CN110071518A - A kind of combined type direct-current unloading circuit based on arrester - Google Patents

A kind of combined type direct-current unloading circuit based on arrester Download PDF

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Publication number
CN110071518A
CN110071518A CN201910251977.3A CN201910251977A CN110071518A CN 110071518 A CN110071518 A CN 110071518A CN 201910251977 A CN201910251977 A CN 201910251977A CN 110071518 A CN110071518 A CN 110071518A
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CN
China
Prior art keywords
arrester
circuit
combined type
load
current
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Pending
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CN201910251977.3A
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Chinese (zh)
Inventor
许超群
曾嵘
余占清
赵彪
张翔宇
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Tsinghua University
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Tsinghua University
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Priority to CN201910251977.3A priority Critical patent/CN110071518A/en
Publication of CN110071518A publication Critical patent/CN110071518A/en
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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02JCIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00Circuit arrangements for ac mains or ac distribution networks
    • H02J3/12Circuit arrangements for ac mains or ac distribution networks for adjusting voltage in ac networks by changing a characteristic of the network load
    • H02J3/14Circuit arrangements for ac mains or ac distribution networks for adjusting voltage in ac networks by changing a characteristic of the network load by switching loads on to, or off from, network, e.g. progressively balanced loading
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02JCIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00Circuit arrangements for ac mains or ac distribution networks
    • H02J3/36Arrangements for transfer of electric power between ac networks via a high-tension dc link
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02BCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/30Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
    • Y02B70/3225Demand response systems, e.g. load shedding, peak shaving
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/60Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]
    • YGENERAL 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
    • Y04INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
    • Y04SSYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
    • Y04S20/00Management or operation of end-user stationary applications or the last stages of power distribution; Controlling, monitoring or operating thereof
    • Y04S20/20End-user application control systems
    • Y04S20/222Demand response systems, e.g. load shedding, peak shaving

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Emergency Protection Circuit Devices (AREA)

Abstract

The invention discloses a kind of combined type direct-current unloading circuit based on arrester, including the off-load branch at least all the way being connected between the positive route of DC power transmission line and anode circuit;The off-load branch includes one or more direct current off-load submodule;The multiple direct current off-load submodule is connected between the positive route of DC power transmission line and anode circuit;The direct current off-load submodule includes electrode input end and cathode output end, and chopper circuit and arrester are connected between electrode input end and negative input.The present invention reduces the dv/dt and di/dt of circuit by modular design.By eliminating bulky off-load capacitor, single off-load submodule volume reduces 30% or more.And cost is considerably reduced, a reverse blocking diode and off-load capacitor is omitted, reduces the capacity of electric power generation unloading resistance and switching device.The series connection of multiple groups module can share the voltage of DC power transmission line, and switching device is avoided to bear too high voltages and damage.

Description

A kind of combined type direct-current unloading circuit based on arrester
Technical field
The invention belongs to technical field of direct current power transmission, in particular to a kind of combined type direct current based on arrester unloads charged Road.
Background technique
In recent years, high voltage dc transmission technology obtains high speed development, offshore grid-connected wind farm flexible HVDC transmission system (VSC-HVDC) using more and more extensive.VSC-HVDC operate normally when, what Wind turbines isolated island mode issued when accessing Energy and the energy of receiving end AC network consumption keep balancing.And when receiving end AC network breaks down, consumable energy Amount reduces, and receives the ability of power limited.And frequency and voltage letter of the sending end wind power plant since AC network can not be directly obtained Breath, voltage and frequency will not change in the short time, and energy is caused to accumulate on DC line, and it is how electric that surplus power flows into modularization Flat inverter, power distribution schematic diagram when marine wind electric field isolated island mode as shown in Figure 1 accesses, the modular multilevel change of current The capacitor of device (MMC) is electrically charged, and voltage rises, and causes AC line voltage to rise indirectly.If receiving end converter station is to DC line Control failure, will lead to route tripping when serious.
