CN107749615A - It is a kind of tactful based on the dc circuit breaker for sealing in capacitor and its DC Line Fault processing - Google Patents
It is a kind of tactful based on the dc circuit breaker for sealing in capacitor and its DC Line Fault processing Download PDFInfo
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- CN107749615A CN107749615A CN201710909434.7A CN201710909434A CN107749615A CN 107749615 A CN107749615 A CN 107749615A CN 201710909434 A CN201710909434 A CN 201710909434A CN 107749615 A CN107749615 A CN 107749615A
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- circuit breaker
- switch
- submodule
- branch road
- series
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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
- H02H7/26—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
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Abstract
The invention discloses a kind of tactful based on the dc circuit breaker for sealing in capacitor and its DC Line Fault processing, including normal through-flow branch road, main transfer branch road, cutout branch road, reactor and disconnecting switch, normal through-flow branch route supper-fast mechanical switch and load-transfer switch and is composed in series, main transfer branch route main circuit breaker is formed, cutout branch route thyristor controlled series compensation and centralized capacitor are composed in series, load-transfer switch is made up of multiple submodule connection in series-parallel with two-way through-current capability, and main circuit breaker can be made up of multiple simple type half-bridge submodule connection in series-parallel.Breaker of the present invention changes fault current property using capacitor, and then fault current is blocked, and used IGBT negligible amounts, can substantially reduce construction costs and running wastage, have very strong reference significance and use value in engineering.
Description
Technical field
The invention belongs to power electronic system technical field, and in particular to a kind of based on the dc circuit breaker for sealing in capacitor
And its DC Line Fault processing strategy.
Background technology
Direct current network has two kinds of basic network forming modes：The first network forming mode uses the modularization based on half-bridge submodule
Multilevel converter (MMC) plus dc circuit breaker scheme, this network forming mode are applied to any more direct current network of end number；Second
Kind network forming mode uses the MMC with DC Line Fault self-cleaning ability, for example with the MMC based on full-bridge submodule, but need not
Dc circuit breaker, this network forming mode are applied to the small-scale direct current network that end number is less than 10.Added directly using half-bridge submodule MMC
When flowing the network forming mode of breaker, usually require that current conversion station continues to run with during DC line fault, it is impossible to locking, faulty line
Quickly cut off by dc circuit breaker, its troubleshooting principle is similar with AC network.Using the network forming mode without dc circuit breaker
When, related converter blocking in net during DC line fault, 10ms or so fault currents to zero and are stable at null value after locking,
Again by disconnecting switch isolated fault circuit, then related converter deblocking recovers power transmission again, to recovering to send since failure
The time of electricity, generally the impact to AC network was within the scope of it can bear typically in 20ms or so.
When adding the network forming mode of dc circuit breaker using half-bridge submodule MMC, dc circuit breaker just turns into direct current network
Key element.High voltage DC breaker structural scheme focuses primarily upon 3 types at present, is based on ordinary tap respectively
Tradition machinery type breaker, the solid circuit breaker based on pure power electronic devices and the hybrid circuit-breaker based on the two combination.
Although having developed technically feasible high voltage DC breaker at present, its is with high costs, bulky, it is difficult to disconnected as exchanging
Road device widely uses in power network like that.Therefore, dc circuit breaker is still the essence technical bottleneck for developing direct current network.
The content of the invention
In view of it is above-mentioned, plan is handled based on the dc circuit breaker for sealing in capacitor and its DC Line Fault the invention provides a kind of
Slightly, the breaker changes fault current property using capacitor, and then fault current is blocked, and used IGBT quantity
It is less, construction costs and running wastage can be substantially reduced, there is very strong reference significance and use value in engineering.
It is a kind of based on the dc circuit breaker for sealing in capacitor, including normal through-flow branch road, main transfer branch road, cutout branch road,
Reactor and disconnecting switch, normal through-flow branch road and one end after main transfer branch road and the branch circuit parallel connection that stops and disconnecting switch
One end is connected, and the other end is connected with DC power transmission line, and the other end of disconnecting switch is connected with one end of reactor, reactor
The other end is connected with current conversion station；The normal through-flow branch route supper-fast mechanical switch and load-transfer switch and is composed in series, institute
State main transfer branch route main circuit breaker to form, the cutout branch route thyristor controlled series compensation and centralized capacitor are composed in series, institute
State main circuit breaker to be made up of multiple submodule connection in series-parallel, the load-transfer switch is by multiple submodules with two-way through-current capability
Block connection in series-parallel is formed, and the thyristor controlled series compensation is made up of multiple IGCT connection in series-parallel.
Further, the submodule of the main circuit breaker is using full-bridge sub-modular structure, enhanced half-bridge sub-modular structure
Or simple type half-bridge sub-modular structure.
Further, the submodule of the load-transfer switch uses full-bridge sub-modular structure or enhanced half-bridge submodule
Structure.
Further, the enhanced half-bridge sub-modular structure include two IGBT pipes T1 with anti-paralleled diode~
T2, two diode D1~D2 and an electric capacity C1；Wherein, IGBT pipes T1 emitter stage is connected simultaneously with diode D1 negative electrode
As one end of submodule, IGBT pipes T1 colelctor electrode is connected with IGBT pipes T2 colelctor electrode and electric capacity C1 one end, IGBT
Pipe T2 emitter stage is connected with diode D2 negative electrode and is used as the other end of submodule, diode D1 anode and diode D2
Anode and the electric capacity C1 other end be connected, IGBT pipes T1~T2 base stage connects the switch control of external control circuit offer
Signal.
Further, the simple type half-bridge sub-modular structure includes an electric capacity C2, an IGBT pipes T3 and one
Diode D3；Wherein, IGBT pipes T3 colelctor electrode is connected with electric capacity C2 one end and is used as one end of submodule, and electric capacity C2's is another
One end is connected with diode D3 anode, and diode D3 negative electrode is connected with IGBT pipes T3 emitter stage and is used as the another of submodule
One end, IGBT pipes T3 base stage connect the switch controlling signal of external control circuit offer.
The DC Line Fault processing strategy of the dc circuit breaker, comprises the following steps：
(1) during normal operation, close disconnecting switch and supper-fast mechanical switch, all submodules in load-transfer switch
All submodules are off state in opening state, main circuit breaker, and all IGCTs are off in thyristor controlled series compensation
State, then DC current flowed through from normal through-flow branch road；
(2) DC power transmission line occurs under ground fault condition, after fault current is detected, in load-transfer switch
All submodules apply cut-off signals, while apply open signal to all submodules in main circuit breaker；
(3) pass through a bit of delay, disconnect supper-fast mechanical switch；Treat that supper-fast mechanical switch is completely in off state
Afterwards, all IGCTs in thyristor controlled series compensation are arranged to opening state；
(4) all submodules in main circuit breaker are arranged to off state, block fault current to lead to through a bit of delay again
Road.
Compared with prior art, the present invention has following advantageous effects：
1. during steady-state operation, DC current flows through normal through-flow branch road, due to the load-transfer switch submodule of the present invention
Quantity is seldom, therefore steady-state operation loss is low.
2. because the main circuit breaker submodule of the present invention can use simple type half-bridge submodule, therefore device count used
Amount can greatly reduce, and the cost of investment of breaker is greatly lowered.
3. it can be chosen due to the submodule capacitance present invention employs centralized capacitor, therefore in main circuit breaker
Very little, This further reduces the cost of investment of breaker.
Brief description of the drawings
Fig. 1 is the topological structure schematic diagram of dc circuit breaker of the present invention.
Fig. 2 (a) is the topological structure schematic diagram of full-bridge submodule.
Fig. 2 (b) is the topological structure schematic diagram of enhanced half-bridge submodule.
Fig. 2 (c) is the topological structure schematic diagram of simple type half-bridge submodule.
Fig. 3 is the simulation waveform schematic diagram of dc circuit breaker of the present invention.
Embodiment
In order to more specifically describe the present invention, below in conjunction with the accompanying drawings and embodiment is to technical scheme
It is described in detail.
As shown in figure 1, the present invention includes normal through-flow branch road, main transfer branch based on the dc circuit breaker for sealing in capacitor
Road, cutout branch road, reactor and disconnecting switch, wherein：Normal through-flow branch road, main transfer branch road are in parallel with cutout branch road three
Connection, one end after being connected in parallel are connected with DC line, and the other end is connected with one end of disconnecting switch；Disconnecting switch it is another
End is connected with one end of reactor；The other end of reactor is connected with current conversion station.
Normal through-flow branch road includes supper-fast mechanical switch and load-transfer switch, wherein supper-fast mechanical switch and load
Transfer switch is cascaded；Main transfer branch road includes main circuit breaker, and cutout branch road includes thyristor controlled series compensation and centralized electric capacity
Device is connected, and thyristor controlled series compensation is made up of multiple IGCT connection in series-parallel.Load-transfer switch is by several submodules SM1 connection in series-parallel structures
Into main circuit breaker is made up of many submodule SM2 connection in series-parallel.Submodule SM1 has two-way through-current capability, and its structure has a lot
Kind, including full-bridge sub-modular structure, enhanced half-bridge sub-modular structure etc.；Submodule SM2 structure has many kinds, including full-bridge
Sub-modular structure, enhanced half-bridge sub-modular structure and simple type half-bridge sub-modular structure etc..
Normal through-flow branch road and main transfer branch road are consistent with the function of mixed type dc circuit breaker in the present invention, and stop branch road
It is in series by thyristor valve and centralized capacitor；DC current flows through from normal through-flow branch road during normal operation, stops
Without flow through electric current in branch road.The submodule of load-transfer switch is needed using the submodule with two-way through-current capability, and main disconnected
Submodule in the device of road can have many types, full-bridge submodule that Fig. 2 (a)~Fig. 2 (c) is respectively shown in, enhanced half-bridge
Module and simple type half-bridge submodule are three kinds of feasible schemes.It should be noted that branch road is stopped during due to steady-state operation not
Electric current is flowed through, and the current polarity for occurring to flow through main circuit breaker during DC Line Fault is single, so the submodule in main circuit breaker
Block can use relatively inexpensive simple type half-bridge submodule.
Simple type half-bridge submodule is divided into conducting state and off state：When IGBT is opened, electric current flows through from IGBT, electricity
Appearance is bypassed, and is designated as conducting state；When IGBT is turned off, electric current flows through from capacitive branch, is designated as off state.
The DC Line Fault processing strategy of dc circuit breaker of the present invention includes：
(1) before failure occurs, disconnecting switch closure, supper-fast mechanical switch closure, all submodules of load-transfer switch
In the conduction state, all submodules of main circuit breaker are off, and all IGCTs of thyristor controlled series compensation are off,
DC current flows through from normal circulation branch road；
(2) after DC Line Fault is detected, all submodules of load-transfer switch are arranged to off state, simultaneously will
All submodules of main circuit breaker are arranged to conducting state；
(3) pass through a bit of delay, open supper-fast mechanical switch；
(4) after supper-fast mechanical switch is completely in off state, conducting thyristor valve group；
(5) pass through a bit of delay, all submodules of main circuit breaker are arranged to off state, block fault current to lead to
Road.
Simulating, verifying is carried out using single-ended 400kV, 400MW test system below, dc circuit breaker is using as shown in Figure 1
Breaker, wherein load-transfer switch uses enhanced half-bridge submodule, and main circuit breaker uses simple type half-bridge submodule, main
Breaker equivalent capacitance value is 10 μ F, and centralized capacitance is 100 μ F.
Exported if (t=0ms) test system has been enter into steady-state operation when emulation starts, during t=10ms in smoothing reactor
Monopole ground short circuit occurs for place, and load-transfer switch adds shut-off to instruct during t=13ms, during t=13.1ms high speed machine switch plus
Open command, high speed machine switch is opened completely during t=15ms, while triggers the thyristor valve in cutout branch road, t=15.1ms
When it is main transfer branch road add shut-off instruct.Fig. 3 give normal through-flow branch current, main transfer branch current, cutout branch current,
The main change curve for shifting branch voltage, thyristor valve voltage, centralized condenser voltage and MMC DC voltages.
From figure 3, it can be seen that after to main transfer branch road application shut-off instruction, electric current flows through main transfer branch road and broken simultaneously
Flow branch road.Because the centralized capacitance for the branch road that stops is far longer than main circuit breaker equivalent capacitance value, therefore electric current is mainly from disconnected
Stream branch road flows through.It can also be seen that can quickly separate DC current based on the dc circuit breaker for sealing in capacitor from Fig. 3,
And the overvoltage in fault treating procedure is controlled within 600kV, illustrates that breaker has good cutout characteristic.
The above-mentioned description to embodiment is understood that for ease of those skilled in the art and using the present invention.
Person skilled in the art obviously can easily make various modifications to above-described embodiment, and described herein general
Principle is applied in other embodiment without by performing creative labour.Therefore, the invention is not restricted to above-described embodiment, ability
For field technique personnel according to the announcement of the present invention, the improvement made for the present invention and modification all should be in protection scope of the present invention
Within.
Claims (6)
- It is 1. a kind of based on the dc circuit breaker for sealing in capacitor, it is characterised in that：Including normal through-flow branch road, main transfer branch road, Stop branch road, reactor and disconnecting switch, normal through-flow branch road and one end after main transfer branch road and cutout branch circuit parallel connection with One end of disconnecting switch is connected, and the other end is connected with DC power transmission line, the other end of disconnecting switch and one end phase of reactor Even, the other end of reactor is connected with current conversion station；The normal through-flow branch route supper-fast mechanical switch and load-transfer switch It is composed in series, the main transfer branch route main circuit breaker is formed, the cutout branch route thyristor controlled series compensation and centralized capacitor It is composed in series, the main circuit breaker is made up of multiple submodule connection in series-parallel, and the load-transfer switch has two-way by multiple The submodule connection in series-parallel composition of stream ability, the thyristor controlled series compensation are made up of multiple IGCT connection in series-parallel.
- 2. dc circuit breaker according to claim 1, it is characterised in that：The submodule of the main circuit breaker is using full-bridge Modular structure, enhanced half-bridge sub-modular structure or simple type half-bridge sub-modular structure.
- 3. dc circuit breaker according to claim 1, it is characterised in that：The submodule of the load-transfer switch is using complete Bridge sub-modular structure or enhanced half-bridge sub-modular structure.
- 4. the dc circuit breaker according to Claims 2 or 3, it is characterised in that：The enhanced half-bridge sub-modular structure bag Include two IGBT pipes T1~T2 with anti-paralleled diode, two diode D1~D2 and an electric capacity C1；Wherein, IGBT is managed T1 emitter stage is connected with diode D1 negative electrode and is used as one end of submodule, and IGBT pipes T1 colelctor electrode is with IGBT pipes T2's Colelctor electrode and electric capacity C1 one end are connected, and IGBT pipes T2 emitter stage is connected with diode D2 negative electrode and is used as submodule The other end, diode D1 anode are connected with the other end of diode D2 anode and electric capacity C1, IGBT pipes T1~T2 base The switch controlling signal of external control circuit offer is extremely provided.
- 5. dc circuit breaker according to claim 2, it is characterised in that：The simple type half-bridge sub-modular structure includes one Individual electric capacity C2, an IGBT pipes T3 and a diode D3；Wherein, IGBT pipes T3 colelctor electrode is connected with electric capacity C2 one end And be connected as one end of submodule, the electric capacity C2 other end with diode D3 anode, diode D3 negative electrode and IGBT are managed T3 emitter stage is connected and is used as the other end of submodule, and IGBT pipes T3 base stage connects the switch control of external control circuit offer Signal.
- 6. the DC Line Fault processing strategy of dc circuit breaker as described in Claims 1 to 5 any claim, including following step Suddenly：(1) during normal operation, close disconnecting switch and supper-fast mechanical switch, all submodules are in load-transfer switch Opening state, all submodules are off state in main circuit breaker, and all IGCTs are off state in thyristor controlled series compensation, Then DC current flows through from normal through-flow branch road；(2) DC power transmission line occurs under ground fault condition, after fault current is detected, to owning in load-transfer switch Submodule applies cut-off signals, while applies open signal to all submodules in main circuit breaker；(3) pass through a bit of delay, disconnect supper-fast mechanical switch；After supper-fast mechanical switch is completely in off state, All IGCTs in thyristor controlled series compensation are arranged to opening state；(4) all submodules in main circuit breaker are arranged to off state, block fault current path through a bit of delay again.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710909434.7A CN107749615B (en) | 2017-09-29 | 2017-09-29 | It is a kind of based on the dc circuit breaker for sealing in capacitor and its DC Line Fault processing strategie |
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|---|---|---|---|
| CN201710909434.7A CN107749615B (en) | 2017-09-29 | 2017-09-29 | It is a kind of based on the dc circuit breaker for sealing in capacitor and its DC Line Fault processing strategie |
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| CN107749615B CN107749615B (en) | 2019-01-04 |
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Cited By (4)
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| CN109066606A (en) * | 2018-07-12 | 2018-12-21 | 武汉杭久电气有限公司 | A kind of two-way forced commutation type direct current current-limiting circuit breaker |
| CN109768528A (en) * | 2019-01-24 | 2019-05-17 | 浙江大学 | A kind of mechanical switch dc circuit breaker and its troubleshooting strategy based on series capacitor |
| CN110994567A (en) * | 2019-12-10 | 2020-04-10 | 国网江苏省电力有限公司电力科学研究院 | Direct current power grid fault current controller |
| CN112803758A (en) * | 2021-01-15 | 2021-05-14 | 西安交通大学 | Non-isolated high-voltage direct current-direct current converter with fault blocking function and method |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109066606A (en) * | 2018-07-12 | 2018-12-21 | 武汉杭久电气有限公司 | A kind of two-way forced commutation type direct current current-limiting circuit breaker |
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| CN112803758B (en) * | 2021-01-15 | 2021-12-28 | 西安交通大学 | Non-isolated high-voltage direct current-direct current converter with fault blocking function and method |
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| CN107749615B (en) | 2019-01-04 |
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