The direct current transmission voltage and current are basically unchanged, no electromagnetic coupling effect exists between the conductive wires, but any two of the conductive wires are mutually influenced by an electric field, namely, electrostatic coupling is realized. In the case of a floating conductor or a grounded conductor via a large resistor in the vicinity of a dc transmission line, space charges moving onto such objects cannot flow directly into the ground in the dc ion flow field, which makes the objects generate an induced voltage that can be as high as several thousand volts. As shown in table 1, under the conditions that the rated operation of +/-800 kV and 10000MW extra-high voltage direct current is performed, the length of an ice melting section is 100km, and the conducting wire is taken into consideration according to the length of 8×1250mm 2, electrostatic coupling and ion flow field induced voltage are simultaneously considered, induced voltages in various working states are simulated:
| Working conditions of | Pole 1 | Pole 2 | Ground wire | Ground resistance kΩ | Induced voltage kV |
| 1 | 800 | -800 | One end is short-circuited and one side is suspended in the air | Without any means for | 0 |
| 2 | 0 | -800 | One end is short-circuited and one side is suspended in the air | Without any means for | 370 |
| 3 | 800 | -800 | One end is short-circuited and one side is high-resistance | 5 | 0 |
| 4 | 0 | -800 | One end is short-circuited and one side is high-resistance | 5 | 8.04 |
| 5 | 800 | -800 | One end is short-circuited and one side is high-resistance | 10 | 0 |
| 6 | 0 | -800 | One end is short-circuited and one side is high-resistance | 10 | 16.64 |
TABLE 1
The poles 1 and 2 are respectively a positive lead of direct current transmission and a negative lead of direct current transmission, when the pole 1 is 800kV extra-high voltage and the pole 2 is-800 kV extra-high voltage, the direct current transmission line is in a bipolar operation state, and the ground wire induction voltage which is not directly grounded is 0. When the pole 1 is 0 and the pole 2 is-800 kV extra-high voltage, the direct current transmission line is in a monopole running state, and under the condition that no grounding resistor is added, the induction voltage which is not directly grounded reaches 370kV. Consider that the maximum voltage can be reduced to 16.64kV after a 10k omega high resistance ground is used. The induced voltage is small, and the ice melting equipment is not damaged. Therefore, the technology can be considered to be practical after the induced voltage possibly generated during the monopolar operation is solved by the high-resistance grounding using the first grounding device 121 and the second grounding resistor device 122. Meanwhile, in order to further ensure safety, the operation ice melting of the direct current transmission line in bipolar operation can be preferably selected.
In one embodiment, as shown in fig. 3, the ice melting circuit further includes a first lightning arrester 131 and a second lightning arrester 132, a first end of the first lightning arrester 131 is connected to a first end of the ice melting power supply device 110, and a second end of the first lightning arrester 131 is grounded; the first end of the second lightning arrester 132 is connected to the second end of the ice melting power supply device 110, and the second end of the second lightning arrester 132 is grounded.
Specifically, the first ends of the first lightning arrester 131 and the second lightning arrester 132 are input ends, and the second ends of the first lightning arrester 131 and the second lightning arrester 132 are output ends. The input end of the first lightning arrester 131 is connected with the positive end of the ice melting power supply device 110, and the output end of the first lightning arrester 131 is grounded; the input end of the second lightning arrester 132 is connected with the negative end of the ice melting power supply device 110, and the output end of the second lightning arrester 132 is grounded.
In this embodiment, the first lightning arrester 131 and the second lightning arrester 132 are lightning arresters. It will be appreciated that by the first and second lightning arresters 131 and 132 being disposed close to the ice-melting power supply device 110, the ice-melting power supply device 110 can be protected from external invasion overvoltage.
In one embodiment, as shown in fig. 3, the ice melting circuit further includes a first grounding gap device 151 and a second grounding gap device 152, wherein a first end of the first grounding gap device 151 is connected with a head end of a tower down wire of a common ground wire of the section to be melted, and a second end of the first grounding gap device 151 is grounded; the first end of the second grounding gap device 152 is connected to the head end of the down-lead of the OPGW ground wire tower of the section to be melted, and the second end of the second grounding gap device 152 is grounded.