To avoid failure, need to consume surplus power using the mode of energy consumption using direct-current unloading circuit, such as Fig. 2 institute Show using direct-current unloading circuit when power distribution schematic diagram it is flat to be reached by the power of chopper circuit control consumption for power Weighing apparatus.Due to using switch series connection interconnection technique, the dynamic static state voltage equipoise of switching device is difficult to realize lumped resistance copped wave discharging circuit, Dv/dt is very big with di/dt, such as patent publication No. CN101136582B, discloses a kind of full power convertor DC side-discharging The control method of circuit, discharging circuit therein are made of power device and electric power generation unloading resistance.
More level discharging circuits can also effectively reduce current fluctuation using modularized design, preferably realize sound State is pressed, but uses the semiconductor devices of many large capacities, and circuit cost is high, bulky, such as patent No. bulletin Number CN102856909B, the modular multilevel wind electric converter of a kind of disclosed Load Relief System and the application Load Relief System, needle The characteristics of multiple cascade of power units are used to modular multilevel wind electric converter topological structure, in each cascaseded power cell Individual discharging circuit is respectively set.
It can be seen that one kind is needed to effectively reduce current fluctuation, the direct-current unloading circuit of dynamic static state voltage equipoise is realized.
Summary of the invention
In view of the above-mentioned problems, the present invention provides a kind of combined type direct-current unloading circuit based on arrester, including it is connected to Off-load branch at least all the way between the positive route and anode circuit of DC power transmission line;
The off-load branch includes one or more direct current off-load submodule;
The multiple direct current off-load submodule is connected between the positive route of DC power transmission line and anode circuit;
The direct current off-load submodule includes electrode input end and cathode output end, electrode input end and negative input it Between connect chopper circuit and arrester.
Preferably, the chopper circuit parallel connection buffer circuit carries out buffer protection to chopper circuit.
Preferably, the buffer circuit include buffering resistance-capacitance circuit, the buffering resistance-capacitance circuit includes resistance, and with electricity Concatenated capacitor is hindered, the resistance connects electrode input end, and the capacitor is connect with cathode output end.
Preferably, by-pass switch is connected between the electrode input end and cathode output end.
Preferably, diode is connected between the electrode input end and cathode output end, the positive electrode and negative electrode of diode are defeated Outlet connection, the cathode of diode are connect with electrode input end.
Preferably, the chopper circuit includes the energy dissipation device of at least one set of switching device and at least one set, switch Device and energy dissipation device are connected between electrode input end and cathode output end.
Preferably, the energy dissipation device includes electric power generation unloading resistance.
Preferably, the switching device uses full-controlled switch pipe.
Preferably, the switching device reverse parallel connection freewheeling diode.
Preferably, the arrester includes metal oxide arrester.
The beneficial effects of the present invention are:
The sound state that the combined type direct-current unloading circuit based on arrester of the technical program can be realized switching device is equal Pressure, it is modular to design the dv/dt and di/dt for reducing circuit.By eliminating bulky off-load capacitor, single off-load Submodule volume reduces 30% or more.And cost is considerably reduced, a reverse blocking diode and off-load capacitor is omitted, subtracts The small capacity of electric power generation unloading resistance and switching device.The series connection of multiple groups module can share the voltage of DC power transmission line, avoid out Device is closed to bear too high voltages and damage.
Other features and advantages of the present invention will be illustrated in the following description, also, partly becomes from specification It obtains it is clear that understand through the implementation of the invention.The objectives and other advantages of the invention can be by specification, right Pointed structure is achieved and obtained in claim and attached drawing.
Detailed description of the invention
In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below There is attached drawing needed in technical description to be briefly described, it should be apparent that, the accompanying drawings in the following description is this hair Bright some embodiments for those of ordinary skill in the art without creative efforts, can be with root Other attached drawings are obtained according to these attached drawings.
Power distribution schematic diagram when the marine wind electric field isolated island mode that Fig. 1 shows the prior art accesses;
Power distribution schematic diagram when Fig. 2 shows the prior arts using direct-current unloading circuit;
Fig. 3 shows the usage state diagram of direct current off-load submodule of the invention;
Fig. 4 shows the topological structure schematic diagram of the direct current off-load submodule SM of the first embodiment of the invention;
Fig. 5 shows the topological structure schematic diagram of the direct current off-load submodule SM of second of embodiment of the invention;
Fig. 6 shows the topological structure schematic diagram of the direct current off-load submodule SM of the third embodiment of the invention;
Fig. 7 shows the topological structure schematic diagram of the direct current off-load submodule SM of the 4th kind of embodiment of the invention;
Fig. 8 shows the control method block diagram of the combined type direct-current unloading circuit of the invention based on arrester;
Fig. 9 show the combined type direct-current unloading circuit of the invention based on arrester submodule pulse signal control and Voltage measurement schematic diagram;
Figure 10 shows the submodule pulse Collaborative Control of the combined type direct-current unloading circuit of the invention based on arrester Method figure.
Specific embodiment
In order to make the object, technical scheme and advantages of the embodiment of the invention clearer, below in conjunction with the embodiment of the present invention In attached drawing, technical solution in the embodiment of the present invention clearly and completely illustrated, it is clear that described embodiment is A part of the embodiment of the present invention, instead of all the embodiments.Based on the embodiments of the present invention, those of ordinary skill in the art Every other embodiment obtained without making creative work, shall fall within the protection scope of the present invention.
The present invention provides the combined type direct-current unloading circuit based on arrester for being applied to direct current transportation, in DC transmission line Off-load branch at least all the way is set between the positive route and anode circuit on road, and off-load branch includes one or more direct current Off-load submodule, multiple direct current off-load submodules are connected between the positive route of DC power transmission line and anode circuit.Pass through The lightning arrester connected in parallel in Traditional DC discharging circuit forms combined type direct-current unloading circuit, and by combined type direct-current unloading circuit Modularized processing is carried out with arrester and forms direct current off-load submodule, and the direct current off-load submodule of several groups is connected, passed through The concatenated quantity of direct current off-load submodule is improved, the dv/dt (voltage increase rate) and di/dt (electric current liter of entire circuit are reduced Upper rate), keep power regulation characteristic more smooth.A kind of combined type direct-current unloading circuit based on arrester, including n direct current Off-load submodule SM: direct current off-load submodule SM1, direct current off-load submodule SMi, direct current off-load submodule SMn, n is any positive integer, and i is any positive integer more than or equal to 1 and less than or equal to n, and direct current off-load submodule SM includes just Pole input terminal and cathode output end, the positive and negative anodes of n direct current off-load submodule SM are connected on the positive route of DC line and bear Among polar curve road.By flexibly using the number of direct current off-load submodule SM, the pressure-resistant and through-flow of turn-off device is reasonably selected Ability can be designed the combined type direct-current unloading circuit for different occasions, and direct current off-load submodule SM cascade quantity is more, directly The dv/dt and di/dt of current circuit are smaller, and power regulation characteristic is more smooth.
Direct current off-load submodule includes electrode input end and cathode output end, is connected between electrode input end and negative input Connect chopper circuit and arrester, it is more that the arrester can be used type, including metal oxide arrester, line type metal Oxide Arrester, gapless Line type's MOA, all insulation polymeric metal oxide surge arrester and Detachable lightning arrester etc..The chopper circuit parallel connection buffer circuit carries out buffer protection to chopper circuit.The buffer circuit packet Buffering resistance-capacitance circuit is included, the buffering resistance-capacitance circuit includes resistance and capacitor in series with a resistor, the resistance connection anode Input terminal, the capacitor are connect with cathode output end.By-pass switch is connected between the electrode input end and cathode output end.Institute It states and connects diode between electrode input end and cathode output end, the positive electrode and negative electrode output end connection of diode, diode Cathode is connect with electrode input end.The chopper circuit includes the energy consumer of at least one set of switching device and at least one set Part, switching device and energy dissipation device are connected between electrode input end and cathode output end.The energy dissipation device is charged including unloading Resistance, the switching device reverse parallel connection freewheeling diode.
For ease of description, it is only illustrated by taking the applicable cases of direct current off-load submodule SM in marine wind electric field as an example, And an off-load branch is at sea used only in the DC power transmission line of wind power plant.It should be noted that direct current of the invention Off-load submodule SM is applicable not only to the application of marine wind electric field, applies also for other DC power transmission lines, and off-load branch Quantity may be multiple groups, quantity can according to need carry out installation settings.
Illustratively, Fig. 3 shows the usage state diagram of direct current off-load submodule SM, more direct current off-load submodule SM strings It is associated between the positive route of marine wind electric field DC power transmission line and anode circuit.Wherein, First direct current off-load submodule SM1Electrode input end connection marine wind electric field DC power transmission line positive route;(i-1)-th direct current off-load submodule SMi-1 Cathode output end be connected to i-th direct current off-load submodule SMiCathode output end;N-th direct current off-load submodule SMn's Cathode output end is connected to the anode circuit of marine wind electric field DC power transmission line.
As the first embodiment of the invention, the topological structure schematic diagram of direct current off-load submodule SM shown in Fig. 4, Direct current off-load submodule SM includes concatenated switch transistor T and electric power generation unloading resistance Ri, pass through electric power generation unloading resistance RiConsume surplus power, switch For pipe T as switching device, the all-controlling power electronics devices such as IGBT, IGCT are can be used in switch transistor T.The collector of switch transistor T connects It is connected to electrode input end, the emitter of switch transistor T is connected to electric power generation unloading resistance Ri, electric power generation unloading resistance RiIt is connected to negative input, anode Arrester MOV (metal oxide arrester) is connected between input terminal and cathode output end, was strictly limited using arrester MOV Voltage guarantees equalizing effect;Dynamic static state voltage equipoise and transient condition lower switch pipe are realized by arrester MOV and buffering resistance-capacitance circuit The over-voltage and overcurrent protection of T, improves the reliability of switch transistor T.
As second of embodiment of the invention, the topological structure schematic diagram of direct current off-load submodule SM shown in fig. 5, Direct current off-load submodule SM includes concatenated switch transistor T and electric power generation unloading resistance Ri, pass through electric power generation unloading resistance RiConsume surplus power, switch For pipe T as switching device, the all-controlling power electronics devices such as IGBT, IGCT are can be used in switch transistor T.The collector of switch transistor T connects It is connected to electrode input end, the emitter of switch transistor T is connected to electric power generation unloading resistance Ri, electric power generation unloading resistance RiIt is connected to negative input, is switched Pipe T and electric power generation unloading resistance RiParallel connection buffer resistance-capacitance circuit after series connection, buffering resistance-capacitance circuit includes resistance RSWith capacitor CS, resistance RSEven It is connected to electrode input end, capacitor CSIt is connected to cathode output end, when can slow down switch transistor T shutdown by buffering resistance-capacitance circuit, is opened The rate of voltage rise of pipe T is closed, dynamic differential pressure is reduced.It buffers resistance-capacitance circuit lightning arrester connected in parallel MOV (metal oxide arrester), Using the stringent over-voltage of arrester MOV, guarantee equalizing effect;Sound is realized by arrester MOV and buffering resistance-capacitance circuit State is pressed and the over-voltage and overcurrent protection of transient condition lower switch pipe T, improves the reliability of switch transistor T.
As the third embodiment of the invention, the topological structure schematic diagram of direct current off-load submodule SM shown in fig. 6, Direct current off-load submodule SM includes concatenated switch transistor T and electric power generation unloading resistance Ri, pass through electric power generation unloading resistance RiConsume surplus power, switch For pipe T as switching device, the all-controlling power electronics devices such as IGBT, IGCT are can be used in switch transistor T.The collector of switch transistor T connects It is connected to electrode input end, the emitter of switch transistor T is connected to electric power generation unloading resistance Ri, electric power generation unloading resistance RiIt is connected to negative input, is switched Pipe T and electric power generation unloading resistance RiParallel connection buffer resistance-capacitance circuit after series connection, buffering resistance-capacitance circuit includes resistance RSWith capacitor CS, resistance RSEven It is connected to electrode input end, capacitor CSIt is connected to cathode output end, when can slow down switch transistor T shutdown by buffering resistance-capacitance circuit, is opened The rate of voltage rise of pipe T is closed, dynamic differential pressure is reduced.It buffers resistance-capacitance circuit lightning arrester connected in parallel MOV (metal oxide arrester), Using the stringent over-voltage of arrester MOV, guarantee equalizing effect;Sound is realized by arrester MOV and buffering resistance-capacitance circuit State is pressed and the over-voltage and overcurrent protection of transient condition lower switch pipe T, improves the reliability of switch transistor T.The resistance-capacitance circuit is also Paralleling switch S, by-pass switch S play bypass functionality, resistance-capacitance circuit by-pass switch S also in parallel when being off-load sub-module fault It is diode with diode D, D, bears counter voltage damage to prevent off-load submodule to be reversely connected, the cathode and anode of diode D The cathode of input terminal connection, diode D connects cathode output end.
As the 4th kind of embodiment of the invention, the topological structure schematic diagram of direct current off-load submodule SM shown in Fig. 7, Direct current off-load submodule SM includes concatenated switch transistor T and electric power generation unloading resistance Ri, pass through electric power generation unloading resistance RiConsume surplus power, switch For pipe T as switching device, the all-controlling power electronics devices such as IGBT, IGCT are can be used in switch transistor T.The collector of switch transistor T connects It is connected to electrode input end, the emitter of switch transistor T is connected to electric power generation unloading resistance Ri, electric power generation unloading resistance RiIt is connected to negative input, is switched Pipe T and electric power generation unloading resistance RiParallel connection buffer resistance-capacitance circuit after series connection, buffering resistance-capacitance circuit includes resistance RSWith capacitor CS, resistance RSEven It is connected to electrode input end, capacitor CSIt is connected to cathode output end, when can slow down switch transistor T shutdown by buffering resistance-capacitance circuit, is opened The rate of voltage rise of pipe T is closed, dynamic differential pressure is reduced.It buffers resistance-capacitance circuit lightning arrester connected in parallel MOV (metal oxide arrester), Using the stringent over-voltage of arrester MOV, guarantee equalizing effect;Sound is realized by arrester MOV and buffering resistance-capacitance circuit State is pressed and the over-voltage and overcurrent protection of transient condition lower switch pipe T, improves the reliability of switch transistor T.The resistance-capacitance circuit is also Paralleling switch S, by-pass switch S play bypass functionality, resistance-capacitance circuit by-pass switch S also in parallel when being off-load sub-module fault It is diode with diode D, D, bears counter voltage damage to prevent off-load submodule to be reversely connected, the cathode and anode of diode D Input terminal connection, the cathode of diode D connect cathode output end, and D is used as diode, prevent direct current off-load submodule SM reversal connection and Bear counter voltage damage.Switching tube reverse parallel connection freewheeling diode, is protected by freewheeling diode switch tube.
The sound state that the combined type direct-current unloading circuit based on arrester of the technical program can be realized switching device is equal Pressure, it is modular to design the dv/dt and di/dt for reducing circuit.By eliminating bulky off-load capacitor, single off-load Submodule volume reduces 30% or more.And cost is considerably reduced, a reverse blocking diode and off-load capacitor is omitted, subtracts The small capacity of electric power generation unloading resistance and switching device.
