CN108092240A - Single valve group puts into method online in a kind of flexible direct current system - Google Patents
Single valve group puts into method online in a kind of flexible direct current system Download PDFInfo
- Publication number
- CN108092240A CN108092240A CN201611043460.8A CN201611043460A CN108092240A CN 108092240 A CN108092240 A CN 108092240A CN 201611043460 A CN201611043460 A CN 201611043460A CN 108092240 A CN108092240 A CN 108092240A
- Authority
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- China
- Prior art keywords
- valve group
- single valve
- direct current
- parallel
- breaker
- 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.)
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Classifications
-
- 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
- H02H7/26—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured
- H02H7/261—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured involving signal transmission between at least two stations
- H02H7/262—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured involving signal transmission between at least two stations involving transmissions of switching or blocking orders
-
- 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
- H02H7/26—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured
- H02H7/267—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured for parallel lines and wires
-
- 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
- H02H7/26—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured
- H02H7/268—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured for dc systems
-
- 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
- H02J3/36—Arrangements for transfer of electric power between ac networks via a high-tension dc link
-
- 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
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Driving Mechanisms And Operating Circuits Of Arc-Extinguishing High-Tension Switches (AREA)
Abstract
The present invention discloses single valve group in a kind of flexible direct current system and puts into method online, is related to technical field of electric power transmission, for when the transverter major loop troubleshooting or dielectric level of series connection recover, the transverter that rapidly will move out to put into operation online again.Single valve group puts into method and includes online in the flexible direct current system：Will single valve group be put into it is in parallel with breaker and bypass isolating switch respectively；Disconnect the bypass isolating switch in parallel with single valve group to be put into；Unlock single valve group to be put into；The breaker in parallel with single valve group to be put into is disconnected, single valve group to be put into is made to put into operation, has been put into single valve group；It keeps the DC voltage that the i-th end has put into single valve group place current conversion station constant, repeats the above steps, complete the input of i+1 end single valve group to be put into.Single valve group puts into method for putting into single valve group online online in flexible direct current system provided by the invention.
Description
Technical field
The present invention relates to single valve groups in technical field of electric power transmission more particularly to a kind of flexible direct current engineering to put into method online.
Background technology
At present, line commutation transverter D.C. high voltage transmission (line commutated converter based high
Voltage direct current, are abbreviated as LCC-HVDC) ripe answer has been obtained in large capacity, remote power transmission engineering
With still, since LCC-HVDC uses thyristor as the change of current device AC system of some strength to be needed to prop up in commutation
It holds, it is difficult to overcome the problems, such as that commutation failure occurs for inverter side completely.Compared with LCC-HVDC, voltage source converter high-voltage dc transmission
Electric (voltage source converter based high voltage direct current, be abbreviated as VSC-HVDC)
Due to using based on igbt converter valve, (insulated gate bipolar transistor, are abbreviated as
IGBT all-controlling power electronics device), there is no the problem of commutation failure.And due to voltage source converter (voltage
Source converter, are abbreviated as VSC) structure there is two level blocks, diode clamp bit architecture or modular multilevel to change
Device (modular multilevel converter, MMC) structure etc. is flowed, wherein, MMC has modular construction, switching frequency
Low, autgmentability is strong and the features such as without filter, and therefore, MMC structures have become high voltage large capcity VSC-HVDC engineerings
The trend of application.
However, the defects of VSC-HVDC is there is also can not be ignored, when Practical Project is run, when some valve in current conversion station
When group breaks down, due to being serially connected in current conversion station between each valve group, make entire current conversion station forced outage, system is in paralysis
Paralysis state, and, it is necessary to which longer time is spent to restart system after troubleshooting.
The content of the invention
It is an object of the invention to provide single valve groups in a kind of flexible direct current system to put into method online, for when series connection
During transverter major loop troubleshooting, the transverter that rapidly will move out puts into operation online again.
To achieve these goals, the present invention provides following technical solution：
Single valve group puts into method online in a kind of flexible direct current system, and flexible direct current system includes at least two current conversion stations,
Two neighboring current conversion station is connected by DC power transmission line, and each current conversion station includes the valve group of series connection；It is single in flexible direct current system
Valve group puts into method online to be included：
Step S1：I-th end single valve group to be put into is in parallel with breaker and bypass isolating switch respectively；
Step S3：The bypass isolating switch in parallel with the i-th end single valve group to be put into is disconnected, flows through bypass isolating switch
Electric current is transferred to the breaker in parallel with the i-th end single valve group to be put into；
Step S4：The i-th end single valve group to be put into is unlocked, remains the voltage of the single valve group to be put into of the i-th end after unlock
Zero；
Step S5：The breaker in parallel with the i-th end single valve group to be put into is disconnected, makes the i-th end single valve group input fortune to be put into
Row completes the input of the i-th end single valve group to be put into, obtains the i-th end and put into single valve group；
Step S6：Keep the DC voltage that the i-th end has put into single valve group place current conversion station constant, repeatedly step S1-S5, complete
Into the input of i+1 end single valve group to be put into.
Compared with prior art, in flexible direct current system provided by the invention single valve group put into online method have have as follows
Beneficial effect：
Single valve group is online in input method in flexible direct current system provided by the invention, series connection transverter major loop therefore
When barrier excludes or dielectric level recovers, it is only necessary to single valve group to be put into is in parallel with breaker and bypass isolating switch respectively, so
It can make after input single valve group after breaking down, single valve group to be put into is bypassed by bypass isolating switch, makes operating current through bypass
Disconnecting switch is formed into a loop, and the entire current conversion station that will not stop transport, and then when putting into the single valve group, is treated by disconnecting with the i-th end
The bypass isolating switch of single valve group parallel connection is put into, then unlocks the i-th end single valve group to be put into, then disconnects and treats that input is single with the i-th end
The breaker of valve group parallel connection, you can complete putting into operation for the i-th end single valve group to be put into, obtain the i-th end and put into single valve group, so
The present invention is constant by keeping the DC voltage that the i-th end has put into single valve group place current conversion station afterwards, is according to above-mentioned similary step
Can complete the input of i+1 end single valve group to be put into, so as in the transverter major loop troubleshooting of series connection, can rapidly by
The transverter exited puts into operation online again, improves the reliability of flexible direct current power transmission system, makes flexible direct current power transmission system
Continuous service.
Description of the drawings
Attached drawing described herein is used for providing a further understanding of the present invention, forms the part of the present invention, this hair
Bright schematic description and description does not constitute improper limitations of the present invention for explaining the present invention.In the accompanying drawings：
Fig. 1 is the flow chart that single valve group puts into method online in flexible direct current system provided in an embodiment of the present invention；
Fig. 2 is corresponding to put into the step S3 of method online with single valve group in flexible direct current system provided in an embodiment of the present invention
The i-th end single valve group to be put into wiring diagram；
Fig. 3 is corresponding to put into the step S5 of method online with single valve group in flexible direct current system provided in an embodiment of the present invention
The i-th end put into the wiring diagram of single valve group.
Reference numeral：
B1- breaker, S1- bypass isolating switch；
IB- breaker branch current, IFM- transverter exports electric current；
IS- bypass isolating switch branch current.
Specific embodiment
Method is put into online in order to further illustrate single valve group in flexible direct current system provided in an embodiment of the present invention, below
It is described in detail with reference to Figure of description.
Online in input method, flexible direct current system is included at least single valve group in flexible direct current system provided in this embodiment
Two current conversion stations, two neighboring current conversion station are connected by DC power transmission line, and each current conversion station includes the valve group of series connection, such as Fig. 1
Shown, single valve group puts into method and includes online in flexible direct current system：
Step S1：I-th end single valve group to be put into is in parallel with breaker and bypass isolating switch respectively；
Step S3：The bypass isolating switch in parallel with the i-th end single valve group to be put into is disconnected, the bypass is flowed through and keeps apart
The electric current of pass is transferred to the breaker in parallel with the i-th end single valve group to be put into；
Step S4：The i-th end single valve group to be put into is unlocked, remains the voltage of the single valve group to be put into of the i-th end after unlock
Zero；
Step S5：The breaker in parallel with the i-th end single valve group to be put into is disconnected, makes the i-th end single valve group input fortune to be put into
Row completes the input of the i-th end single valve group to be put into, obtains the i-th end and put into single valve group；
Step S6：Keep the DC voltage that the i-th end has put into single valve group place current conversion station constant, repeatedly step S1-S5, complete
Into the input of i+1 end single valve group to be put into.
Method, flexible direct current system provided in this embodiment are put by single valve group in above-mentioned flexible direct current system online
Single valve group puts into method online in system, when the transverter major loop troubleshooting or dielectric level of series connection recover, it is only necessary to will treat
It is in parallel with breaker and bypass isolating switch respectively to put into single valve group, can so make after input single valve group after breaking down, treat
Input single valve group is bypassed by bypass isolating switch, and operating current is made to be formed into a loop through bypass isolating switch, and it is entire to stop transport
Current conversion station；Then when putting into the single valve group, by disconnecting the bypass isolating switch in parallel with the i-th end single valve group to be put into, so
After unlock the i-th end single valve group to be put into, then disconnect the breaker in parallel with the i-th end single valve group to be put into, you can complete the i-th end and treat
Input single valve group puts into operation；Then the present embodiment is by keeping the i-th end to put into the direct current of single valve group place current conversion station
It presses constant, the input of i+1 end single valve group to be put into can be completed according to above-mentioned similary step, so as in the transverter master of series connection
When loop fault excludes, the transverter that rapidly will move out puts into operation online again.
It should be noted that bipolar or two kinds of methods of operation of monopole may be employed in the flexible direct current system in the present embodiment.
Specifically, the wiring diagram of the i-th end single valve group to be put into corresponding with above-mentioned steps S3 is as indicated with 2, at this point, with i-th
Hold the bypass isolating switch S of single valve group parallel connection to be put into1It disconnects, the breaker B in parallel with the i-th end single valve group to be put into1It is closed,
It so may be such that and flow through above-mentioned bypass isolating switch S1Electric current IsIt is transferred to breaker B1Form IB；It is corresponding with above-mentioned steps S5
The i-th end put into the wiring diagram of single valve group as shown in figure 3, at this point, the breaker B in parallel with the i-th end single valve group to be put into1It is disconnected
It opens, so that electric current flows through to form I through the i-th end single valve group to be put intoFM, the single valve group is made to put into operation；The present embodiment passes through bypass
The switching of disconnecting switch and breaker coordinates the input for realizing single valve group, this is because bypass isolating switch does not have special go out
Arc device, does not possess cutout abilities, so when putting into corresponding single valve group, the present embodiment is by being first closed with the single valve group simultaneously
The breaker of connection makes breaker that current path be collectively formed with bypass isolating switch, then disconnects bypass isolating switch, make electricity
Stream is only flowed through from breaker, so when finally putting into the single valve group, the breaker in parallel with the single valve group need to only be made to disconnect i.e.
It can.
It is understood that single valve group puts into the step S4 of method online in flexible direct current system provided in this embodiment
In, the i-th end single valve group to be put into is unlocked by zero DC voltage, the voltage that the i-th end single valve group to be put into is kept after unlock is zero,
Then it is transferred to step S5：By applying voltage △ U to the i-th end single valve group to be put into, generate the i-th end single valve group to be put into reversed
Electric current, the reverse current flow through the breaker in parallel with the i-th end single valve group to be put into, and the electric current for flowing through breaker generates zero passage
Point electric current is so that the breaker in parallel with the i-th end single valve group to be put into disconnects.
Specifically, as shown in Figure 1, further include step S2 between the step S1 of above-described embodiment and step S3：It is closed and i-th
The breaker of single valve group parallel connection to be put into is held, make the breaker in parallel with the i-th end single valve group to be put into and treats that input is single with the i-th end
The bypass isolating switch of valve group parallel connection forms current path, so can be at the i-th end when input single valve group breaks down stoppage in transit, electricity
Stream can be flowed through through breaker and bypass isolating switch connected in parallel, and the current conversion station where the single valve group that will not be broken down stops
Fortune.
It is understood that flexible direct current system provided in this embodiment includes determining direct current pressure side and determines active power
End, as shown in Figure 1, in step s 6, completing i+1 end after the input of input single valve group, further including：Step S7：It will be fixed straight
Galvanic electricity pressure side rises to rated voltage, active power end power per liter will be determined to rated power, to complete the input of multiterminal current conversion station fortune
Row.
In the description of the above embodiment, particular features, structures, materials, or characteristics can be in any one or more
It is combined in an appropriate manner in a embodiment or example.
The above description is merely a specific embodiment, but protection scope of the present invention is not limited thereto, any
Those familiar with the art in the technical scope disclosed by the present invention, can readily occur in change or replacement, should all contain
Lid is within protection scope of the present invention.Therefore, protection scope of the present invention should be based on the protection scope of the described claims.
Claims (6)
1. single valve group puts into method online in a kind of flexible direct current system, the flexible direct current system includes at least two changes of current
It stands, the two neighboring current conversion station is connected by DC power transmission line, and each current conversion station includes the valve group of series connection；Its feature
It is, single valve group puts into method and includes online in the flexible direct current system：
Step S1：I-th end single valve group to be put into is in parallel with breaker and bypass isolating switch respectively；
Step S3：The bypass isolating switch in parallel with the i-th end single valve group to be put into is disconnected, flows through the bypass isolating switch
Electric current is transferred to the breaker in parallel with the i-th end single valve group to be put into；
Step S4：The i-th end single valve group to be put into is unlocked, the voltage of the single valve group to be put into of the i-th end after unlock is made to remain zero；
Step S5：The breaker in parallel with the i-th end single valve group to be put into is disconnected, the i-th end single valve group to be put into is made to put into operation, it is complete
Into the input of the i-th end single valve group to be put into, obtain the i-th end and put into single valve group；
Step S6：It keeps the DC voltage that the i-th end has put into current conversion station where single valve group constant, repeats step S1-S5, complete the
The input of i+1 ends single valve group to be put into.
2. single valve group puts into method online in flexible direct current system according to claim 1, which is characterized in that the step
Step S2 is further included between S1 and the step S3：The breaker in parallel with the i-th end single valve group to be put into is closed, is made and the i-th end
The breaker of single valve group parallel connection to be put into and the bypass isolating switch in parallel with the i-th end single valve group to be put into form current path.
3. single valve group puts into method online in flexible direct current system according to claim 1, which is characterized in that the step
In S5, the method for disconnecting the breaker in parallel with the i-th end single valve group to be put into is：
Apply voltage △ U to i-th end single valve group to be put into, the i-th end single valve group to be put into is made to generate reverse current, it is described anti-
The breaker in parallel with the i-th end single valve group to be put into is flowed through to electric current, makes to generate zero crossing electric current on the breaker and disconnect.
4. single valve group puts into method online in flexible direct current system according to claim 1, which is characterized in that the flexibility
Straight-flow system includes determining direct current pressure side and determines active power end；In the step S6, i+1 end single valve group to be put into is completed
After input, further include：
Step S7：It will determine direct current pressure side and rise to rated voltage, active power end power per liter will be determined to rated power, change multiterminal
It puts into operation at stream station.
5. single valve group puts into method online in flexible direct current system according to claim 1, which is characterized in that the step
In S4, the method for unlock the i-th end single valve group to be put into is zero DC voltage unlock method.
6. single valve group puts into method online in flexible direct current system according to claim 1, which is characterized in that the flexibility
Transverter is modularization multi-level converter in straight-flow system, and the modularization multi-level converter Neutron module is full-bridge submodule
Block.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611043460.8A CN108092240A (en) | 2016-11-21 | 2016-11-21 | Single valve group puts into method online in a kind of flexible direct current system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611043460.8A CN108092240A (en) | 2016-11-21 | 2016-11-21 | Single valve group puts into method online in a kind of flexible direct current system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN108092240A true CN108092240A (en) | 2018-05-29 |
Family
ID=62170226
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201611043460.8A Pending CN108092240A (en) | 2016-11-21 | 2016-11-21 | Single valve group puts into method online in a kind of flexible direct current system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108092240A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110601249A (en) * | 2019-09-11 | 2019-12-20 | 南京南瑞继保电气有限公司 | Voltage source converter unit, online switching method and voltage source converter valve |
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| CN103762612A (en) * | 2013-11-27 | 2014-04-30 | 南方电网科学研究院有限责任公司 | Live access method for multi-terminal flexible direct current transmission system through disconnecting switch |
| CN104914746A (en) * | 2015-04-16 | 2015-09-16 | 北京荣信慧科科技有限公司 | MMC converter valve control device based on flexible DC power transmission and control method |
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2016
- 2016-11-21 CN CN201611043460.8A patent/CN108092240A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103762612A (en) * | 2013-11-27 | 2014-04-30 | 南方电网科学研究院有限责任公司 | Live access method for multi-terminal flexible direct current transmission system through disconnecting switch |
| CN104914746A (en) * | 2015-04-16 | 2015-09-16 | 北京荣信慧科科技有限公司 | MMC converter valve control device based on flexible DC power transmission and control method |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110601249A (en) * | 2019-09-11 | 2019-12-20 | 南京南瑞继保电气有限公司 | Voltage source converter unit, online switching method and voltage source converter valve |
| WO2021047460A1 (en) * | 2019-09-11 | 2021-03-18 | 南京南瑞继保电气有限公司 | Voltage source converter unit and online input method, and voltage source converter valve |
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