The first ends of the first grounding gap device 151 and the second grounding gap device 152 are input ends, and the second ends of the first grounding gap device 151 and the second grounding gap device 152 are output ends. Specifically, the input end of the first grounding gap device 151 is connected to the head end of the down-lead wire of the common ground wire tower of the section to be melted, and the output end of the first grounding gap device 151 is grounded; the input end of the second grounding gap device 152 is connected with the head end of the down-lead of the OPGW ground wire tower of the section to be melted, and the output end of the second grounding gap device 152 is grounded.
In one embodiment, the first grounding gap assembly 151 and the second grounding gap assembly 152 are each a parallel gap of about 100mm between ground insulators on a high voltage dc transmission tower. It will be appreciated that the first and second ground gap arrangements 151, 152 are insulator parallel gaps that protect the insulator on the one hand and breakdown in the event of lightning strikes, ground wire flashovers, induced voltages that are too high on the other hand, thereby protecting equipment and personal safety.
In one embodiment, as shown in fig. 3, the ice melting circuit further includes a first grounding switch 161 and a second grounding switch 162, wherein a first end of the first grounding switch 161 is connected to an end of a common ground wire, and a second end of the first grounding switch 161 is grounded; the first end of the second grounding switch 162 is connected to the end of the OPGW ground, and the second end of the second grounding switch 162 is grounded.
Further, the first ends of the first grounding switch 161 and the second grounding switch 162 are input ends, and the second ends of the first grounding switch 161 and the second grounding switch 162 are output ends. Specifically, the input end of the first grounding switch 161 is connected to the end of the common ground wire, and the output end of the first grounding switch 161 is grounded; the input end of the second grounding switch 162 is connected to the end of the OPGW ground wire, and the output end of the second grounding switch 162 is grounded.
In one embodiment, as shown in fig. 3, the first ice-melting switch 141, the second ice-melting switch 142, and the connection switch 170 are all isolating switches, and the first grounding switch 161 and the second grounding switch 162 are all grounding switches. When the ice melting circuit normally operates, an ice melting loop is formed by controlling the corresponding isolating switch and the switch to close and open, and the ice melting circuit is controlled by constant current from zero voltage.
In one embodiment, as shown in fig. 3, a high voltage dc uninterruptible ground ice melting apparatus is provided, the ice melting apparatus comprising an uninterruptible ground ice melting circuit as described above. The common ground wire and the OPGW ground wire are erected on the high-voltage direct-current transmission tower through ground wire insulators which are respectively connected with a first grounding gap device 151 and a second grounding gap device 152 in parallel. The head ends of the common ground wire and the OPGW ground wire tower down wire are respectively led to the lower part of the tower by using a cable or a bare wire, and then are respectively connected with the anode and the cathode of the ice melting power supply device 110 through a first ice melting switch 141 and a second ice melting switch 142. The tail ends of the common ground wire and the OPGW wire are respectively and electrically connected with the corresponding towers through a first grounding switch 161 and a second grounding switch 162, so that the grounding is realized.
In one embodiment, a method for melting ice on a high-voltage direct-current uninterruptible ground wire is provided, which is implemented based on the high-voltage direct-current uninterruptible ground wire ice melting device and includes: the first grounding switch and the second grounding switch are in a closing state when ice is not melted, and the connecting switch, the first ice melting switch and the second ice melting switch are in a separating state; the method comprises the following steps of continuously operating the high-voltage direct-current power transmission during ice melting, connecting a switch in the first step, connecting a first ice melting switch and a second ice melting switch in the second step, connecting a first grounding switch and a second grounding switch in the third step, and unlocking an ice melting device in the fourth step to start ice melting.
Specifically, during the ice melting process, the bipolar operation time of the direct current power transmission is selected first, the first ice melting switch 141, the second ice melting switch 142 and the connection switch 170 are closed to form an ice melting loop, then the first grounding switch 161 and the second grounding switch 162 are sequentially disconnected, the ground wire is not directly grounded at this time, the ice melting power supply device 110 is finally turned on, uninterrupted ice melting is started, and the ice melting is controlled by constant current from zero voltage.
It will be appreciated that if ice-breaking jump occurs during uninterrupted ice-melting, the conductive wire may be at risk of flashing through ice-breaking. Because the direct current is provided with an instantaneous ground fault restarting function, the power transmission is not affected by the accidental ground wire flashover. However, in order to suppress such risk, the problem can be solved by reducing the start value of melting ice and increasing the distance between the ground wires of the uninterrupted ice melting section in the design stage.
In long-distance direct current transmission, according to the conventional direct current ice melting thought, power failure is often required to melt ice. However, according to ice melting practice, the main ice melting work is concentrated in a small amount of medium-heavy ice areas. Considering that ice melting work stations are respectively arranged in each heavy ice area, the ground wire is led down in the ice melting season to be connected into ice melting equipment, and ice can be melted without stopping the operation of direct current. The whole ice melting process is safe and reliable: on one hand, by reducing the ice melting starting value, the ice removing jump is reduced to avoid the flashover of the conductive wire and the ground wire, even if the instant flashover of the conductive wire occurs, the direct current has the restarting function and cannot be stopped, and the equipment ensures the safety through equipment such as a grounding gap, a lightning arrester and the like; on the other hand, the grounding gap limits the induced voltage level, the induced voltage level is further reduced through high-resistance grounding, starting is conducted without power failure to melt ice when bipolar operation is preferentially considered in field operation, and even if monopolar operation occurs, the high-resistance grounding can ensure that the access induced voltage value is lower.
In the high-voltage direct-current uninterrupted ground wire ice melting equipment, a small ice melting workstation is arranged for an ice melting key section, a common ground wire and an OPGW ground wire are connected in series and then directly connected to an ice melting power supply device 110 in the workstation through a pole tower, direct current maintains normal operation, induced voltage is restrained through high-resistance grounding of a first grounding device 121 and a second grounding device 122, and the ice melting device is protected through a first gap device 151, a second gap device 152, a first lightning arrester 131 and a second lightning arrester 132. The ice melting pertinence is strong, and the common ground wire and the OPGW ground wire are simultaneously melted every time, so that the ice melting efficiency is high. The starting ice melting value can be properly reduced according to the needs, the lead wire flashover is avoided, the uninterrupted ice melting of the high-voltage direct-current power transmission ground wire is realized, the special ice melting is implemented for the key ice melting section, the lead wire is subjected to one-time ice melting, the ice melting efficiency is improved, the power failure loss is reduced, the power supply of the transmitting end is promoted, the power supply of the receiving end is ensured, and the economic benefit is remarkable.
The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.
The above examples illustrate only a few embodiments of the application, which are described in detail and are not to be construed as limiting the scope of the application. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the application, which are all within the scope of the application. Accordingly, the scope of protection of the present application is to be determined by the appended claims.
Claims (10)
1. The utility model provides a high voltage direct current does not have a power failure ground wire ice-melt circuit which characterized in that includes: the ice melting power supply device, the first ice melting switch, the second ice melting switch and the connecting switch; the first end of the ice melting power supply device is connected with the first end of the first ice melting switch, the second end of the ice melting power supply device is connected with the first end of the second ice melting switch, the second end of the first ice melting switch is connected with the head end of the pole tower down wire of the common ground wire of the section to be melted, the second end of the second ice melting switch is connected with the head end of the pole tower down wire of the OPGW of the section to be melted, the first end of the connecting switch is connected with the tail end of the common ground wire of the section to be melted, and the second end of the connecting switch is connected with the tail end of the OPGW ground wire of the section to be melted;
The ice melting power supply device is used for providing current required by ice melting of the common ground wire and the OPGW ground wire; the common ground wire and the OPGW ground wire are conducted when the connecting switch is closed, so that an ice melting loop is formed; when the first ice melting switch and the second ice melting switch are closed, the current output by the ice melting power supply device flows through the ice melting loop to melt ice.
