CN104767218B - Direct-current power flow controller - Google Patents
Direct-current power flow controller Download PDFInfo
- Publication number
- CN104767218B CN104767218B CN201510179145.7A CN201510179145A CN104767218B CN 104767218 B CN104767218 B CN 104767218B CN 201510179145 A CN201510179145 A CN 201510179145A CN 104767218 B CN104767218 B CN 104767218B
- Authority
- CN
- China
- Prior art keywords
- power
- current
- transmission line
- direct
- output
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- 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]
Abstract
The invention discloses a direct-current power flow controller which is suitable for multi-port direct-current transmission systems. The controller comprises two converters. The output ends of the converters are connected to different transmission lines in series. Each converter can output or absorb power in a direct-current mode and can also output or absorb power in an alternating-current mode at the same time. A band-pass filter between the two converters can limit power formed by alternating-current voltage and alternating current in an auxiliary passageway, and the alternating-current component on a direct-current transmission line can be effectively restrained. In this way, decoupling control over the power in a direct-current power ring and the power in an alternating-current power ring can be achieved, the direct-current power ring is specially used for power flow control over the direct-current transmission line, and the alternating-current power ring is used for power balance of the converters. According to the direct-current power flow controller, the structure of a circuit is simple, the number of switch devices is small, and a low-frequency isolation transformer and an external power source are not needed.
Description
Technical field
The present invention relates to a kind of Novel DC flow controller based on quadrature power decoupling, belong to Power Electronic Technique neck
Domain, is mainly used in direct current transportation occasion.
Background technology
Multi-terminal direct current transmission system is by 3 and above current conversion station, is coupled together by series, parallel or series-parallel connection mode
DC transmission system, it is capable of multiple feed and many drop points are subject to electricity, compared to two ends HVDC transmission system fortune
Row is more economical flexibly, is that the extensive regenerative resource that solution China faces at present is grid-connected, the remote electrical energy transportation of Large Copacity
One of effective technology means the problems such as in short supply with transmission of electricity corridor.Compared to conventional current source type inverter, voltage source converter
(voltage source converter, vsc) DC current direction when trend inverts inverts and DC voltage is constant, and does not have
The problems such as have commutation failure, thus be conducive to constituting Multi-end flexible direct current transmission (vsc based multi-terminal high
Voltage direct current, vsc-mtdc) system.Typical looped network formula three end vsc-mtdc system equivalent circuit is as schemed
It is assumed that vsc1 and vsc2 is the current conversion station of two marine wind electric fields respectively shown in 10, run for determining power mode, vsc3 is on the bank
Current conversion station, for determining DC voltage mode operation, power transmits to vsc3 from vsc1 and vsc2.In order to adjust on DC transmission line
Trend, needs to seal in DC power flow controller in power transmission line.Due to there is not reactive power, reactance and the phase angle of alternating current,
Vsc-mtdc system can only adjust transmission line of electricity resistance and DC voltage to control DC power flow.
Controlling transmission line of electricity resistance, typically sealing in variable resistance in transmission line of electricity to control DC power flow.
The advantage sealing in variable resistance scheme in transmission line of electricity is structure and controls simple, its shortcoming is it is also obvious that be such as lost big, to dress
Put radiating and propose very high request, and transmission line of electricity equivalent resistance can only be increased, the unidirectional regulation of trend.
In terms of controlling DC voltage, scholar is had to propose scheme using dc/dc transformator, the advantage of the program is can
For connecting the straight-flow system of different electric pressures, to improve the operational flexibility of DC transmission system, no-load voltage ratio can be also 1
The dc/dc transformator of left and right seals in the straight-flow system of same electric pressure, adjusts straight-flow system trend by finely tuning no-load voltage ratio,
Deficiency is that all of power is required for, by dc/dc transformator, being lost larger.Another scheme is that seal in transmission line of electricity can
Voltage source is adjusted to change DC voltage and then to control DC power flow.Professor b.-t.ooi as Canadian McGill University etc. proposes
A kind of adjustable voltage source circuit structure (veilleux e, the ooi b.multiterminal hvdc based on thyristor control
With thyristor power-flow controller.ieee transactions on power delivery,
2012,27 (3): 1205-1212) and senior engineer Li Yalou etc. of China Electric Power Research Institute proposes a kind of ac/dc+dc/
Dc two-stage type adjustable voltage source circuit structure (mu q, liang j, li y, zhou x.power flow control
devices in dc grids.ieee power and energy society general meeting,2012:1-7).
