CN111541231A - Method for enhancing fault current resistance of three-phase coaxial superconducting cable - Google Patents
Method for enhancing fault current resistance of three-phase coaxial superconducting cable Download PDFInfo
- Publication number
- CN111541231A CN111541231A CN202010424543.1A CN202010424543A CN111541231A CN 111541231 A CN111541231 A CN 111541231A CN 202010424543 A CN202010424543 A CN 202010424543A CN 111541231 A CN111541231 A CN 111541231A
- Authority
- CN
- China
- Prior art keywords
- superconducting cable
- branch
- fault current
- conventional lead
- superconducting
- 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.)
- Pending
Links
Images
Classifications
-
- 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
- H02H9/02—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess current
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/60—Superconducting electric elements or equipment; Power systems integrating superconducting elements or equipment
Abstract
The invention discloses a method for enhancing fault current resistance of a three-phase coaxial superconducting cable, which comprises the steps of connecting a three-phase coaxial superconducting cable branch and a conventional lead branch to a bus in parallel, and respectively connecting the three phases of the conventional lead branch and the three phases of the superconducting cable branch in parallel. By applying the method provided by the invention, when the branch of the superconducting cable breaks down, the short-circuit current exceeds the critical current of the superconducting cable, the superconducting cable is rapidly quenched, and the superconducting cable is in a high-resistance state. At this time, the impedance of the bypass conventional lead branch is smaller than that of the superconducting cable branch, so that the shunting effect is achieved, the fault current passing through the superconducting cable branch is greatly reduced, the fault current tolerance level of the superconducting cable system is improved, and the safety of the superconducting electrified conductor is protected. Compared with a series conventional reactor, the system loss under the normal operation condition is greatly reduced; compared with the superconducting current limiter, the cost is low, and the coordination is simple.
Description
Technical Field
The invention relates to the technical field of superconducting cables, in particular to a method for enhancing fault current resistance of a three-phase coaxial superconducting cable.
Background
The high-temperature superconducting cable has the advantages of low line loss, large transmission capacity, small occupied space of a corridor, environmental friendliness and the like, and provides an efficient, compact, reliable and green electric energy transmission mode for a power grid. Over a decade of development, great progress has been made in the fundamental research of superconducting cables. Considering a plurality of factors such as the continuous increase of the demand of electric energy, the rapid increase of the new energy ratio and the like, the superconducting power transmission technology which can simultaneously realize high-efficiency low-loss and large-capacity power transmission can play a greater role in the future, and has very wide application prospect.
The three-phase coaxial high-temperature superconducting cable has the advantages of compact structure, superconducting strip saving, smaller unit length cost, no electromagnetic interference to the outside under balanced operation and the like. The superconducting cable is a practical superconducting cable configuration with great development prospect. Since each functional layer of the three-phase conductor is wound on the same skeleton shaft, the flexibility of the three-phase coaxial superconducting cable is limited to a certain extent, generally speaking, a copper strip (wire) is wound close to the superconducting layer and used by the three-phase discrete or three-core superconducting cable to improve the fault current tolerance level of the superconducting cable, so that the technical scheme for protecting the superconducting strip material has no feasibility; once the copper stabilizing layers of the three-phase coaxial superconducting cable are synchronously wound, the flexibility of the electrified conductor of the three-phase coaxial superconducting cable is greatly limited, and the turning radius of the three-phase coaxial superconducting cable exceeds the minimum requirements of cable reel transportation and field laying.
For the above reasons, the three-phase coaxial superconducting cable itself has a weak fault current resistance, and an external current limiting measure is generally required to protect the superconducting tape from being damaged in the fault current process. Common external current limiting measures include a conventional reactor, a superconducting current limiter, and a hybrid combination of the two. However, connecting conventional reactors in series causes system losses under normal operating conditions and can degrade voltage quality. The use of superconducting current limiter has the problems of high cost, complex relay protection coordination and the like.
In summary, how to effectively solve the problems of weak fault current resistance of the three-phase coaxial superconducting cable and the like is a problem to be solved by those skilled in the art at present.
Disclosure of Invention
In view of the above, an object of the present invention is to provide a method for enhancing fault current resistance of a three-phase coaxial superconducting cable, which can effectively solve the problem that the fault current resistance of the three-phase coaxial superconducting cable is weak.
In order to achieve the purpose, the invention provides the following technical scheme:
a method for enhancing fault current resistance of a three-phase coaxial superconducting cable comprises the steps of connecting a three-phase coaxial superconducting cable branch and a conventional lead branch in parallel to a bus, and respectively connecting the three phases of the conventional lead branch and the three phases of the superconducting cable branch in parallel.
Preferably, in the method for enhancing the fault current resistance of the three-phase coaxial superconducting cable, the superconducting cable branch includes a superconducting cable body and connection terminals respectively connected to two ends of the superconducting cable body, and the superconducting cable body is connected to the bus through the connection terminals.
Preferably, in the method for enhancing the fault current resistance of the three-phase coaxial superconducting cable, current leads are respectively provided in the connection terminals corresponding to the three phases of the superconducting cable body, and the connection terminals are respectively connected to the three phases corresponding to the bus bars through the current leads.
Preferably, in the method for enhancing fault current resistance of the three-phase coaxial superconducting cable, the conventional lead branch includes a conventional lead body and terminal fittings respectively connected to two ends of the conventional lead body, and the conventional lead body is connected to the bus bar through the terminal fittings.
Preferably, in the method for enhancing fault current resistance of the three-phase coaxial superconducting cable, the conventional lead body is a three-core lead.
Preferably, in the method for enhancing the fault current resistance of the three-phase coaxial superconducting cable, the conventional lead body is a single-core lead, and the conventional lead body comprises three single-core leads to form a loop.
Preferably, in the method for enhancing fault current resistance of the three-phase coaxial superconducting cable, the conventional lead body is a copper wire.
When the method for enhancing the fault current resistance of the three-phase coaxial superconducting cable provided by the invention is applied, when the superconducting cable normally runs, almost all current passes through the superconducting cable branch because the impedance of the superconducting cable branch is far smaller than that of a conventional lead branch. When the branch of the superconducting cable breaks down, the short-circuit current exceeds the critical current of the superconducting cable, the superconducting cable is rapidly quenched, and the superconducting cable is in a high-resistance state. At this time, the impedance of the bypass conventional lead branch is smaller than that of the superconducting cable branch, so that the shunting effect is achieved, the fault current passing through the superconducting cable branch is greatly reduced, the fault current tolerance level of the superconducting cable system is improved, and the safety of the superconducting electrified conductor is protected. Compared with a series conventional reactor, the system loss under the normal operation condition is greatly reduced; compared with the superconducting current limiter, the cost is low, and the coordination is simple.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a schematic view of a wiring structure of a method of enhancing a fault current resistance of a three-phase coaxial type superconducting cable according to an embodiment of the present invention;
fig. 2 is an enlarged view of the inside of fig. 1.
The drawings are numbered as follows:
the superconducting cable comprises a bus 1, a conventional lead branch 2 and a superconducting cable branch 3; three phases 11 of the bus bar, a conventional lead body 21, a terminal joint 22, a superconducting cable body 31, a connection terminal 41, a current lead 42, and a connection line 5.
Detailed Description
The embodiment of the invention discloses a method for enhancing the fault current resistance of a three-phase coaxial superconducting cable, which improves the fault current tolerance level of a superconducting cable system and protects the safety of a superconducting electrified conductor.
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1, fig. 1 is a schematic diagram illustrating a connection structure of a method for enhancing fault current resistance of a three-phase coaxial superconducting cable according to an embodiment of the present invention.
In a specific embodiment, the method for enhancing the fault current resistance of the three-phase coaxial superconducting cable provided by the invention comprises the following steps:
s1: the superconducting cable branch 3 and the conventional lead branch 2 which are coaxial in three phases are connected in parallel to the bus bar 1, and the three phases of the conventional lead branch 2 and the three phases of the superconducting cable branch 3 are connected in parallel, respectively.
Here, the superconducting cable branch 3, i.e., the portion of the superconducting cable connected to the bus bar 1, is mainly directed to a three-phase coaxial superconducting cable in the superconducting cable branch 3 of the present application. Since the three-phase coaxial superconducting cable has a weak fault current resistance, a current limiting measure is required to be taken into consideration in the connection structure of the three-phase coaxial superconducting cable to protect the superconducting cable from being damaged in the fault current process.
The conventional lead branch 2 is a conventional lead arrangement corresponding to the superconducting cable branch 3, and the conventional meaning here is distinguished from superconductors, such as conventional copper leads and the like. The conventional lead branch 2 is connected in parallel with the superconducting cable branch 3, that is, two ends of the conventional lead branch 2 are also respectively connected to the bus 1, so that the conventional lead branch 2 is used as a protection structure for preventing the superconducting cable from being damaged in the fault current process.
The conventional lead branch 2 and the superconducting cable branch 3 are connected in parallel, and the three phases of the conventional lead branch 2 and the three phases of the superconducting cable branch 3 are connected in parallel to the bus bar 1, respectively. That is, the three phases of the conventional lead branch 2 are in one-to-one correspondence with the three phases of the superconducting cable branch 3, and are respectively connected in parallel to the bus bar 1.
When the method for enhancing the fault current resistance of the three-phase coaxial superconducting cable provided by the invention is applied, when the superconducting cable normally runs, almost all current passes through the superconducting cable branch 3 because the impedance of the superconducting cable branch 3 is far smaller than that of the conventional lead branch 2. When the superconducting cable branch 3 breaks down, the short-circuit current exceeds the critical current of the superconducting cable, the superconducting cable is rapidly quenched, and the superconducting cable is in a high-resistance state. At this time, the impedance of the bypass conventional lead branch 2 is smaller than that of the superconducting cable branch 3, so that a shunting effect is achieved, and the fault current passing through the superconducting cable branch 3 is greatly reduced, so that the fault current tolerance level of a superconducting cable system is improved, and the safety of a superconducting electrified conductor is protected. Compared with a series conventional reactor, the system loss under the normal operation condition is greatly reduced; compared with the superconducting current limiter, the cost is low, and the coordination is simple.
Specifically, the superconducting cable branch 3 includes a superconducting cable body 31 and connection terminals 41 connected to both ends of the superconducting cable body 31, respectively, and the superconducting cable body 31 is connected to the bus bar 1 through the connection terminals 41. The superconducting cable body 31, i.e., the three-phase coaxial superconducting cable tape, is provided with connection terminals 41 for facilitating connection thereof with the bus bar 1, i.e., both ends of the superconducting cable body 31 are connected with the bus bar 1 through the connection terminals 41, respectively. The connection terminal 41 plays a transitional role in connecting superconductivity and normal conductivity, connecting low temperature and normal temperature, and the like, and the specific structure thereof can be connected with reference to the conventional connection terminal 41 in the prior art, which is not limited specifically here.
Further, current leads 42 are provided in the connection terminals 41 corresponding to the three phases of the superconducting cable main body 31, respectively, and the connection terminals 41 are connected to the three phases corresponding to the bus bar 1 through the current leads 42, respectively. As shown in fig. 2, the main body of the three-phase coaxial superconducting cable branch 3 is a superconducting cable body 31, current leads 42 are provided in the connection terminal 41 corresponding to the three phases, respectively, and the current leads 42 are connected to the three phases 11 of the bus correspondingly, respectively, so that the three phases of the superconducting cable body 31 are connected to the three phases 11 of the bus in a one-to-one correspondence. Specifically, the current leads 42 may be connected to the three phases 11 of the bus bar by the connecting wires 5, respectively.
In the above embodiments, the conventional lead branch 2 includes the conventional lead body 21 and the end connectors 22 respectively connected to both ends of the conventional lead body 21, and the conventional lead body 21 is connected to the bus bar 1 through the end connectors 22. That is, the main body of the conventional lead branch 2 is a conventional lead body 21, and in order to facilitate connection thereof with the bus bar 1, a terminal joint 22 is provided, and the terminal joint 22 has connectors corresponding to the three phases 11 of the bus bar, respectively, so as to connect the three phases of the conventional lead body 21 with the three phases 11 of the bus bar in a one-to-one correspondence manner, respectively. The three phases of the superconducting cable body 31 and the three phases of the conventional lead body 21 are connected in parallel, respectively, by connecting the superconducting cable body 31 and the three phases 11 of the bus in one-to-one correspondence. The specific structure of the terminal fitting 22 can refer to the conventional fitting structure in the prior art, and is not limited herein.
Specifically, the conventional lead body 21 is a three-core lead. Three-core wires are commonly used for three-phase electricity. The conventional lead body 21 may also be a single core lead, and include three single core leads constituting a loop, as required. The single-core type conductor is only one conductor in one insulating layer, and for three-phase electricity, three single-core type conductors are required to form a loop. The form of the specific conventional lead body 21 may be set as needed.
Further, the conventional lead body 21 is a copper wire. The copper wire has the advantages of low resistivity, good ductility, high strength, fatigue resistance, good stability, oxidation resistance, corrosion resistance, large current-carrying capacity, low voltage loss, low heat productivity, low electrical loss and the like. And adopt the copper line, the impedance of superconductive cable branch 3 is far less than the impedance of conventional copper cable branch, and almost all electric current all passes through superconductive cable branch 3. When the superconducting cable branch 3 breaks down, the short-circuit current exceeds the critical current of the superconducting cable, the superconducting cable is rapidly quenched, and the superconducting cable is in a high-resistance state. At this time, the impedance of the bypass conventional copper cable branch is smaller than that of the superconducting cable branch 3, so that the shunting effect is achieved, the fault current passing through the superconducting cable branch 3 is greatly reduced, the fault current tolerance level of the superconducting cable system is improved, and the safety of a superconducting electrified conductor is protected. In addition, the energy absorbed by copper in the current limiting process can not be accumulated in a low-temperature environment, so that the time for the refrigeration system to restore the temperature of the superconductor to the operating temperature after quenching is reduced, and the reclosing operation is facilitated.
Other metals, metal alloys, or other materials having higher electrical conductivity and greater heat capacity may also be selected for the conventional lead body 21, as desired.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (7)
1. A method for enhancing fault current resistance of a three-phase coaxial superconducting cable is characterized by comprising the steps of connecting three-phase coaxial superconducting cable branches and a conventional lead branch to a bus in parallel, and connecting three phases of the conventional lead branch and three phases of the superconducting cable branches in parallel respectively.
2. The method of enhancing a fault current resistance of a three-phase coaxial superconducting cable according to claim 1, wherein the superconducting cable branch includes a superconducting cable body and connection terminals respectively connected to both ends of the superconducting cable body, the superconducting cable body being connected to the bus bar through the connection terminals.
3. The method of enhancing a fault current resistance of a three-phase coaxial superconducting cable according to claim 2, wherein current leads are provided in the connection terminals corresponding to three phases of the superconducting cable body, respectively, and the connection terminals are connected to the three phases corresponding to the bus bars through the current leads, respectively.
4. The method for enhancing fault current resistance of a three-phase coaxial superconducting cable according to any one of claims 1 to 3, wherein the conventional lead branch includes a conventional lead body and terminal fittings respectively connected to both ends of the conventional lead body, the conventional lead body being connected to the bus bar through the terminal fittings.
5. The method for enhancing fault current resistance of a three-phase coaxial superconducting cable according to claim 4, wherein the conventional lead body is a three-core lead.
6. The method for enhancing fault current resistance of a three-phase coaxial superconducting cable according to claim 4, wherein the conventional lead body is a single core lead, and the three single core leads are included to form a loop.
7. The method for enhancing fault current resistance of a three-phase coaxial superconducting cable according to claim 4, wherein the conventional lead body is a copper wire.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010424543.1A CN111541231A (en) | 2020-05-19 | 2020-05-19 | Method for enhancing fault current resistance of three-phase coaxial superconducting cable |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010424543.1A CN111541231A (en) | 2020-05-19 | 2020-05-19 | Method for enhancing fault current resistance of three-phase coaxial superconducting cable |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111541231A true CN111541231A (en) | 2020-08-14 |
Family
ID=71979486
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010424543.1A Pending CN111541231A (en) | 2020-05-19 | 2020-05-19 | Method for enhancing fault current resistance of three-phase coaxial superconducting cable |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111541231A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112736924A (en) * | 2020-12-11 | 2021-04-30 | 深圳供电局有限公司 | Power transmission system |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101675566A (en) * | 2007-02-09 | 2010-03-17 | 美国超导公司 | High temperature superconducting malfunction current limiter device in parallel |
| CN101840775A (en) * | 2009-03-13 | 2010-09-22 | 尼克桑斯公司 | Current limiter |
| CN105103397A (en) * | 2013-04-01 | 2015-11-25 | 住友电气工业株式会社 | Current-limiting/flow control device |
| CN111029035A (en) * | 2019-12-26 | 2020-04-17 | 国网江苏省电力有限公司 | High-temperature superconducting cable structure and high-temperature superconducting cable system |
-
2020
- 2020-05-19 CN CN202010424543.1A patent/CN111541231A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101675566A (en) * | 2007-02-09 | 2010-03-17 | 美国超导公司 | High temperature superconducting malfunction current limiter device in parallel |
| CN101840775A (en) * | 2009-03-13 | 2010-09-22 | 尼克桑斯公司 | Current limiter |
| CN105103397A (en) * | 2013-04-01 | 2015-11-25 | 住友电气工业株式会社 | Current-limiting/flow control device |
| CN111029035A (en) * | 2019-12-26 | 2020-04-17 | 国网江苏省电力有限公司 | High-temperature superconducting cable structure and high-temperature superconducting cable system |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112736924A (en) * | 2020-12-11 | 2021-04-30 | 深圳供电局有限公司 | Power transmission system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7598458B2 (en) | Super-conductive cable | |
| CA2677680C (en) | Hts wire | |
| US20080194411A1 (en) | HTS Wire | |
| US7724482B2 (en) | Parallel HTS transformer device | |
| KR101142124B1 (en) | Parallel connected hts fcl device | |
| JP2002534052A (en) | Power transmission system using superconductor | |
| US20040256144A1 (en) | Phase split structure of multiphase superconducting cable | |
| CN111029035A (en) | High-temperature superconducting cable structure and high-temperature superconducting cable system | |
| Zhang et al. | Testing results for the cable core of a 360 m/10 kA HTS DC power cable used in the electrolytic aluminum industry | |
| CN111541231A (en) | Method for enhancing fault current resistance of three-phase coaxial superconducting cable | |
| CN114220601B (en) | High-reliability superconducting cable structure | |
| Shiohara et al. | Demonstration test of triaxial superconducting cable system installed in commercial chemical plant grid | |
| CN218352256U (en) | Power standby power supply circuit for extra-high voltage converter station | |
| KR20110122368A (en) | The bus-connection system using the cicc superconduction magnet for protecting power system from fault current when connecting bus of the substation | |
| CN116072345A (en) | Support framework and conductor structure of superconducting cable through conductor | |
| Sytnikov et al. | The creation of high-temperature superconducting cables of megawatt range in Russia | |
| CN114613544A (en) | High-reliability superconducting cable system | |
| Seo et al. | A Feasibility Study of Smart High-Temperature Superconducting Cable to Improve Stability of KEPCO System |
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 | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200814 |