2. The ice-melting circuit of claim 1, further comprising a first ground means and a second ground means, a first end of the first ground means being connected to a first end of the ice-melting power supply means, a second end of the first ground means being grounded; the first end of the second grounding device is connected with the second end of the ice melting power supply device, and the second end of the second grounding device is grounded.
3. The ice-melt circuit of claim 2, wherein said first and second grounding means are each resistances of 5kΩ -20kΩ resistance.
4. The ice-melt circuit of claim 1, further comprising a first lightning conductor and a second lightning conductor, wherein a first end of the first lightning conductor is connected to a first end of the ice-melt power supply, and a second end of the first lightning conductor is grounded; the first end of the second lightning arrester is connected with the second end of the ice melting power supply device, and the second end of the second lightning arrester is grounded.
5. The ice melting circuit of claim 1, further comprising a first ground clearance device and a second ground clearance device, wherein a first end of the first ground clearance device is connected to a head end of a common ground wire tower down conductor of the section to be melted, and a second end of the first ground clearance device is grounded; the first end of the second grounding gap device is connected with the head end of the down wire of the OPGW ground wire tower of the section to be melted, and the second end of the second grounding gap device is grounded.
6. The ice-melt circuit of claim 5, wherein the first and second ground gap devices are each a pole-on-ground insulator parallel discharge gap.
7. The ice-melting circuit of claim 1, further comprising a first grounding switch and a second grounding switch, wherein a first end of the first grounding switch is connected to an end of a common ground wire of the section to be melted, and a second end of the first grounding switch is grounded; and the first end of the second grounding switch is connected with the tail end of the OPGW ground wire of the section to be melted, and the second end of the second grounding switch is grounded.
8. The ice-melting circuit of claim 7, wherein the first ice-melting switch, the second ice-melting switch, and the connection switch are isolation switches, and the first ground switch and the second ground switch are ground knife switches.
9. A high voltage direct current uninterrupted ground wire ice melting device, which is characterized by comprising the high voltage direct current uninterrupted ground wire ice melting circuit as claimed in claims 1-8.
10. The high-voltage direct-current uninterrupted ground wire ice melting operation method is characterized by comprising the following steps of:
the first grounding switch and the second grounding switch are in a closing state when ice is not melted, and the connecting switch, the first ice melting switch and the second ice melting switch are in a separating state;
The method comprises the following steps of continuously operating the high-voltage direct-current power transmission during ice melting, connecting a switch in the first step, connecting a first ice melting switch and a second ice melting switch in the second step, connecting a first grounding switch and a second grounding switch in the third step, and unlocking an ice melting device in the fourth step to start ice melting.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211032258.0A CN115296246B (en) | 2022-08-26 | 2022-08-26 | High-voltage direct-current uninterrupted ground wire ice melting circuit, equipment and operation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211032258.0A CN115296246B (en) | 2022-08-26 | 2022-08-26 | High-voltage direct-current uninterrupted ground wire ice melting circuit, equipment and operation method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115296246A CN115296246A (en) | 2022-11-04 |
| CN115296246B true CN115296246B (en) | 2024-05-28 |
Family
ID=83831470
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211032258.0A Active CN115296246B (en) | 2022-08-26 | 2022-08-26 | High-voltage direct-current uninterrupted ground wire ice melting circuit, equipment and operation method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115296246B (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102611061A (en) * | 2012-03-13 | 2012-07-25 | 云南电力试验研究院（集团）有限公司电力研究院 | Single-pole ground loop type direct-current deicing method for overhead ground wire and OPGW (optical fiber composite overhead ground wire) |
| CN103247992A (en) * | 2013-05-07 | 2013-08-14 | 陈广生 | DC deicing method for overhead ground wires and OPGWs in electric transmission lines |
| CN106384989A (en) * | 2016-11-18 | 2017-02-08 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | Device and method for performing DC ice melting on overhead ground wire of power transmission line |
| WO2021223342A1 (en) * | 2020-05-08 | 2021-11-11 | 广东电网有限责任公司清远供电局 | On-line ice-melting appartus for power distribution network |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105730248B (en) * | 2016-03-03 | 2017-10-13 | 南京南瑞继保电气有限公司 | A kind of locomotive regenerative electric energy feedback system and control method for having ice-melt function concurrently |
-
2022
- 2022-08-26 CN CN202211032258.0A patent/CN115296246B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102611061A (en) * | 2012-03-13 | 2012-07-25 | 云南电力试验研究院（集团）有限公司电力研究院 | Single-pole ground loop type direct-current deicing method for overhead ground wire and OPGW (optical fiber composite overhead ground wire) |
| CN103247992A (en) * | 2013-05-07 | 2013-08-14 | 陈广生 | DC deicing method for overhead ground wires and OPGWs in electric transmission lines |
| CN106384989A (en) * | 2016-11-18 | 2017-02-08 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | Device and method for performing DC ice melting on overhead ground wire of power transmission line |
| WO2021223342A1 (en) * | 2020-05-08 | 2021-11-11 | 广东电网有限责任公司清远供电局 | On-line ice-melting appartus for power distribution network |
Non-Patent Citations (1)
| Title |
|---|
| 避雷线不停电直流融冰感应电压抑制方法研究;李宽宏等;《电力电容与无功补偿》;20210630;第42卷(第3期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115296246A (en) | 2022-11-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102255274B (en) | Direct-current de-icing method of overhead ground wire and composite optical fibre ground wire | |
| CN115498582B (en) | Uninterrupted ground wire direct-current deicing system and uninterrupted ground wire direct-current deicing method for ultra-high voltage transmission line | |
| CN101505053B (en) | Power line protection method based on user boundary circuit breaker devices | |
| CN101394073A (en) | Method and device for ice coating prevention and melt ice removing on electricity transmission and distribution line | |
| CN108899853B (en) | Live-line ice melting topological system and ice melting method thereof | |
| CN110605999B (en) | Measurement and control protection system and method for through type in-phase power supply network | |
| CN103296629A (en) | Ground wire DC (direct current) deicing method based on discharge gap insulator | |
| CN102856869A (en) | Wiring method for realizing direct-current deicing of ground wire of converter station | |
| CN106384989A (en) | Device and method for performing DC ice melting on overhead ground wire of power transmission line | |
| CN108923365B (en) | Transmission line wire suitable for live online ice melting and use method thereof | |
| CN108092182B (en) | Segmented ice melting method and system for high-voltage transmission line | |
| CN115296246B (en) | High-voltage direct-current uninterrupted ground wire ice melting circuit, equipment and operation method | |
| CN108923524A (en) | A kind of off-line UPS power control system | |
| CN201877234U (en) | Detachable lightning arrester | |
| CN115882412A (en) | Ice melting method for ground wire of wire without power failure | |
| CN116131191A (en) | Uninterrupted DC ice melting method for extra-high voltage DC line overhead ground wire | |
| CN203689973U (en) | High-resistance steel core ice-melting lead | |
| CN202363191U (en) | 10 kV line lighting arrester | |
| CN115864281A (en) | Live-line ice melting device and method for ultra-high voltage ground wire and optical fiber composite overhead ground wire | |
| CN109449865A (en) | A method of electrification Tear Down Deficiency low voltage surge arrester | |
| CN107482613A (en) | A kind of transformer station direct current system based on DC/DC isolation modules | |
| CN203895965U (en) | Line-side circuit capable of protecting electric locomotive high voltage transformer | |
| CN203607798U (en) | Ice melting device for earth electrode lead in ultra-high-voltage DC power transmission system | |
| CN201388042Y (en) | Central high-voltage switch equal-height cabinet | |
| CN210957782U (en) | 35kV transformer substation sectional bus system based on mixed superconducting current limiter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |