CN103904677B - The method for handover control of a kind of VSC-HVDC between networking and decoupled mode - Google Patents

The method for handover control of a kind of VSC-HVDC between networking and decoupled mode Download PDF

Info

Publication number
CN103904677B
CN103904677B CN201410120088.0A CN201410120088A CN103904677B CN 103904677 B CN103904677 B CN 103904677B CN 201410120088 A CN201410120088 A CN 201410120088A CN 103904677 B CN103904677 B CN 103904677B
Authority
CN
China
Prior art keywords
vsc
control
receiving end
end vsc
alternating voltage
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.)
Expired - Fee Related
Application number
CN201410120088.0A
Other languages
Chinese (zh)
Other versions
CN103904677A (en
Inventor
徐政
刘昇
唐庚
宋鹏程
于洋
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Zhejiang University ZJU
Original Assignee
Zhejiang University ZJU
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Zhejiang University ZJU filed Critical Zhejiang University ZJU
Priority to CN201410120088.0A priority Critical patent/CN103904677B/en
Publication of CN103904677A publication Critical patent/CN103904677A/en
Application granted granted Critical
Publication of CN103904677B publication Critical patent/CN103904677B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

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]

Landscapes

  • Inverter Devices (AREA)

Abstract

The invention discloses the method for handover control of a kind of VSC-HVDC between networking and decoupled mode, the method judges the control model that VSC is current and residing operational mode by the local electrical quantities and control signal detecting VSC, when finding that VSC present control mode does not mate with the operational mode residing for VSC, the control model of VSC is switched fast.Therefore the inventive method makes VSC precisely can net side active power and reactive power by control VSC when networking operation mode, simultaneously, enable VSC when decoupled mode for passive isolated island provides stable and the voltage waveform of high-quality, therefore, the method for VSC-HVDC conversion mutually between networking operation mode and decoupled mode can ensure that VSC-HVDC stably switches between two kinds of operational modes.

Description

The method for handover control of a kind of VSC-HVDC between networking and decoupled mode
Technical field
The invention belongs to technical field of power systems, be specifically related to the method for handover control of a kind of VSC-HVDC between networking and decoupled mode.
Background technology
VSC-HVDC(voltage source converter based high voltage direct current, voltage source converter type DC transmission system) adopt and can turn off power electronic device, without the need to just commutation being realized by external power source, therefore possesses the ability of powering to passive network.In addition, VSC-HVDC technology is compared with Traditional DC technology of transmission of electricity, also have do not need reactive power compensation, low without commutation failure problem, harmonics level, be applicable to forming the technical advantages such as multi-terminal direct current transmission system, floor space are little, therefore VSC-HVDC has wide future in engineering applications.
In operation of power networks, for strengthening the power supply reliability of important load, VSC-HVDC and alternating current circuit can be adopted to be that important load supplies power with double circuit, to supply power with double circuit under normal circumstances, in particular cases by VSC-HVDC or alternating current circuit single service.The Zhoushan Multi-end flexible direct current transmission engineering of building for China, this project is when normally running, five VSC(voltage source converter, voltage source converter) all there is alternating current circuit to contact (this operational mode is called networking operation mode) with AC network, but under fault or maintenance situation, passive isolated island will be there is in the electrical network of Zhoushan, therefore need certain or certain several VSC to passive island with power (this operational mode is called decoupled mode), but VSC isolated island mode is interim operational mode, after alternating current interconnection fault clearance or maintenance complete, for strengthening system power supply reliability, passive isolated island still needs to be connected with the recovery of AC network by alternating current circuit reclosing, VSC proceeds to networking operation mode thereupon.Under above-mentioned situation, VSC needs to possess the ability of stable conversion between networking operation mode and decoupled mode.
The control strategy that VSC-HVDC is connected with origin system mainly contains constant DC voltage control, determines active power controller, determines alternating voltage control, determines Reactive Power Control, determines the modes such as FREQUENCY CONTROL.The control strategy that VSC-HVDC powers to passive network mainly comprises the modes such as width phase control, direct voltage control, Direct Current Control and nonlinear Control.Zhang L, Harnefors L, Nee H P is Modeling and controlof VSC-HVDC links connected to island systems(IEEE Transactions on PowerSystems at title, 2011, 26 (2): 783-793) point out in document that VSC exists stability of control system and dynamic property poor problem when adopting constant dc power control mode to be connected with weak AC system, and propose a kind of VSC-HVDC power synchronous controller for this reason, this controller both can be used for VSC and has been connected with strong AC system and is also applicable to the sight that VSC is connected with weak AC system.Wang Ke, Luo Jian, Yang Shengchun etc. are that the VSC-HVDC powered to passive network starts control research (Proceedings of the CSEE at title, 2011,31st volume, devise the cascade connection type dq decoupling zero pi controller of powering to passive network in document 277-281), the current response rate of this controller is fast and can control AC fault electric current; VSC control system in current Practical Project all adopts cascade connection type dq decoupling zero pi controller structure.
But, above-mentioned research mainly concentrates on VSC-HVDC and is in networking or to the Controller gain variations under the single operational mode of passive island with power, adopts the VSC-HVDC of these control methods stably mutually cannot change between networking operation mode and passive decoupled mode.
Summary of the invention
For the above-mentioned technical problem existing for prior art, the present invention is based on the cascade connection type dq decoupling zero pi controller structure adopted in Practical Project, provide the method for handover control of a kind of VSC-HVDC between networking and decoupled mode, can ensure that VSC-HVDC stably changes between networking operation mode and decoupled mode.
The method for handover control of VSC-HVDC between networking and decoupled mode, comprises the steps:
(1) for the receiving end VSC in VSC-HVDC, detect its control model: if it is in networking control pattern, then perform step (2); If it is in isolated island control model, then perform step (4);
(2) detect receiving end VSC and whether be in decoupled mode: if so, then perform step (3); If not, then the detection that step (1) performs subsequent time is returned;
(3) control model of receiving end VSC is switched to isolated island control model by networking control pattern;
(4) detect receiving end VSC and whether be in networking operation mode: if so, then perform step (5); If not, then the detection that step (1) performs subsequent time is returned;
(5) be networking control pattern by the control model of receiving end VSC by isolated island control mode switch.
The standard detecting receiving end VSC control model in described step (1) is as follows:
The feature being in the receiving end VSC of networking control pattern is: the d axle control ring in receiving end VSC control system adopts and surely exchanges active power is control objectives, q axle control ring adopts and surely exchanges reactive power or determine net top-cross stream voltage effective value is control objectives, and the fixed phase of the transformation matrix of coordinates of abc coordinate system/dq coordinate system and dq coordinate system/abc coordinate system adopts receiving end VSC to net the phase place of side alternating voltage;
The feature being in the receiving end VSC of isolated island control model is: the d axle control ring in receiving end VSC control system adopts and surely nets side alternating voltage d axle component is control objectives, and q axle control ring adopts and surely exchanges reactive power or surely net side alternating voltage q axle component is control objectives.
The standard whether middle receiving end VSC of detection of described step (2) is in decoupled mode is as follows: detect receiving end VSC and whether net the frequency of side alternating voltage higher than upper limiting frequency f maxcontinue T hold1more than second or lower than lower frequency limit f mincontinue T hold2more than second: if so, then judge that receiving end VSC is in decoupled mode; If not, then judge that receiving end VSC is non-and be in decoupled mode; T hold1and T hold2be the default duration.
Switch to the concrete methods of realizing of isolated island control model as follows by networking control pattern the control model of receiving end VSC in described step (3):
A1. changed into determine net side alternating voltage d axle component by surely exchanging active power by the control objectives of the d axle control ring in receiving end VSC control system, the input by control system outer-loop controller changes net side alternating voltage d axle component deviate into by exchanging active power deviate (deviate is that reference value deducts actual measured value);
A2. changed into determine net side alternating voltage q axle component by surely exchanging reactive power or determining net top-cross stream voltage effective value by the control objectives of the q axle control ring in receiving end VSC control system, the input by control system outer-loop controller changes net side alternating voltage q axle component deviate into by the deviate exchanging reactive power deviate or net top-cross stream voltage effective value;
A3. the fixed phase of the transformation matrix of coordinates of abc coordinate system/dq coordinate system and dq coordinate system/abc coordinate system in receiving end VSC control system is set as θ, θ=2 π f 0t+ θ add, f 0for being different from the reference frequency of sending end electrical network rated frequency, θ addfor pattern switching instant receiving end VSC nets the phase place of side alternating voltage, t is the time and timing from pattern switching instant.
Detecting receiving end VSC in described step (4), whether to be in the standard of networking operation mode as follows: detect the difference on the frequency whether overfrequency threshold value f that receiving end VSC nets side alternating current and net side alternating voltage scontinue T hold3more than second: if so, then judge that receiving end VSC is in networking operation mode; If not, then judge that receiving end VSC is non-and be in networking operation mode; T hold3for the duration of presetting.
Be that the concrete methods of realizing of networking control pattern is as follows by the control model of receiving end VSC by isolated island control mode switch in described step (5):
B1. changed into determine interchange active power by surely netting side alternating voltage d axle component by the control objectives of the d axle control ring in receiving end VSC control system, the input by control system outer-loop controller changes into exchange active power deviate by netting side alternating voltage d axle component deviate;
B2. changed into and determine interchange reactive power by surely netting side alternating voltage q axle component or determine net top-cross stream voltage effective value by the control objectives of the q axle control ring in receiving end VSC control system, the input by control system outer-loop controller changes by netting side alternating voltage q axle component deviate the deviate exchanging reactive power deviate or net top-cross stream voltage effective value into;
B3. the fixed phase of the transformation matrix of coordinates of abc coordinate system/dq coordinate system and dq coordinate system/abc coordinate system in receiving end VSC control system is set as that receiving end VSC nets the phase place of side alternating voltage.
The control model of VSC must match with its operational mode.When VSC is in networking operation mode, if VSC still keeps isolated island control model, because the governing system of synchronous generators all in electrical network is for there being poor frequency modulation characteristic, and VSC isolated island control model is constant frequency characteristic, therefore VSC will bear nearly all load active power change, if the meritorious change of network load is more than the meritorious restriction of VSC, VSC will lose steady operation point.Otherwise when VSC is in decoupled mode, if VSC still keeps networking control pattern, the passive island-grid residing for VSC is by frequency of occurrences destabilization problems.Therefore, after the operational mode of VSC changes, its control model need switch as early as possible accordingly.
Whether method of the present invention can the control model of fast detecting VSC mate with operational mode residing for it, and do not mate if find, military order VSC switches to rapidly applicable control model.The method makes VSC precisely can net side active power and reactive power by control VSC when networking operation mode, simultaneously, enable VSC when decoupled mode for passive isolated island provides stable and the voltage waveform of high-quality, therefore, the method for VSC-HVDC conversion mutually between networking operation mode and decoupled mode can ensure that VSC-HVDC stably switches between two kinds of operational modes.
Accompanying drawing explanation
Fig. 1 is the structural representation of VSC and control system thereof.
Fig. 2 is the schematic flow sheet of method for handover control of the present invention.
Fig. 3 is VSC-HVDC and alternating current circuit is the line chart that passive isolated island supplies power with double circuit.
Fig. 4 (a) is the alternating voltage waveform figure of system after the AC12 tripping of alternating current circuit.
Fig. 4 (b) is the frequency oscillogram of system after the AC12 tripping of alternating current circuit.
Fig. 4 (c) is the active power oscillogram of system after the AC12 tripping of alternating current circuit.
Fig. 4 (d) is the reactive power oscillogram of system after the AC12 tripping of alternating current circuit.
Fig. 4 (e) is the bridge arm current oscillogram of VSC2 after the AC12 tripping of alternating current circuit.
Fig. 4 (f) is the parton module capacitance voltage oscillogram of VSC2 after the AC12 tripping of alternating current circuit.
Fig. 5 (a) is the alternating voltage waveform figure of system after the AC12 reclosing of alternating current circuit.
Fig. 5 (b) is the frequency oscillogram of system after the AC12 reclosing of alternating current circuit.
Fig. 5 (c) is the active power oscillogram of system after the AC12 reclosing of alternating current circuit.
Fig. 5 (d) is the reactive power oscillogram of system after the AC12 reclosing of alternating current circuit.
Fig. 5 (e) is the bridge arm current oscillogram of VSC2 after the AC12 reclosing of alternating current circuit.
Fig. 5 (f) is the parton module capacitance voltage oscillogram of VSC2 after the AC12 reclosing of alternating current circuit.
Embodiment
In order to more specifically describe the present invention, below in conjunction with the drawings and the specific embodiments, technical scheme of the present invention is described in detail.
Fig. 1 is VSC and control system basic structure schematic diagram thereof, wherein, and U sfor VSC net side bus alternating voltage effective value, u sjbe respectively VSC net side bus three-phase alternating voltage, subscript j=a, b, c, represent a, b, c three-phase, u respectively sdand u sqbe respectively d axle component and the q axle component of VSC net side bus three-phase alternating voltage, i sjbe respectively VSC net side outlet place three-phase alternating current, i sdand i sqbe respectively d axle component and the q axle component of VSC net side outlet place three-phase alternating current, R and L is respectively VSC AC equivalent resistance and inductance, and V is VSC valve top-cross stream voltage effective value, v jrefbe respectively VSC valve side and export three-phase voltage reference value, v drefand v qrefbe respectively d axle component and q axle component that VSC valve side exports three-phase alternating voltage reference value.I sdref, i sqrefwith for pressing the control signal that the Method and Process shown in Fig. 2 generates, wherein the transformation matrix of coordinates T used by VSC control system abc/dqand T dq/abcfixed phase.
Abc/dq conversion module expression formula is as follows:
T abc / dq = 2 3 · cos θ ^ cos ( θ ^ - 2 π 3 ) cos ( θ ^ + 2 π 3 ) - sin θ ^ - sin ( θ ^ - 2 π 3 ) - sin ( θ ^ + 2 π 3 )
Dq/abc conversion module expression formula is as follows:
T dq / abc = cos θ ^ - sin θ ^ cos ( θ ^ - 2 π 3 ) - sin ( θ ^ - 2 π 3 ) cos ( θ ^ + 2 π 3 ) - sin ( θ ^ + 2 π 3 )
VSC-HVDC as shown in Fig. 1 ~ 2 is at networking operation mode and decoupled mode method for mutually conversing between, and concrete steps are as follows:
(1) detect the control model of receiving end VSC, if receiving end VSC is in networking control pattern, then enter step (2); If receiving end VSC is in isolated island control model, then enter step (4).
VSC control model can be divided into two classes: networking control pattern and isolated island control model.
The receiving end VSC of VSC-HVDC need adopt networking control pattern when being in networking operation mode, VSC networking control pattern is: it is control objectives that VSC net top-cross stream active power is determined in the d axle control ring employing of VSC control system, q axle control ring can adopt to be determined VSC net top-cross stream reactive power or determines VSC net side bus three-phase alternating voltage effective value to be control objectives, controller architecture can adopt prior art, as cascade connection type proportional integral formula dq decoupling zero dual-loop controller.Transformation matrix of coordinates T used by VSC control system abc/dqand T dq/abcfixed phase prior art can be adopted to provide, as PHASE-LOCKED LOOP PLL TECHNIQUE.
The receiving end VSC of VSC-HVDC need adopt isolated island control model when being in decoupled mode, VSC networking control pattern is: it is control objectives that VSC net side bus three-phase alternating voltage d axle component is determined in the d axle control ring employing of VSC control system, q axle control ring can adopt that to determine VSC net side bus three-phase alternating voltage q axle component be control objectives, controller architecture can adopt prior art, as cascade connection type proportional integral formula dq decoupling zero double-closed-loop control device.Transformation matrix of coordinates T used by VSC control system abc/dqand T dq/abcfixed phase by people for presetting, establishing method is as follows:
θ passive=2πf 0t+θ add（1）
In formula 1: θ passivefor artificially given VSC controller fixed phase, f 0for the reference frequency of VSC net side bus three-phase alternating current corrugating, θ addfor the additive phase artificially set.
(2) whether be passive island state, if so, then enter step (3) if detecting receiving end VSC; If not, then step (1) is reentered.
Whether be the determination methods of decoupled mode as follows: whether detect the frequency of receiving end VSC net side bus three-phase alternating voltage higher than upper limiting frequency f if detecting receiving end VSC maxcontinue T hold1more than second or lower than lower frequency limit f mincontinue T hold2more than second: if so, then judge that receiving end VSC is in decoupled mode; If not, then judge that receiving end VSC is non-and be in decoupled mode; T hold1and T hold2for the duration of presetting.
(3) control model is switched to isolated island control model by networking control pattern by receiving end VSC.
Control mode switch is that the method for operation of isolated island control model is as follows by receiving end VSC: changed into determine VSC net side bus three-phase alternating voltage d axle component by determining VSC net top-cross stream active power by the control objectives of VSC control system d axle control ring, the input by outer ring controller changes VSC net side bus three-phase alternating voltage d axle component deviate into by VSC net top-cross stream active power deviate; By the control objectives of VSC control system q axle control ring by determining VSC net top-cross stream reactive power or determine VSC net side bus three-phase alternating voltage effective value to change into and determine VSC and net side three-phase alternating voltage q axle component, changed into the deviate of VSC net side bus three-phase alternating voltage q axle component by the deviate of VSC net top-cross stream reactive power or the deviate of VSC net side bus three-phase alternating voltage effective value by the input of outer ring controller; Transformation matrix T used by VSC control system abc/dqand T dq/abcthe phase place that generated by phase-locked loop of fixed phase change θ into passive.F 0be set to the value different from sending end electrical network rated frequency 50.0Hz (should in 49.5 ~ 50.5 is interval value, as 49.8Hz), the t of formula 1 starts from scratch timing, and θ addequal the phase value of this moment phase-locked loop generation and remain unchanged, the fixed phase can protecting VSC card control mode switch moment transformation matrix of coordinates like this can not be suddenlyd change.
(4) whether be networking operation mode, if so, then enter step (5) if detecting receiving end VSC; If not, then step (1) is reentered.
Whether be the determination methods of networking state as follows: the difference on the frequency whether overfrequency threshold value f detecting receiving end VSC net side outlet place's three-phase alternating current and net side bus three-phase alternating voltage if detecting receiving end VSC scontinue T hold3more than second: if so, then judge that receiving end VSC is in networking operation mode; If not, then judge that receiving end VSC is non-and be in networking operation mode; T hold3for the duration of presetting.
(5) control model is networking control pattern by isolated island control mode switch by receiving end VSC.
Control mode switch is that the method for operation of isolated island control model is as follows by receiving end VSC: the control objectives of VSC control system d axle control ring is netted side three-phase alternating voltage d axle component and changed into by determining VSC and determine VSC net top-cross stream active power, and the input by outer ring controller is netted side three-phase alternating voltage d axle component deviate by VSC and changed VSC net top-cross stream active power deviate into; The control objectives of VSC control system q axle control ring is netted side three-phase alternating voltage q axle component and changed into by determining VSC and determine VSC net top-cross stream reactive power or determine VSC to net side three-phase alternating voltage effective value, and the deviate that the input by outer ring controller nets side three-phase alternating voltage q axle component by VSC changes the deviate of VSC net top-cross stream reactive power or the deviate of VSC net side three-phase alternating voltage effective value into; Transformation matrix T used by VSC control system abc/dqand T dq/abcfixed phase by θ passivechange the phase place that phase-locked loop generates into.
Fig. 3 is VSC-HVDC and alternating current circuit is the line chart that passive isolated island supplies power with double circuit, sending end VSC1 and receiving end VSC2 is modularization multi-level converter, submodule quantity is 160, rated direct voltage is ± 200kV, two ends converter adopts the electric voltage equalization strategy based on submodule capacitor voltage sequence, modulation strategy is nearest level approach method, all adopts loop current suppression strategy.Sending end VSC1 adopts and determines direct voltage and determine Reactive Power Control, and receiving end VSC2 adopts networking operation mode and the decoupled mode method for mutually conversing between of present embodiment, VSC2 networking control mode parameter: P sref=200MW, Q sref=50Mvar.VSC2 isolated island control model parameter: f 0=49.8Hz, u sdref=1.00pu.Islanding detect criterion: f max=50.5Hz, f min=49.5Hz, T hold1=0.2s, T hold2=0.2s.Networking detection criteria: f s=0.2Hz, T hold3=0.2s.In Fig. 1, AC system AC0 and AC1 all represents by impedance after-potential, and both are 112kV by line voltage effective value, and reference frequency is 50.0Hz, and impedance is 0.2+j1.0 Ω.The impedance of alternating current circuit AC12 is 2.0+j6.0 Ω.The resistance of DC line DC12 is 5 Ω.Receiving end island-grid load represents, active power and the reactive power of load are respectively 300MW and 120Mvar, and load is constant-impedance characteristic.B2 is VSC net side bus.
Fig. 4 is after adopting present embodiment conversion method, the system transient modelling process after the AC12 tripping of alternating current circuit.During electric power system initial condition shown in Fig. 3, alternating current circuit AC12 is in connection status, and system stable operation is to 1.0s, and alternating current circuit AC12 tripping, ac bus B2 three-phase metallic earthing during 2.0s, fault is removed after continuing 0.2s.During receiving end VSC2 networking steady operation, bus B2 line voltage effective value is 106kV, and receiving end mains frequency is that 50.0Hz, VSC2 net side active power and reactive power is respectively 200MW and 50Mvar.During 1.0s after AC12 tripping, about during 1.205s, VSC2 net side bus B2 three-phase alternating voltage frequency continues 0.2s more than 50.5Hz, VSC2 proceeds to isolated island control model at once, after this three-phase alternating voltage effective value of ac bus B2 returns to 110kV very soon, receiving end mains frequency is stabilized in 49.8Hz, and receiving end electrical network reaches stable state very soon; When system cloud gray model is to 2.0s, there is three-phase metallic earthing fault in bus B2, after 2.2s fault clearance, system can be recovered smoothly.The AC12 tripping of above-mentioned alternating current circuit, VSC2 switch in three processes of isolated island control model and AC fault, and bridge arm current and the submodule capacitor voltage of VSC2 all remain on zone of reasonableness.
Fig. 5 is after adopting present embodiment conversion method, the system transient modelling process after the AC12 reclosing of alternating current circuit.During electric power system initial condition shown in Fig. 4, alternating current circuit AC12 is in off-state, and when system stable operation is to 1.0s, the success of alternating current circuit AC12 synchronous recloser, during combined floodgate, circuit breaker BRK2 both sides line voltage distribution phase difference is 5 °.After the AC12 reclosing of 1.0s alternating current circuit, VSC2 net side bus B2 alternating current voltage frequency remains on 49.8Hz substantially, sending end AC system AC1 frequency is 50.0Hz, because both frequencies are asynchronous, VSC2 net side outlet place AC current frequency will depart from VSC2 net side bus B2 alternating current voltage frequency, VSC2 nets side active power and constantly reduces and net side reactive power constantly to increase, about during 1.205s, the difference of VSC2 net side AC current frequency and VSC2 net side alternating current voltage frequency continues 0.2s more than 0.2Hz, VSC2 proceeds to networking control pattern at once, after this VSC2 nets side active power and is adjusted to 200MW very soon, net side reactive power is adjusted to 50Mvar, receiving end mains frequency returns to 50.0Hz, system is adjusted to stable networking state very soon.Above-mentioned alternating current circuit reclosing and VSC2 switch in two processes of networking control pattern, and bridge arm current and the submodule capacitor voltage of VSC2 all remain on zone of reasonableness.
Therefore in networking operation mode and decoupled mode method for mutually conversing between, VSC-HVDC of the present invention can ensure that VSC-HVDC stably switches between networking and isolated island two kinds of operational modes.

Claims (3)

1. the method for handover control of VSC-HVDC between networking and decoupled mode, comprises the steps:
(1) for the receiving end VSC in VSC-HVDC, detect its control model: if it is in networking control pattern, then perform step (2); If it is in isolated island control model, then perform step (4);
Concrete examination criteria is as follows:
The feature being in the receiving end VSC of networking control pattern is: the d axle control ring in receiving end VSC control system adopts and surely exchanges active power is control objectives, q axle control ring adopts and surely exchanges reactive power or determine net top-cross stream voltage effective value is control objectives, and the fixed phase of the transformation matrix of coordinates of abc coordinate system/dq coordinate system and dq coordinate system/abc coordinate system adopts receiving end VSC to net the phase place of side alternating voltage;
The feature being in the receiving end VSC of isolated island control model is: the d axle control ring in receiving end VSC control system adopts and surely nets side alternating voltage d axle component is control objectives, and q axle control ring adopts and surely exchanges reactive power or surely net side alternating voltage q axle component is control objectives;
(2) detect receiving end VSC and whether be in decoupled mode: if so, then perform step (3); If not, then the detection that step (1) performs subsequent time is returned;
(3) control model of receiving end VSC is switched to isolated island control model by networking control pattern, concrete methods of realizing is as follows:
A1. changed into determine net side alternating voltage d axle component by surely exchanging active power by the control objectives of the d axle control ring in receiving end VSC control system, the input by control system outer-loop controller changes net side alternating voltage d axle component deviate into by exchanging active power deviate;
A2. changed into determine net side alternating voltage q axle component by surely exchanging reactive power or determining net top-cross stream voltage effective value by the control objectives of the q axle control ring in receiving end VSC control system, the input by control system outer-loop controller changes net side alternating voltage q axle component deviate into by the deviate exchanging reactive power deviate or net top-cross stream voltage effective value;
A3. the fixed phase of the transformation matrix of coordinates of abc coordinate system/dq coordinate system and dq coordinate system/abc coordinate system in receiving end VSC control system is set as θ, θ=2 π f 0t+ θ add, f 0for being different from the reference frequency of sending end electrical network rated frequency, θ addfor pattern switching instant receiving end VSC nets the phase place of side alternating voltage, t is the time and timing from pattern switching instant;
(4) detect receiving end VSC and whether be in networking operation mode: if so, then perform step (5); If not, then the detection that step (1) performs subsequent time is returned;
(5) be networking control pattern by the control model of receiving end VSC by isolated island control mode switch, concrete methods of realizing is as follows:
B1. changed into determine interchange active power by surely netting side alternating voltage d axle component by the control objectives of the d axle control ring in receiving end VSC control system, the input by control system outer-loop controller changes into exchange active power deviate by netting side alternating voltage d axle component deviate;
B2. changed into and determine interchange reactive power by surely netting side alternating voltage q axle component or determine net top-cross stream voltage effective value by the control objectives of the q axle control ring in receiving end VSC control system, the input by control system outer-loop controller changes by netting side alternating voltage q axle component deviate the deviate exchanging reactive power deviate or net top-cross stream voltage effective value into;
B3. the fixed phase of the transformation matrix of coordinates of abc coordinate system/dq coordinate system and dq coordinate system/abc coordinate system in receiving end VSC control system is set as that receiving end VSC nets the phase place of side alternating voltage.
2. method for handover control according to claim 1, is characterized in that: the standard whether middle receiving end VSC of detection of described step (2) is in decoupled mode is as follows: detect receiving end VSC and whether net the frequency of side alternating voltage higher than upper limiting frequency f maxcontinue T hold1more than second or lower than lower frequency limit f mincontinue T hold2more than second: if so, then judge that receiving end VSC is in decoupled mode; If not, then judge that receiving end VSC is non-and be in decoupled mode; T hold1and T hold2be the default duration.
3. method for handover control according to claim 1, is characterized in that: detecting receiving end VSC in described step (4), whether to be in the standard of networking operation mode as follows: detect the difference on the frequency whether overfrequency threshold value f that receiving end VSC nets side alternating current and net side alternating voltage scontinue T hold3more than second: if so, then judge that receiving end VSC is in networking operation mode; If not, then judge that receiving end VSC is non-and be in networking operation mode; T hold3for the duration of presetting.
CN201410120088.0A 2014-03-27 2014-03-27 The method for handover control of a kind of VSC-HVDC between networking and decoupled mode Expired - Fee Related CN103904677B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201410120088.0A CN103904677B (en) 2014-03-27 2014-03-27 The method for handover control of a kind of VSC-HVDC between networking and decoupled mode

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201410120088.0A CN103904677B (en) 2014-03-27 2014-03-27 The method for handover control of a kind of VSC-HVDC between networking and decoupled mode

Publications (2)

Publication Number Publication Date
CN103904677A CN103904677A (en) 2014-07-02
CN103904677B true CN103904677B (en) 2015-09-23

Family

ID=50995878

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201410120088.0A Expired - Fee Related CN103904677B (en) 2014-03-27 2014-03-27 The method for handover control of a kind of VSC-HVDC between networking and decoupled mode

Country Status (1)

Country Link
CN (1) CN103904677B (en)

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105743136B (en) * 2014-12-11 2017-12-22 南京南瑞继保电气有限公司 Suppress the method that multiple current conversion stations enter Passive Shape Control pattern under a kind of island state
CN104485683B (en) * 2014-12-23 2018-07-06 南京南瑞继保电气有限公司 A kind of isolated island turns networking method
CN104682751B (en) * 2015-03-02 2017-07-25 上海交通大学 Modularization based on PAM and PWM hybrid modulations cascades multilevel converter
CN105576688B (en) * 2015-12-28 2020-07-07 国网辽宁省电力有限公司电力科学研究院 Control protection method of flexible direct current transmission system
CN106451458A (en) * 2016-09-18 2017-02-22 许继集团有限公司 Reactive control method and reactive controller for flexible direct current power transmission network
CN108023337B (en) 2016-10-31 2019-07-23 南京南瑞继保电气有限公司 A kind of flexible HVDC transmission system inverter operates in failure current limit control and protection fitting method under island state
CN107039992B (en) * 2017-03-23 2020-02-21 许继电气股份有限公司 Starting control method and system of MMC (modular multilevel converter) converter based on droop control
CN107623333B (en) * 2017-09-05 2020-09-29 华北电力大学 Distributed photovoltaic output current analysis method for dynamic reclosing process of phase-locked loop
CN108344902B (en) * 2017-10-24 2021-06-29 广东电网有限责任公司汕头供电局 Power loss judgment method and device for flexible direct current power transmission device facing inspection personnel
CN109659950B (en) * 2018-12-29 2022-03-04 国家电网有限公司 Reactive power control system and method of voltage source converter with variable lower limit voltage
CN110231545B (en) * 2019-07-08 2021-06-29 四川大学 Island detection method and reference current extreme value calculation method for alternating current-direct current series-parallel power grid
CN110797901B (en) * 2019-11-19 2023-05-05 许继电气股份有限公司 Extra-high voltage hybrid direct-current transmission VSC alternating-current section power loss identification method and device
CN111130141B (en) * 2020-01-17 2022-10-04 中国电力科学研究院有限公司 Switching controller for networking and isolated island operation of flexible direct current converter station
CN112564176B (en) * 2020-11-25 2024-06-04 漳州科华技术有限责任公司 Micro-network presynchronization method and system based on temporary master-slave switching

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103346582A (en) * 2013-06-21 2013-10-09 南方电网科学研究院有限责任公司 Seamless switching method for station-level control mode of flexible direct-current transmission system
CN103647286A (en) * 2013-11-15 2014-03-19 许继集团有限公司 Modularization multi-level converter island switching control method

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3164701B2 (en) * 1993-07-23 2001-05-08 東京電力株式会社 Inverter control device for grid interconnection

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103346582A (en) * 2013-06-21 2013-10-09 南方电网科学研究院有限责任公司 Seamless switching method for station-level control mode of flexible direct-current transmission system
CN103647286A (en) * 2013-11-15 2014-03-19 许继集团有限公司 Modularization multi-level converter island switching control method

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
向无源网络供电的VSC-HVDC系统的控制器设计;陈海荣;《中国电机工程学报》;20061231;第26卷(第23期);第42-48页 *
韦廷真.提高VSC-HVDC系统向无源网络供电可靠性的方法探究.《中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑(月刊)》.2013,(第10期), *

Also Published As

Publication number Publication date
CN103904677A (en) 2014-07-02

Similar Documents

Publication Publication Date Title
CN103904677B (en) The method for handover control of a kind of VSC-HVDC between networking and decoupled mode
CN103904676B (en) The droop control method of a kind of VSC-HVDC
Mahela et al. Power quality improvement in distribution network using DSTATCOM with battery energy storage system
CN107591839B (en) Excitation state analysis-based virtual synchronous generator low voltage ride through control method
Tummuru et al. Control strategy for AC-DC microgrid with hybrid energy storage under different operating modes
CN104319757B (en) The arc suppression coil device and method of active component in compensation single-phase earth fault current
CN102545260B (en) Method for controlling automatic seamless switching between grid-connected mode and grid-isolated mode of microgrid
CN104184151B (en) A kind of dynamic electric voltage recovery device realizing the different operational mode of microgrid and take over seamlessly
CN101728858B (en) Uninterruptible power supply and method for tripping thereof
CN104135009B (en) A kind of parallel connection type Unified Power Quality Controller and progress control method thereof
CN103414204B (en) Adopt the control method of dynamic voltage compensation wind generator system output reactive power
CN1937349A (en) Comprehensive dynamic compensating device for distribution network
CN107046377B (en) A kind of two-way alternating current-direct current energy storage converter failure tolerant pressure equalizing control method
CN103219722A (en) Method for improving failure recovery characteristics of large-scale wind electricity through direct current outgoing system
CN104578736A (en) Control method for converter current-limiting protection based on dynamic vector amplitude limit and converter
Yu et al. Indirect current control algorithm for utility interactive inverters for seamless transfer
CN104393591A (en) Power supply system
CN108879789A (en) Bidirectional energy-storage Variable flow control device and method
CN110376472B (en) Photovoltaic grid-connected inverter island detection method based on double-loop current negative feedback control
CN108777487B (en) Circuit link between alternating current-direct current hybrid micro-grid and power distribution network and control method
CN207166122U (en) The protection device and micro-capacitance sensor of a kind of grounding transformer
CN110247433B (en) Photovoltaic grid-connected island detection method based on improved sliding mode frequency shift method
Zheng et al. Technology and engineering application of cross area HVDC interconnection system high-precision simulation modeling based on ADPSS
Rizo et al. Universal wind turbine working in grid-connected and island operating modes
CN209462035U (en) Bidirectional energy-storage Variable flow control device

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20150923

Termination date: 20180327

CF01 Termination of patent right due to non-payment of annual fee