Compared to dc/dc transformator, the power and the corresponding loss that seal in variable voltage source are all little, and electric pressure is low, is more easy to realize.But this
The circuit structure planting two schemes needs an external power source to provide power for variable voltage source or absorb its power, also needs low
Frequency high voltage isolating transformer carries out voltage isolation, and required switching device is more.
Content of the invention
Technical problem: the present invention is directed to the technical requirements that in multi-terminal direct current transmission system, DC power flow controls, proposes a kind of
Based on the DC power flow controller of quadrature power decoupling, this controller does not need the straight of low frequency isolation transformator and external power source
Stream power flowcontrol mode, be can achieve the effective control of trend, improves power transmission network trend side by simple control method
To control ability and transmission line of electricity conveying capacity.
Technical scheme: a kind of DC power flow controller it is adaptable to multi-terminal HVDC transmission network, including two changers and one
Individual band filter；
The output of described two changers is connected on certain current conversion station any two of multi-terminal HVDC transmission network not respectively
With transmission line of electricity in, described band filter is series between the output of two changers so that the output of two changers,
Form a secondary ring between band filter and current conversion station；
Each changer, while with a direct current output or absorbed power, can exchange absorption or send power；?
The power limit that alternating voltage on DC power transmission line, alternating current can be formed by the band filter between two changers
Make in auxiliary channel, the AC compounent on suppression DC power transmission line；Realize power in dc power ring and AC power ring
Uneoupled control, make dc power ring dedicated for the power flowcontrol on DC transmission line, AC power ring is used for changer
Power-balance.
Further, described changer includes h bridge, is connected to input capacitance c of h bridge inputinExport with being connected to h bridge
The lc filter circuit at end, described lc filter circuit includes inductance and output capacitance c connectedout, described output capacitance coutSeries connection
In transmission line of electricity.When the dc power of h bridge is balanced each other with AC power, input capacitance cinVoltage just can stable in setting
Value.And in c during flow controller workoutThe middle of ac that can produce a DC quantity and a fixed frequency, DC quantity participates in
Power flow regulating, of ac is used for balancing the power of h bridge.Dc power on h bridge and AC power are separate, are independent of each other
, the dc power on h bridge during stable state is balanced each other with AC power, and h bridge is without external power source.
Further, described band filter is made up of lc series resonant circuit, and one end connects a changer output electricity
Hold coutPositive pole, one end connect another changer output capacitance coutNegative pole, the resonant frequency of band filter is auxiliary
The frequency of AC power ring in loop.
Beneficial effect: the DC power flow controller of the present invention is applied to multi-terminal HVDC transmission occasion, with traditional direct current tide
Stream controller is compared, the DC power flow device circuit structure of the present invention is simple, switching device is few, without low frequency isolation transformator and
External power source, be can achieve the effective control of trend, improves the control of power transmission network direction of tide by simple control method
Ability processed and transmission line of electricity conveying capacity.
Brief description
Fig. 1 is the looped network formula three end DC transmission system of the DC power flow controller comprising the present invention；
Fig. 2 is the looped network formula three end DC transmission system equivalent circuit of the DC power flow controller comprising the present invention；
Fig. 3 is the equivalent circuit of variable voltage source DC component；
Fig. 4 is the equivalent circuit of variable voltage source AC compounent；
Fig. 5 is the circuit topology of variable voltage source；
Fig. 6 is the current waveform that flow controller is not involved in transmission line of electricity during work；
Fig. 7 is the current waveform of transmission line of electricity during flow controller participation work；
Fig. 8 is the voltage waveform that during flow controller participation work, h bridge inputs lateral capacitance；
Fig. 9 is the voltage waveform that during flow controller participation work, h bridge exports lateral capacitance；
Figure 10 is typical looped network formula three end vsc-mtdc system equivalent circuit.
Specific embodiment
The present invention is further illustrated below in conjunction with the accompanying drawings.
The present invention is suitable for multiterminal (more than three ends and three ends) HVDC transmission system, below only with three end DC power transmission systems
It is described in detail as a example system.
The three end DC transmission systems comprising DC power flow controller of the present invention are as shown in figure 1, vsc3 is to determine DC voltage
Mode operation, vsc1 and vsc2 is to determine power mode to run, and DC power flow control program includes two changers, and changer is installed
In rotary substation vsc2, the output (v of changerxAnd vy) be connected on respectively in two transmission lines of electricity at vsc2.Comprise the present invention
Three end DC transmission system equivalent circuits of DC power flow control mode are as shown in Figure 2.Changer one and changer two are all simultaneously
Produce DC voltage (vxd, vyd) and alternating voltage (vxac, vyac).It is h bridge circuit from changer, h bridge is by switching s1-s4 structure
Become, s1 is in parallel with the series arm of s2 and the series arm of s3 and s4.The input side of h bridge is electric capacity cin, the outlet side employing of h bridge
Lc filters, wherein electric capacity coutIt is connected in transmission line of electricity, in c during flow controller workoutIn can produce a DC quantity and
The of ac of one fixed frequency, for reducing flow range on DC transmission line for the of ac, increased lc bypass link.When
When the dc power of h bridge and AC power balance each other, input capacitance cinVoltage just can be stabilized.If power pxacFor voltage source
vxThe AC power sending, pxdFor voltage source vxThe dc power sending, pyacFor voltage source vyThe AC power sending, pydFor
Voltage source vyThe dc power sending then has:
pxac+pxd=0
pyac+pyd=0
Variable voltage source need not outwardly transmit energy, and energy is transmitted between two variable voltage sources by power transmission line,
Then the dc power that voltage source sends and AC power can be fully absorbed by another voltage source, then to ignore line loss
Have:
pxac+pyac=0
pxd+pyd=0
As shown in figure 4, DC quantity transmits energy by whole DC transmission line, for adjusting DC power flow.By inciting somebody to action
The resonant frequency of ls and cs designs under the frequency of variable voltage source alternating voltage, of ac can be made to pass through extremely short direct current defeated
Electric wire, the very big A.C.power loss that must decrease on power transmission line.The of ac of variable voltage source is served only for the power self-balancing of h bridge,
The power flowcontrol of DC transmission line is not contributed.
The present invention can be used for controlling on DC transmission line based on the Novel DC flow controller of quadrature power decoupling
The electric current of certain circuit, to analyze the control to DC transmission line trend for the DC controller with a specific simulation example below
Effect.Emulation using three end ring net formula flexible direct current power transmission system shown in Fig. 1, vsc3 for determining DC voltage mode operation,
Control v3=1000v, vsc1 and vsc2 are to determine power mode to run, and inject p to system respectively1=50kw and p2=100kw work(
Rate, the parameter of three sections of transmission lines of electricity is as shown in table 1.
The line parameter circuit value of the three-terminal flexible direct-current power transmission system shown in table 1 Fig. 1
| Transmission line parameter | line1 | line2 | line3 |
| Resistance/ω | 0.2 | 0.1 | 0.3 |
| Inductance/mh | 0.2 | 0.1 | 0.3 |
Current waveform on DC transmission line when DC power flow actuator does not work is as shown in fig. 6, the now electricity on circuit 1
Flow for 40a.Assume that now circuit 1 needs fall electric current to operate in 30a (i12=30), the electricity on power transmission line after input flow controller
Stream waveform is as shown in fig. 7, i12Effect for 30a and due to lc series resonant circuit, the electric current on DC line only exists direct current
Amount.After steady operation, flow controller itself has reached the balance of dc power and AC power, the capacitance voltage of its input side
Waveform is as shown in figure 8, voltage stabilization is in 20v.Fig. 9 is the voltage waveform in flow controller output capacitance during stable state, electric capacity electricity
Pressure is DC quantity and the superposition of of ac.
The preferred embodiment of the present invention described in detail above, but, the present invention is not limited in above-mentioned embodiment
Detail, in the range of the technology design of the present invention, multiple equivalents can be carried out to technical scheme, this
A little equivalents belong to protection scope of the present invention.
Claims (3)
1. a kind of DC power flow controller it is adaptable to multi-terminal HVDC transmission network it is characterised in that: include two changers and
Individual band filter；
Certain current conversion station any two that the output of described two changers is connected on multi-terminal HVDC transmission network respectively is different
In transmission line of electricity, described band filter is series between the output of two changers so that the output of two changers, band logical
Form a secondary ring between wave filter and current conversion station；
Each changer, while with a direct current output or absorbed power, can exchange absorption or send power；At two
The Power Limitation that alternating voltage on DC power transmission line, alternating current can be formed by the band filter between changer exists
AC compounent in auxiliary channel, on suppression DC power transmission line；Realize the solution of power in dc power ring and AC power ring
Coupling controls, and makes dc power ring dedicated for the power flowcontrol on DC transmission line, AC power ring is used for the power of changer
Balance.
2. a kind of DC power flow controller according to claim 1 it is characterised in that: described changer includes h bridge, connection
Input capacitance c in h bridge inputinWith the lc filter circuit being connected to h bridge outfan, described lc filter circuit include connect
Inductance and output capacitance cout, described output capacitance coutIt is connected in transmission line of electricity.
3. a kind of DC power flow controller according to claim 2 it is characterised in that: described band filter is connected by lc
Resonance circuit is constituted, and one end connects changer output capacitance coutPositive pole, one end connect another changer output capacitance
coutNegative pole.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510179145.7A CN104767218B (en) | 2015-04-15 | 2015-04-15 | Direct-current power flow controller |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510179145.7A CN104767218B (en) | 2015-04-15 | 2015-04-15 | Direct-current power flow controller |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104767218A CN104767218A (en) | 2015-07-08 |
| CN104767218B true CN104767218B (en) | 2017-01-25 |
Family
ID=53648912
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510179145.7A Active CN104767218B (en) | 2015-04-15 | 2015-04-15 | Direct-current power flow controller |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104767218B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105162109B (en) * | 2015-08-21 | 2017-08-04 | 东南大学 | DC power flow controller optimization collocation method based on sensitivity analysis |
| CN108321785A (en) * | 2018-01-30 | 2018-07-24 | 南京理工大学 | Commonly connected capacitance values choosing method in DC power flow controller |
| CN108761304B (en) * | 2018-04-03 | 2020-08-25 | 国家电网有限公司 | Parameter setting method and device of dynamic energy leakage device and simulation equipment |
| CN110350566B (en) * | 2019-06-04 | 2020-12-29 | 上海交通大学 | Three-terminal direct current system containing direct current power flow controller |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104184139B (en) * | 2014-09-12 | 2016-03-30 | 东南大学 | For DC power flow controller and the control method of Multi-end flexible direct current transmission system |
-
2015
- 2015-04-15 CN CN201510179145.7A patent/CN104767218B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN104767218A (en) | 2015-07-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2017152720A1 (en) | Method and apparatus for controlling hybrid direct-current transmission system | |
| CN103516230B (en) | Many level that bi-directional current controls balance solid-state transformer and its implementation mutually | |
| CN104377720B (en) | A kind of direct current transportation flow control method based on MMC rotary substation | |
| CN104184139B (en) | For DC power flow controller and the control method of Multi-end flexible direct current transmission system | |
| CN105490552A (en) | Modular multilevel converter (MMC) based solid-state transformer and control method thereof | |
| US10181799B2 (en) | Hybrid back-to-back direct current transmission system and power flow reversal control method | |
| CN104767218B (en) | Direct-current power flow controller | |
| CN103001242A (en) | HVDC (high voltage direct current controller) and UPFC (unified power flow controller) system based on modularized multi-level converter | |
| CN107994584A (en) | A kind of major loop wiring construction of compensator | |
| CN108923429B (en) | In-phase power supply substation | |
| CN103107725A (en) | Multi-level converter with direct current voltage reverse function | |
| CN104734134A (en) | Inverter grounding system | |
| CN104065063A (en) | Unified power flow controller suitable for multiple lines | |
| CN107153152A (en) | A kind of grid adaptability test device | |
| CN206908254U (en) | Intensive deicing device constant current, constant pressure modularization dynamic passive compensation part | |
| CN106130020B (en) | Series compensation device suitable for double-circuit line | |
| CN104767191B (en) | A kind of inverter earthed system | |
| CN103384119A (en) | Alternating current side energy-taking device and method for static var generator unit module | |
| CN107171270B (en) | Intensive deicing device constant current, constant pressure modularization dynamic passive compensation component | |
| CN103236693A (en) | Unified electric energy quality controller | |
| CN206945888U (en) | A kind of grid adaptability test device | |
| CN102201744A (en) | Double-chain type high-voltage frequency converter | |
| CN106159975B (en) | Series compensation device suitable for multi-circuit line | |
| CN104092224A (en) | Convertible static synchronous compensator | |
| CN204464987U (en) | A kind of converter grounding system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| EXSB | Decision made by sipo to initiate substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |