CN110994623A - 10kV superconducting loop closing operation method - Google Patents
10kV superconducting loop closing operation method Download PDFInfo
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- CN110994623A CN110994623A CN201911362547.5A CN201911362547A CN110994623A CN 110994623 A CN110994623 A CN 110994623A CN 201911362547 A CN201911362547 A CN 201911362547A CN 110994623 A CN110994623 A CN 110994623A
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- 238000000034 method Methods 0.000 title claims abstract description 32
- 239000000835 fiber Substances 0.000 claims 1
- 230000036316 preload Effects 0.000 claims 1
- 238000010586 diagram Methods 0.000 description 7
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 239000013307 optical fiber Substances 0.000 description 2
- 230000009977 dual effect Effects 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/04—Circuit arrangements for ac mains or ac distribution networks for connecting networks of the same frequency but supplied from different sources
- H02J3/06—Controlling transfer of power between connected networks; Controlling sharing of load between connected networks
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/22—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for distribution gear, e.g. bus-bar systems; for switching devices
- H02H7/226—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for distribution gear, e.g. bus-bar systems; for switching devices for wires or cables, e.g. heating wires
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- 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
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Abstract
The invention discloses a 10kV superconducting closed loop operation method, which comprises the following steps: step S1, measuring the current limiting value of the 10kV superconducting cable according to the N-1 guide rule requirement of the looped network operation, and judging whether the cable power flow meets the power safety and stability guide rule requirement; step S2, judging the short-circuit current level of the 110kV line and the 110kV line bus of the closed-loop operation system; step S3, configuring the protection of the 110kV line and the 10kV superconducting cable in the related ring network; and step S4, detecting and configuring the spare power automatic switching device of the related disconnecting point 110kV line and the 10kV superconducting cable bus. By implementing the invention, the power supply reliability is improved, N-1 is satisfied in a ring, and the load safety is ensured; double-loop power supply is formed, and power failure of a user caused by single power failure is avoided.
Description
Technical Field
The invention belongs to the technical field of superconduction, and relates to a 10kV superconducting closed-loop operation method.
Background
The high-temperature superconducting cable has the advantages of high capacity, low loss, energy conservation, environmental protection and the like, so that the superconducting cable has good application prospects in the aspects of improving the transmission capacity of a power grid, upgrading the existing power system and constructing a new power system, and has a certain advantage compared with the conventional cable.
At present, a superconducting cable is still in an immature stage, is influenced by problems of superconducting tapes, a cable installation process, refrigeration and the like, is poor in power supply reliability, and still has the risk of voltage loss of a user caused by fault tripping.
The traditional 10kV superconducting cable generally adopts an open-loop operation mode as the conventional cable. The 10kV superconducting cable and the 110kV line are mutually standby, so that the problem of reliability reduction caused by the split operation of the 110kV transformer substation is solved. In order to reduce the voltage loss risk of the whole station, the 110kV transformer substation generally adopts split operation, two 110kV lines are respectively used for 2 main transformers and 1 main transformer, the voltage reduction utilizes 10kV backup power automatic switching to support each other, but correspondingly, the risk that the 110kV lines for the two main transformers cause the voltage loss of 2 sections of 10kV buses exists, and the power supply reliability is reduced.
Disclosure of Invention
The technical problem to be solved by the embodiment of the invention is to provide a 10kV superconducting loop-closing operation method, and solve the problems that a 10kV superconducting cable and a 110kV line electromagnetic ring network are low in operation reliability and poor in load safety, and a fault of one line can cause a fault of the other line.
The invention provides a 10kV superconducting closed-loop operation method, which comprises the following steps:
step S1, measuring the current limiting value of the 10kV superconducting cable according to the N-1 guide rule requirement of the looped network operation, and judging whether the cable power flow meets the power safety and stability guide rule requirement;
step S2, judging the short-circuit current level of the 110kV line and the 110kV line bus of the closed-loop operation system;
step S3, configuring the protection of the 110kV line and the 10kV superconducting cable in the related ring network;
and step S4, detecting and configuring the spare power automatic switching device of the related disconnecting point 110kV line and the 10kV superconducting cable bus.
Further, in step S1, the specific process of determining whether the power flow of the cable meets the requirement of power safety and stability rules is to determine that the power flow of the 110 line and the 10kV superconducting cable is smaller than the maximum power limit of the superconducting cable body, such as the limit of the superconducting cross section of the power flow, and a pre-load-turning measure is required.
Further, in step S2, the specific process of determining the short-circuit current level of the 110kV line and the 110kV line bus of the closed-loop operation system is to check the short-circuit current of the 110kV bus during the closed-loop operation, determine whether the short-circuit current level is not greater than the maximum interruption capacity of the switch, and add a 10kV current-limiting reactor if the short-circuit current is greater than the maximum interruption capacity of the switch.
Further, in step S3, the arrangement of the 110kV line and the 10kV superconducting cable protection in the related ring network specifically includes a doubling of the 110kV line and the 10kV superconducting cable arrangement for optical fiber differential protection, a doubling of the 110kV bus bar protection in the B station arrangement, and a doubling of the 10kV 3M, B station 10kV 3M, B station 10kV4M arrangement for 10kV bus bar protection in the a station arrangement.
Further, in step S3, the protection configuration of the 110kV line and the 10kV superconducting cable in the related ring network specifically includes backup protection configuration distance, overcurrent, and direction protection of the 10kV superconducting cable.
Further, in step S3, the protection configuration of the 110kV line and the 10kV superconducting cable in the related ring network specifically includes that the a station 10kV 3M, B station 10kV 3M, B station 10kV4M feeder is configured with conventional overcurrent and zero sequence protection and distance protection.
Further, in step S4, the specific process of detecting and configuring the backup power automatic switching device of the 110kV line and the 10kV superconducting cable bus at the relevant disconnection point is to detect whether both the B station 10kV backup power automatic switching and the a station 10kV backup power automatic switching meet the 10kV4M operation requirement, and if not, perform upgrade and update.
Further, the 10kV superconducting cable has a resistance of 10% of that of a conventional cable.
The embodiment of the invention has the following beneficial effects:
the embodiment of the invention provides a 10kV superconducting closed-loop operation method, which adopts an electromagnetic looped network to operate, improves the power supply reliability, meets N-1 in the loop, and ensures the load safety; the power supply reliability of the 110kV transformer substation is improved, the power supply safety of the central area is guaranteed, double-loop power supply is formed, and power failure of a user caused by single power failure is avoided.
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 introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is within the scope of the present invention for those skilled in the art to obtain other drawings based on the drawings without inventive exercise.
Fig. 1 is a schematic main flow diagram of an embodiment of a 10kV superconducting loop operation method provided by the present invention.
Fig. 2 is a schematic diagram of superconducting closed-loop operation of a medium-low voltage distribution network according to an embodiment of the 10kV superconducting closed-loop operation method provided by the invention.
Fig. 3 is a schematic diagram of a closed loop operation mode flow of an embodiment of a 10kV superconducting closed loop operation method provided by the invention.
Fig. 4 is a schematic diagram of a calculation result of 10kV 3M of a station a or a 10kV line outlet short-circuit current connected thereto according to an embodiment of the 10kV superconducting loop operation method provided by the present invention.
Fig. 5 is a schematic diagram of a calculation result of a 10kV 3M short-circuit current at a B station or an outlet of a 10kV line connected thereto according to an embodiment of the 10kV superconducting loop operation method provided by the present invention.
Fig. 6 is a schematic diagram of a power grid protection configuration suitable for current carrying capacity of a superconducting cable according to an embodiment of the 10kV superconducting loop operation method provided by the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings.
As shown in fig. 2, the superconducting closed loop operation mode of the medium-low voltage distribution network is provided by the invention. Besides the conventional power supply from a 220kV A substation to a 110kV B substation, a 10kV high-temperature superconducting alternating-current cable line with the length of about 430m is newly built in a 10kV #4 bus of the 110kV B station, the 10kV #3 bus of the 220kV A station and the 110kV B station 10kV #4 bus are connected, the transmission capacity of the newly built line is considered according to 43MVA, the 10kV superconducting cable and the 110kV line electromagnetic ring network operate, and the electromagnetic ring network operation is kept to meet 4 aspects of power flow, short-circuit current, relay protection, automatic backup power switching and the like.
As shown in fig. 1, a main flow diagram of an embodiment of a 10kV superconducting loop operation method provided by the present invention is shown, in the embodiment, the method includes the following steps:
step S1, measuring the current limiting value of the 10kV superconducting cable according to the N-1 guide rule requirement of the looped network operation, and judging whether the cable power flow meets the power safety and stability guide rule requirement;
in a specific embodiment, as shown in fig. 3, the specific process of determining whether the power flow of the cable meets the power safety and stability guideline is to determine that the power flows of the 110 line and the 10kV superconducting cable are smaller than the maximum power limit of the superconducting cable body, such as the limit of the superconducting section of the power flow, a pre-load-transfer measure is required to be taken to ensure that no cascading failure occurs to the power flow in the ring network; the reasonable distribution of the power flow of the closed-loop related equipment is ensured, and the safe and stable guiding rule requirements of the electric power are ensured to be met by means of controlling the load in advance and the like.
Step S2, judging the short-circuit current level of the 110kV line and the 110kV line bus of the closed-loop operation system;
in a specific embodiment, as shown in fig. 4 and 5, the superconducting cable is calculated as 10% of the impedance of the conventional cable, the short-circuit current of the 110kV bus and the short-circuit of the 10kV bus are checked during the closed-loop operation, and the specific process of determining the short-circuit current level of the 110kV bus and the 110kV bus of the closed-loop operation system is to check the short-circuit current of the 110kV bus during the closed-loop operation, determine whether the short-circuit current level is not greater than the maximum interruption capacity of the switch, and add a 10kV current-limiting reactor if the short-circuit current is greater than the maximum interruption capacity of
Step S3, configuring the protection of the 110kV line and the 10kV superconducting cable in the related ring network;
in a specific embodiment, as shown in fig. 6, for a power grid protection configuration suitable for the current carrying capability of the superconducting cable, in order to ensure the ring network to operate, 110kV and 10kV protection configurations in the related ring network need to be configured with reference to 220kV equipment, which is mainly a near backup dual configuration. Mainly comprises the following steps: the 110kV line and the 10kV superconducting cable are provided with double optical fiber differential protection, the station B is provided with double 110kV bus differential protection, and the station A is provided with 10kV 3M, B station 10kV 3M, B station 10kV4M and is provided with double 10kV bus differential protection; backup protection configuration distance, overcurrent and direction protection of the 10kV superconducting cable; a10 kV 3M, B10 kV 3M, B10 kV4M feeder of the A station is configured with conventional overcurrent and zero sequence protection and distance protection.
Step S4, detecting and configuring a spare power automatic switching device of a related disconnection point 110kV line and a 10kV superconducting cable bus;
in a specific embodiment, the configuration of the backup power automatic switching device is to meet the condition that 110kV and 10kV bus-tie backup power automatic switching devices are configured at related disconnection points during open-loop operation, and the specific process of detecting and configuring the backup power automatic switching device of a 110kV line and a 10kV superconducting cable bus of the related disconnection points is to detect whether 10kV backup power automatic switching of a B station and 10kV backup power automatic switching of an A station meet 10kV4M operation requirements or not, and if not, upgrade and update are carried out.
For further details, reference may be made to the preceding description of the drawings, which are not described in detail herein.
The embodiment of the invention has the following beneficial effects:
the embodiment of the invention provides a 10kV superconducting closed-loop operation method, which adopts an electromagnetic looped network to operate, improves the power supply reliability, meets N-1 in the loop, and ensures the load safety; the power supply reliability of the 110kV transformer substation is improved, the power supply safety of the central area is guaranteed, double-loop power supply is formed, and power failure of a user caused by single power failure is avoided.
While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
Claims (8)
1. A10 kV superconducting loop-closing operation method is characterized by comprising the following steps:
step S1, measuring the current limiting value of the 10kV superconducting cable according to the N-1 guide rule requirement of the looped network operation, and judging whether the cable power flow meets the power safety and stability guide rule requirement;
step S2, judging the short-circuit current level of the 110kV line and the 110kV line bus of the closed-loop operation system;
step S3, configuring the protection of the 110kV line and the 10kV superconducting cable in the related ring network;
and step S4, detecting and configuring the spare power automatic switching device of the related disconnecting point 110kV line and the 10kV superconducting cable bus.
2. The method as claimed in claim 1, wherein the step S1 for determining whether the cable power flow satisfies the power safety and stability guideline requires that the power flow of the 110 line and 10kV superconducting cable is less than the maximum power limit of the superconducting cable body, such as the limit of the superconducting cross section of the power flow, and a pre-load transfer measure is required.
3. The method as claimed in claim 2, wherein in step S2, the specific process of determining the short-circuit current level of the 110kV line and the 110kV line bus of the closed-loop operation system is to check the short-circuit current of the 110kV bus during the closed-loop operation, determine whether the short-circuit current level is not greater than the maximum interruption capacity of the switch, and add a 10kV current-limiting reactor if the short-circuit current is greater than the maximum interruption capacity of the switch.
4. The method as claimed in claim 3, wherein in step S3, the 110kV line and 10kV superconducting cable protection configuration in the related ring network specifically includes a fiber differential protection with a dualized 110kV line and 10kV superconducting cable configuration, a 110kV bus differential protection with a dualized B-station configuration, and a 10kV 3M, B station, 10kV 3M, B station, and a 10kV 4M-station configuration with a dualized 10kV bus differential protection.
5. The method of claim 4, wherein in step S3, the 110kV line and 10kV superconducting cable protection configuration in the related ring network specifically comprises a backup protection configuration distance, an overcurrent and direction protection of the 10kV superconducting cable.
6. The method of claim 5, wherein in step S3, the 110kV line and 10kV superconducting cable protection configuration in the related ring network specifically includes an A station 10kV 3M, B station 10kV 3M, B station 10kV4M feeder line configuration conventional overcurrent and zero sequence protection and a configuration distance protection.
7. The method as claimed in claim 6, wherein in step S4, the specific process of detecting and configuring the backup power automatic switching device of the 110kV line and the 10kV superconducting cable bus at the relevant disconnection point is to detect whether both the B station 10kV backup power automatic switching device and the a station 10kV backup power automatic switching device meet the 10kV4M operation requirement, and if not, perform upgrade and update.
8. The method of any of claims 1 to 7, wherein the 10kV superconducting cable has a resistance of 10% of the resistance of a conventional cable.
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CN112736924A (en) * | 2020-12-11 | 2021-04-30 | 深圳供电局有限公司 | Power transmission system |
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