CN210608524U - High-voltage cable metal sheath circulation restraining system - Google Patents
High-voltage cable metal sheath circulation restraining system Download PDFInfo
- Publication number
- CN210608524U CN210608524U CN201921164144.5U CN201921164144U CN210608524U CN 210608524 U CN210608524 U CN 210608524U CN 201921164144 U CN201921164144 U CN 201921164144U CN 210608524 U CN210608524 U CN 210608524U
- Authority
- CN
- China
- Prior art keywords
- metal sheath
- suppressor
- series
- voltage cable
- resistance
- 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
Images
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
The utility model relates to a high tension cable metal sheath circulation restraint system, include, three-phase high tension cable line divides into a plurality of large sections, then divide into totally equal three subsection with each large section that divides into again, installs insulating joint between each subsection, recycles the cross interconnection case and will make the metal sheath of three subsection high tension cable in each large section alternately replace, installs metal sheath ground protector in the cross interconnection case, again ground after parallelly connecting the head and the end metal sheath layer simultaneously; wherein, a ring is sleeved at the tail end of each metal sheath, a coil is wound on the ring, and an insulating material is covered outside the coil; the resistance inductor pair is connected in series after the circular ring and the winding coil are sleeved; and then, after the metal sheaths of the three small sections of high-voltage cables are connected in parallel, the three small sections of high-voltage cables are connected in series with a grounding resistance suppressor, and finally, the three small sections of high-voltage cables are grounded. The utility model discloses in adopted comprehensive circulation suppression system, can obtain the optimal comprehensive suppression effect.
Description
Technical Field
The utility model relates to a supply the high tension cable in the distribution network, especially related to a high tension cable metal sheath circulation restraint system.
Background
The high-voltage cable has the advantages of high power supply reliability, small influence from external environmental factors, small occupied area, small influence on urban appearance environment and the like, and is widely applied to urban power transmission and distribution grids. The basic structure of the power cable comprises a wire core, an insulating layer and a protective layer. The main function of the protective layer is to protect the main insulating layer of the cable from mechanical damage and various environmental factors such as water, sunlight, biology, fire and the like during the laying and operation process so as to maintain the stable electrical performance of the cable, and therefore the state of the protective layer is directly related to the safe operation and the service life of the cable. Protective layers fall into three broad categories: metal protective layer, rubber and plastic protective layer, combined protective layer. The metal sheath is widely used because it has complete water-proof property, and can prevent water and other harmful substances from entering the cable insulation.
However, the cable load current and other currents induce a large induced voltage in the metal sheath, and when the line length is long, the induced voltage is very large, which causes a safety hazard, so that the metal sheath must be grounded, and a grounding current, also called sheath grounding circulating current, is formed on the metal sheath. Therefore, the existing high-voltage cable is usually grounded in a metal sheath cross-connection grounding manner to suppress induced voltage, and the cross-connection grounding is to perform cross transposition connection on the metal sheaths of the three-phase single-core cable of the three-section cable line through a coaxial cable and a cross-connection box (see an equivalent circuit diagram in fig. 1). Because the induced voltages on the three-phase cable sheath have phase difference of 120 degrees and are approximately equal in size, the induced voltages of the three sections can be mutually neutralized through the series connection of the three-phase cable sheath, so that the total induced voltage is controlled within a reasonable range, and the purpose of reducing the circulating current is further achieved.
According to the regulation of GB 50217 'design Specification of electric engineering cables': the maximum value of the normal induction potential at any point on the metal layer of the alternating current single-core power cable which is not directly grounded meets the following regulations: when safety measures capable of effectively preventing personnel from contacting the metal layer at will are not taken, the voltage is not more than 50V; except for the above, it should not be more than 300V. According to the actual electrification statistics of the cable sheath, the induced voltage of the cable sheath is generally below 20V and is lower than the specified 50V standard. However, the induced voltage of the metal sheath is unbalanced due to factors such as uneven load current, uneven cable segmentation, different cable arrangement modes, different cable phase intervals and the like, so that grounding circulation is generated. When the grounding circulation of the metal sheath is too large, a large amount of loss is caused, the temperature of the cable is increased, the transmission efficiency of the cable is reduced, and the service life of the cable is shortened. The generation and pre-control of the ground circulating currents must therefore be studied in order to obtain means for reducing the ground circulating currents.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide a high tension cable metal sheath circulation restraint system, its characterized in that:
the high-voltage cable metal sheath circulation restraining system comprises a three-phase high-voltage cable line, a plurality of high-voltage cable metal sheath circulation restraining system and a plurality of high-voltage cable metal sheath circulation restraining system, wherein the three;
wherein, a ring is sleeved at the tail end of each metal sheath, a coil is wound on the ring, and an insulating material is covered outside the coil; the resistance inductor pair is connected in series after the circular ring and the winding coil are sleeved; and then, after the metal sheaths of the three small sections of high-voltage cables are connected in parallel, the three small sections of high-voltage cables are connected in series with a grounding resistance suppressor, and finally, the three small sections of high-voltage cables are grounded.
Preferably, the resistance-inductance pair is formed by connecting a resistance suppressor and an inductance suppressor in series, wherein the cross-sectional area of the conductor is 60-80mm2And the impedance values are all 0.3-0.7 omega.
Preferably, the resistive-inductive pair seals the series resistive suppressor and inductive suppressor by potting epoxy within the insulating housing material, and electrically connects the series resistive suppressor and inductive suppressor to the metal sheath by a wire extending from the insulating housing material.
Preferably, the impedance value of the ground resistance suppressor is 0.3-0.7 Ω.
Preferably, the ground resistance suppressor is sealed by potting epoxy in an insulating housing material and is electrically connected to the pair of resistive inductors by leads extending from the insulating housing material.
Preferably, the insulating shell is made of a silicone rubber sleeve.
First, compared with the prior art in which there is a suppression system using a single series inductance suppressor or a series inductance and resistance suppressor, the effect of the single series inductance suppressor is easily affected by the sheath current and is unstable, and the effect of the series inductance and resistance is not ideal, and the utility model discloses in using a comprehensive circulating current suppression system of a series compensation inductance suppressor, a series resistance inductance pair suppressor and a series grounding resistance suppressor, it is possible to obtain an optimal comprehensive suppression effect.
Next, it was found in the calculation that the suppression effect is the best when the resistance value and the reactance value of the series connection are close to the equivalent impedance value of the sheath, and therefore the series compensation inductance suppressor, the series resistance inductance suppressor, and the series ground resistance suppressor were both numerically optimized to obtain the best suppression effect.
To sum up, the utility model discloses a high tension cable metal sheath circulation suppression system can obtain excellent circulation suppression effect.
Drawings
Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:
FIG. 1 is a schematic diagram of a three-section type cross-connection grounding equivalent circuit of a single-core high-voltage power cable without any circulating current suppressor;
fig. 2 is a schematic view of a grounding model of a medium-high voltage cable metal sheath circulation restraining system part of the present invention;
fig. 3 is a schematic diagram of the overall structure of the resistor-inductor pair suppressor.
In the figure, the position of the upper end of the main shaft,
1 is a series compensation inductance suppressor;
2 is a series resistance inductance pair suppressor;
3 is a series grounding resistance suppressor;
4 is a high-voltage cable metal sheath;
5 is a resistance-inductance pair connected in series;
6 is an insulating shell material;
7 is an epoxy casting body;
and 8 is a conducting wire.
Detailed Description
Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.
The utility model provides a high tension cable metal sheath circulation restraint system includes, three-phase high tension cable line falls into a plurality of big section, then divide into the three segment that equals completely with each big section that divides into again, installs insulating joint between each segment, and the metal sheath that utilizes the cross-connection case to come the three segment high tension cable in each big section carries out the transposition alternately, installs metal sheath ground connection protector in the cross-connection interconnection case, and the earthing is done again after connecting in parallel with the first end metal sheath layer simultaneously.
Specifically, a ring is sleeved at the tail end of each metal sheath 4, a coil is wound on the ring, and an insulating material is covered outside the coil to form the series compensation inductance suppressor 1; the ring is mainly used for supporting and winding the coil and has a magnetic conduction function, so that the coil is made of ferromagnetic materials, the coil is preferably a copper wire winding coil, the outside of the coil needs to be wholly soaked in paint, and meanwhile, in order to prevent damage caused by rat gnawing, environmental corrosion and the like, an insulating protective sleeve made of silicon rubber needs to be added outside the ring. When the series compensation inductance suppressor is actually prepared, firstly coating the outside of a ring wound with a coil with a wire coating paint, then coating impregnating paint, and finally coating insulating paint to cover, so that the suppressor conductor is prevented from being affected with damp, and inter-turn insulation is improved; after the whole body is dipped in paint, a silicon rubber insulating protective sleeve is added outside.
The annular ring and the winding coil are sleeved to form a series compensation inductance suppressor 1, and then a resistance inductance pair suppressor 2 is connected in series; wherein the pair of resistive-inductive suppressors 2 comprises a pair of resistive-inductive suppressors 5 connected in series, the pair of resistive-inductive suppressors 5 being sealed by potting epoxy 7 within the insulating housing material 6 and electrically connecting the series of resistive-and inductive suppressors to the metal sheath by wires 8 extending from the insulating housing material 6. The insulating housing material 6 is preferably a silicone rubber sleeve.
And then, the metal sheaths of the three small sections of high-voltage cables are connected in parallel, and then are connected with a grounding resistance suppressor 3 in series, and finally are grounded. The series ground resistor is also sealed by potting epoxy in the insulating housing material and is electrically connected to the resistor-inductor pair by a lead extending from the insulating housing material, which is not shown because of its similar overall structure to the resistor-inductor pair suppressor.
Considering that the current intensity of the cable core is often 200A in normal operation and the danger must be avoided if the insulation is damaged, the sectional area of the conductor is selected to be 60-80mm2Preferably, the impedance value is 0.3 to 0.7 Ω.