The technical program additionally provides a kind of control method of combined type direct-current unloading circuit based on arrester, based on keeping away The combined type direct-current unloading circuit of thunder device at runtime, monitors the positive route of DC power transmission line voltage in real time, when More than after given threshold, combined type direct current off-load module is triggered the voltage of positive route.
The control method block diagram of combined type direct-current unloading circuit based on arrester as shown in Figure 8, control method include, Detect net side converter station DC input power (Pin_G) with exchange side output power (Pout_G), calculate (Pout_G-Pin_G) net side changes Stream station DC input power (Pin_G) with exchange side output power (Pout_G) power difference, obtain the combined type based on arrester The power difference (△ P) that direct-current unloading circuit should consume.
The signal of power difference is handled by proportional component and division link, obtains the control letter of discharging circuit Number, proportional component and division link are determined by the per unit value and off-load submodule design value of power difference.
Measure DC power transmission line voltage measuring value Edc, and with DC power transmission line voltage reference value Edc_refIt is compared, Obtain discharging circuit trigger signal.Specifically, by DC power transmission line voltage measuring value EdcWith DC power transmission line Voltage Reference Value Edc_refIt is compared by comparator, as DC power transmission line voltage measuring value EdcHigher than DC power transmission line Voltage Reference Value Edc_refWhen, high level signal is exported by comparator;By DC power transmission line voltage measuring value EdcWith DC power transmission line electricity Press reference value Edc_refIt is compared by comparator, as DC power transmission line voltage measuring value EdcNot higher than DC power transmission line Voltage reference value Edc_refWhen, low level signal is exported by comparator.
Discharging circuit controls signal and discharging circuit trigger signal and carries out multiplication process by multiplication link, and passes through clipping Link carries out amplitude limiting processing to the control signal Jing Guo multiplication process, obtains the duty ratio of control switch device, passes through clipping ring Save duty ratio of the generation value between 0-1.
The adjustable triangular carrier signal of frequency is obtained from signal generator or other signal generation apparatus, and according to duty Than the pulse signal of corresponding frequencies and duty ratio, the copped wave of control switch device can be obtained by comparator.
Illustratively, when at sea the net side converter station of wind power plant fails to the control of DC line, the net side change of current is detected DC input power of standing is Pin_GWith exchange side output power Pout_G, calculate net side converter station DC input power Pin_GWith exchange Side output power Pout_GPower difference be Pout_G-Pin_G=△ P obtains the combined type direct-current unloading circuit based on arrester and answers The power difference of the consumption.The signal of power difference is handled by proportional component and division link, obtains discharging circuit Control signal, proportional component and division link are determined by the per unit value and off-load submodule design value of power difference.
Also, the DC power transmission line voltage measuring value that measurement obtains marine wind electric field is Edc, and and DC power transmission line Voltage reference value Edc_refIt is compared, obtains discharging circuit trigger signal.Specifically, by DC power transmission line voltage measuring value EdcWith DC power transmission line voltage reference value Edc_refIt is compared by comparator, finds DC power transmission line voltage measuring value EdcHigher than DC power transmission line voltage reference value Edc_refWhen, high level signal is exported by comparator;By DC power transmission line electricity Press measured value EdcWith DC power transmission line voltage reference value Edc_refIt is compared by comparator, discovery DC power transmission line electricity Press measured value EdcNot higher than DC power transmission line voltage reference value Edc_refWhen, low level signal is exported by comparator.Wherein, The high level signal of discharging circuit trigger signal is 1, low level signal 0.By multiplication link to discharging circuit trigger signal It is handled with the control signal of discharging circuit, and the control signal Jing Guo multiplication process is carried out at clipping by amplitude limit link Reason, obtains the duty ratio of control switch device, avoids the excessively high damage for causing switching device of signal amplitude by amplitude limit link, With this in DC power transmission line voltage measuring value EdcHigher than DC power transmission line voltage reference value Edc_refWhen connect discharging circuit All switching devices of module carry out off-load work by discharging circuit submodule.
It should be noted that control switch device accounts for when catastrophe failure occurs for the net side converter station of marine wind electric field Sky is in opening state always, carries out DC power transmission line than the permanent state for being 1, the switching device of all discharging circuit submodules Off-load work;And when generic failure occurs for the net side converter station of marine wind electric field, the duty ratio of control switch device is 0~ 1 state, also, the size of duty ratio with circuit work frequency at inverse relationship, according to fault severity level and direct current system Voltage requirement can carry out combined type direct-current unloading circuit by Collaborative Control working frequency and the two parameters of duty ratio size Control method parameter designing.
The submodule pulse cooperative control method figure of combined type direct-current unloading circuit based on arrester as shown in Figure 10, For the synchronously control for guaranteeing all concatenated direct current off-load submodule, to the pass of the switching device of every group of direct current off-load submodule Break to be delayed and open delay and measure, and the control signal passed through to switching device carries out delay process.Wherein, in derailing switch When part is opened, voltage decline, it is believed that 10% time that voltage drops to submodule voltage rating is that switching device opens delay; When switching device is closed, voltage rises, it is believed that voltage rises to 90% time of submodule voltage rating as switching device pass Disconnected delay.Traverse all direct-current unloading circuit modules opens delay and shutdown delay, and delay maximum value t is opened in selectiononThe pass and Disconnected delay maximum value toff
According to the quantity of direct current off-load submodule, the pulse signal of corresponding group number is generated.It is as shown in Figure 9 based on arrester Combined type direct-current unloading circuit submodule pulse signal control and voltage measurement schematic diagram, pulse signal include output pulse Signal and feedback pulse signal.
After issuing pulse, the voltage of the switching device of voltage sensor detection direct current off-load submodule is utilized.
Before issuing pulse next time, opening for each submodule is calculated by arithmetic unit and is delayed and opens delay maximum Value toffDifference △ ton, delay maximum value t is delayed and closed by the closing that arithmetic unit calculates each submoduleonDifference △toff
According to difference △ tonWith difference △ toffIt is delayed to the pulse signal of next group of corresponding direct-current unloading circuit module Processing.
The switching device of each direct-current unloading circuit module is supplied to by every group pulse signal of delay process, it is ensured that The synchronous working of all switching devices.
Although the present invention is described in detail referring to the foregoing embodiments, those skilled in the art should manage Solution: it is still possible to modify the technical solutions described in the foregoing embodiments, or to part of technical characteristic into Row equivalent replacement;And these are modified or replaceed, various embodiments of the present invention technology that it does not separate the essence of the corresponding technical solution The spirit and scope of scheme.

Claims (10)

1. a kind of combined type direct-current unloading circuit based on arrester, which is characterized in that including being connected to DC power transmission line Off-load branch at least all the way between positive route and anode circuit;
The off-load branch includes one or more direct current off-load submodule;
The multiple direct current off-load submodule is connected between the positive route of DC power transmission line and anode circuit;
The direct current off-load submodule includes electrode input end and cathode output end, is connected between electrode input end and negative input Connect chopper circuit and arrester.
2. the combined type direct-current unloading circuit according to claim 1 based on arrester, which is characterized in that the copped wave electricity Road parallel connection buffer circuit carries out buffer protection to chopper circuit.
3. the combined type direct-current unloading circuit according to claim 2 based on arrester, which is characterized in that the buffering electricity Road includes buffering resistance-capacitance circuit, and the buffering resistance-capacitance circuit includes resistance and capacitor in series with a resistor, the resistance connection Electrode input end, the capacitor are connect with cathode output end.
4. the combined type direct-current unloading circuit according to any one of claims 1 to 3 based on arrester, feature exist In connecting by-pass switch between the electrode input end and cathode output end.
5. the combined type direct-current unloading circuit according to any one of claims 1 to 3 based on arrester, feature exist In, connect diode between the electrode input end and cathode output end, the positive electrode and negative electrode output end connection of diode, two poles The cathode of pipe is connect with electrode input end.
6. the combined type direct-current unloading circuit according to any one of claims 1 to 3 based on arrester, feature exist In the chopper circuit includes the energy dissipation device of at least one set of switching device and at least one set, switching device and energy consumer Part is connected between electrode input end and cathode output end.
7. the combined type direct-current unloading circuit according to claim 6 based on arrester, which is characterized in that the energy consumer Part includes electric power generation unloading resistance.
8. the combined type direct-current unloading circuit according to claim 6 based on arrester, which is characterized in that the derailing switch Part uses full-controlled switch pipe.
9. the combined type direct-current unloading circuit according to claim 6 based on arrester, which is characterized in that the derailing switch Part reverse parallel connection freewheeling diode.
10. the combined type direct-current unloading circuit according to claim 1 based on arrester, which is characterized in that described lightning-arrest Device includes metal oxide arrester.
CN201910251977.3A 2019-03-29 2019-03-29 A kind of combined type direct-current unloading circuit based on arrester Pending CN110071518A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110571816A (en) * 2019-07-31 2019-12-13 全球能源互联网研究院有限公司 modularized controllable unloading circuit and control method
CN111416510A (en) * 2020-03-20 2020-07-14 清华大学 Voltage equalizing circuit for high-voltage direct-current transmission hybrid converter
CN113394961A (en) * 2021-05-20 2021-09-14 清华大学 Switch submodule of composite energy consumption device and protection method thereof
CN114498560A (en) * 2020-11-13 2022-05-13 清华大学 Metal oxide arrester combined type straight string structure of power semiconductor device

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104993472A (en) * 2015-08-07 2015-10-21 国网浙江省电力公司电力科学研究院 MMC-HVDC system, DC side isolation device and isolation method
US20180183231A1 (en) * 2015-07-01 2018-06-28 Nr Electric Co., Ltd Fault current-suppressing damper topology circuit and control method thereof and converter
CN108597926A (en) * 2018-01-12 2018-09-28 山东大学 A kind of hybrid direct-current breaker topology structure and its control method
CN109274269A (en) * 2018-11-07 2019-01-25 王宇 A kind of DC chopped-wave device and control method
CN209562165U (en) * 2019-03-29 2019-10-29 清华大学 A kind of combined type direct-current unloading circuit based on arrester

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20180183231A1 (en) * 2015-07-01 2018-06-28 Nr Electric Co., Ltd Fault current-suppressing damper topology circuit and control method thereof and converter
CN104993472A (en) * 2015-08-07 2015-10-21 国网浙江省电力公司电力科学研究院 MMC-HVDC system, DC side isolation device and isolation method
CN108597926A (en) * 2018-01-12 2018-09-28 山东大学 A kind of hybrid direct-current breaker topology structure and its control method
CN109274269A (en) * 2018-11-07 2019-01-25 王宇 A kind of DC chopped-wave device and control method
CN209562165U (en) * 2019-03-29 2019-10-29 清华大学 A kind of combined type direct-current unloading circuit based on arrester

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110571816A (en) * 2019-07-31 2019-12-13 全球能源互联网研究院有限公司 modularized controllable unloading circuit and control method
CN111416510A (en) * 2020-03-20 2020-07-14 清华大学 Voltage equalizing circuit for high-voltage direct-current transmission hybrid converter
CN114498560A (en) * 2020-11-13 2022-05-13 清华大学 Metal oxide arrester combined type straight string structure of power semiconductor device
CN113394961A (en) * 2021-05-20 2021-09-14 清华大学 Switch submodule of composite energy consumption device and protection method thereof

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