As described above, compared to the prior art in which a suppression system using a single series inductance suppressor or a series inductance and resistance suppressor is used, the present invention uses a comprehensive circulating current suppression system using a series compensation inductance suppressor and a series resistance inductance pair suppressor and a series ground resistance suppressor, and can obtain an optimal comprehensive suppression effect.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention should be covered by the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (6)
1. A high-voltage cable metal sheath circulation restraining system is characterized in that:
the high-voltage cable metal sheath circulation restraining system comprises a three-phase high-voltage cable line, a plurality of high-voltage cable metal sheath circulation restraining system and a plurality of high-voltage cable metal sheath circulation restraining system, wherein the three;
wherein, a ring is sleeved at the tail end of each metal sheath, a coil is wound on the ring, and an insulating material is covered outside the coil; the resistance inductor pair is connected in series after the circular ring and the winding coil are sleeved; and then, after the metal sheaths of the three small sections of high-voltage cables are connected in parallel, the three small sections of high-voltage cables are connected in series with a grounding resistance suppressor, and finally, the three small sections of high-voltage cables are grounded.
2. The high voltage cable metal sheath circulation suppression system of claim 1, wherein:
the resistance-inductance pair is formed by connecting a resistance suppressor and an inductance suppressor in series, wherein the sectional area of the conductor is 60-80mm2And the impedance values are all 0.3-0.7 omega.
3. The high voltage cable metal sheath circulation suppression system of claim 2, wherein:
the resistance-inductance pair seals the series-connected resistance suppressor and inductance suppressor by potting epoxy in the insulating housing material, and electrically connects the series-connected resistance suppressor and inductance suppressor to the metal sheath by a wire extending from the insulating housing material.
4. The high voltage cable metal sheath circulation suppression system of claim 1, wherein:
the impedance value of the grounding resistance suppressor is 0.3-0.7 omega.
5. The high voltage cable metal sheath circulation suppression system of claim 4, wherein:
the grounding resistance suppressor is sealed by pouring epoxy casting in an insulating shell material, and is electrically connected with the resistance inductor pair through a lead extending from the insulating shell material.
6. The high-voltage cable metal sheath circulation suppression system according to claim 3 or 5, wherein:
the insulating shell is made of a silicon rubber sleeve.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921164144.5U CN210608524U (en) | 2019-07-23 | 2019-07-23 | High-voltage cable metal sheath circulation restraining system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921164144.5U CN210608524U (en) | 2019-07-23 | 2019-07-23 | High-voltage cable metal sheath circulation restraining system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN210608524U true CN210608524U (en) | 2020-05-22 |
Family
ID=70692786
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201921164144.5U Active CN210608524U (en) | 2019-07-23 | 2019-07-23 | High-voltage cable metal sheath circulation restraining system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN210608524U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113949051A (en) * | 2021-10-08 | 2022-01-18 | 国网黑龙江省电力有限公司伊春供电公司 | Cable metal sheath circulating current restraining device and method |
-
2019
- 2019-07-23 CN CN201921164144.5U patent/CN210608524U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113949051A (en) * | 2021-10-08 | 2022-01-18 | 国网黑龙江省电力有限公司伊春供电公司 | Cable metal sheath circulating current restraining device and method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101802939B (en) | High voltage dry-type reactor for a voltage source converter | |
| JP6212465B2 (en) | Limiting device for interphase current and leakage current of submerged electrical equipment | |
| US6891303B2 (en) | High voltage AC machine winding with grounded neutral circuit | |
| PL185200B1 (en) | Transformer/reactor | |
| CN210490457U (en) | High-voltage cable metal sheath circulating current suppression system based on compensation inductance | |
| JP4801236B2 (en) | High voltage DC power cable and its submarine cable laying method | |
| CN110380377A (en) | A kind of synthesis circulation inhibition method of high-voltage cable metal sheath | |
| CN210608524U (en) | High-voltage cable metal sheath circulation restraining system | |
| JPH05325658A (en) | Electromagnetic shielding cable | |
| RU2201027C2 (en) | Series compensation in alternating-current machines | |
| EA001725B1 (en) | Power transformer/inductor | |
| CN111898319A (en) | Optimal calculation method for selection of high-voltage cable metal sheath circulating current inhibition mode | |
| Candela et al. | A comparison of special bonding techniques for transmission and distribution cables under normal and fault conditions | |
| Chennamadhavuni et al. | Investigation of transient and temporary overvoltages in a wind farm | |
| CN111884175A (en) | High-voltage cable metal sheath grounding circulation restraining method based on electromagnetic coupling method | |
| CN204596526U (en) | Earth leakage protective cable between a kind of electric wire | |
| CN113949062A (en) | Method for solving problem of sudden circulation change of multi-loop high-voltage single-core power cable sheath | |
| KR100571152B1 (en) | Sheath Current Suppressor for Underground Cables | |
| KR101282654B1 (en) | Economic power cable network system | |
| CN114270649A (en) | Protection of AC equipment | |
| JP6632954B2 (en) | Grounding system | |
| CN110299223B (en) | Composite return line | |
| CN212542147U (en) | Transformer and transformer system | |
| CN110402472B (en) | High-voltage winding and high-voltage electromagnetic induction equipment | |
| KR100894508B1 (en) | Power cable joints for high current cables |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |