CN109802380A - A kind of current limiting low-voltage control method, system and the device of D.C. high voltage transmission - Google Patents
A kind of current limiting low-voltage control method, system and the device of D.C. high voltage transmission Download PDFInfo
- Publication number
- CN109802380A CN109802380A CN201910114273.1A CN201910114273A CN109802380A CN 109802380 A CN109802380 A CN 109802380A CN 201910114273 A CN201910114273 A CN 201910114273A CN 109802380 A CN109802380 A CN 109802380A
- Authority
- CN
- China
- Prior art keywords
- voltage
- current
- curve
- slope
- talk
- 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.)
- Granted
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 current limiting low-voltage control method, system and the devices of a kind of D.C. high voltage transmission, comprising: determines starting voltage, minimum allowable voltage, maximum allowed current and minimum acceptable current according to the running parameter of HVDC transmission system；N cross-talk curve will be divided into as end point, with the UI characteristic curve that minimum allowable voltage and minimum acceptable current are another endpoint to start voltage and maximum allowed current, and sets every cross-talk slope of a curve；The sub- slope of curve > of corresponding larger voltage corresponds to the sub- slope of curve of small voltage；The coordinate value of two-end-point and every cross-talk slope of a curve are substituted into voltage-current relationship formula, the intersection coordinate value of adjacent sub- curve is obtained, to obtain the UI characteristic curve of variable slope；In system work process, when actual DC voltage is less than starting voltage, DC current instruction is limited according to gained UI characteristic curve.As it can be seen that the application avoids the continuous commutation failure of system, and it ensure that system is comparatively fast restored to operate normally.
Description
Technical field
The present invention relates to high-voltage dc transmission electrical domains, more particularly to a kind of current limiting low-voltage controlling party of D.C. high voltage transmission
Method, system and device.
Background technique
Currently, high voltage dc transmission technology failure between limitation system short-circuit levels of current, partition ac and dc systems influences
And there is greater advantage, therefore HVDC transmission system obtains extensively in power grid on the problems such as solving large capacity long distance power transmission
General application.In the prior art, switching device generallys use the thyristor of no turn-off capacity in HVDC transmission system, so high
It is a kind of common failure that commutation failure, which occurs, for pressure DC transmission system inverter side, it will lead to system dc voltage and reduces, is straight
Flow transmission power reduction, DC current increases and the adverse consequences such as the converter valve lost of life.If it is improper to control after commutation failure,
Subsequent commutation failure can also be caused, eventually lead to system dc Transmission.
There is continuous commutation failure in HVDC transmission system in order to prevent, and the prior art generallys use current limiting low-voltage control
Method: when system dc voltage drops to a designated value, the DC current instruction of system is limited, it is therefore an objective to prevent
System dc electric current increases rapidly during failure, System Reactive Power demand is reduced, to be conducive to the maintenance of system dc voltage
Or restore, and then play the role of preventing commutation failure.Specifically, existing current limiting low-voltage control method uses Linear Control side
Formula, and as shown in Figure 1 (in Fig. 1, UDC *For system dc voltage, UH *Start voltage, U for systemL *For system minimum allowable voltage,
Iord*For system dc current-order, IH *For system maximum allowed current, IL *For system minimum acceptable current).But when being
When catastrophe failure occurs for system, response is slower, causes inverter side voltage and direct current transportation power adjustment slow, for low-voltage water
Usually for the growth rate of DC current, still it is difficult to avoid that continuous commutation failure occurs for system, and after being unfavorable for failure removal
The recovery of system.
Therefore, how to provide a kind of scheme of solution above-mentioned technical problem is that those skilled in the art needs to solve at present
The problem of.
Summary of the invention
The object of the present invention is to provide current limiting low-voltage control method, system and the devices of a kind of D.C. high voltage transmission, avoid
There is a situation where continuous commutation failures for system, and ensure that system is comparatively fast restored to operate normally.
In order to solve the above technical problems, the present invention provides a kind of current limiting low-voltage control method of D.C. high voltage transmission, packet
It includes:
The starting voltage of system, minimum allowable voltage, most are determined previously according to the running parameter of HVDC transmission system
It is big to allow electric current and minimum acceptable current；
It will be an endpoint with the starting voltage and the maximum allowed current, with the minimum allowable voltage and described
Minimum acceptable current is that the UI characteristic curve of another endpoint is divided into N cross-talk curve, and sets every cross-talk slope of a curve；Its
In, the sub- slope of a curve > of corresponding larger DC voltage corresponds to the sub- slope of a curve of smaller DC voltage；N is greater than 1
Integer；
The coordinate value of two-end-point and every cross-talk slope of a curve are substituted into predeterminated voltage current relation formula, it is bent to obtain adjacent son
The intersection coordinate value of line, to finally obtain the UI characteristic curve of variable slope；
During system work, when the actual DC voltage of the system is less than the starting voltage, root
The DC current instruction of the system is limited according to the UI characteristic curve of variable slope.
Preferably, the predeterminated voltage current relation formula includes that electric current coordinate seeks relational expressionRelational expression is sought with voltage coordinateWherein, I1For it is described most
It is big to allow electric current, IN+1For the minimum acceptable current, 1 < i < N+1 and i are integer, IiFor the (i-1)-th cross-talk curve and i-th section
The corresponding current value of the intersection point of sub- curve, UiFor the corresponding voltage value of intersection point of the (i-1)-th cross-talk curve and the i-th cross-talk curve, KiFor
I-th cross-talk slope of a curve.
Preferably, after the intersection coordinate value for obtaining adjacent sub- curve, in the UI characteristic curve for finally obtaining variable slope
Before, the current limiting low-voltage control method further include:
Calculating is iterated to the intersection coordinate value using default iterative algorithm, obtains optimal intersection coordinate value；
The then characteristic process of UI for finally obtaining variable slope, comprising:
The UI characteristic curve of variable slope is obtained according to the coordinate value of two-end-point and the optimal intersection coordinate value.
Preferably, the current limiting low-voltage control method further include:
When the actual DC voltage of the system be less than the starting voltage when, control suggestion device sending expression system into
Enter the prompt information of current limiting low-voltage control.
Preferably, the suggestion device is specially indicator light or buzzer.
Preferably, voltage rating described in the voltage rating of system described in 0.7*≤starting voltage≤0.9*, 0.1* institute
State voltage rating described in voltage rating≤minimum allowable voltage≤0.2*, the rated current of system described in 0.1*≤described is most
Rated current described in small permission electric current≤0.2*, the maximum allowed current=rated current.
Preferably, N=6.
Preferably, the UI characteristic curve according to variable slope limits the DC current instruction of the system
Process, comprising:
DC current instruction relational expression is obtained according to the UI characteristic curve of variable slopeWherein, IordTo be
DC current of uniting instructs, UDCFor system dc voltage；
The actual DC voltage is substituted into corresponding DC current and instructs relational expression, the DC current for obtaining the system refers to
It enables, to control the DC current of the system according to DC current instruction.
In order to solve the above technical problems, the present invention also provides a kind of current limiting low-voltage control system of D.C. high voltage transmission,
Include:
Endpoint determining module determines the starting electricity of system for the running parameter previously according to HVDC transmission system
Pressure, minimum allowable voltage, maximum allowed current and minimum acceptable current；
Curve setting module, for that will be an endpoint, with described with the starting voltage and the maximum allowed current
Minimum allowable voltage and the minimum acceptable current are that the UI characteristic curve of another endpoint is divided into N cross-talk curve, and sets every
Cross-talk slope of a curve；Wherein, the sub- slope of a curve > of corresponding larger DC voltage corresponds to the sub- curve of smaller DC voltage
Slope；N is the integer greater than 1；
Curve acquisition module is closed for the coordinate value of two-end-point and every cross-talk slope of a curve to be substituted into predeterminated voltage electric current
It is formula, the intersection coordinate value of adjacent sub- curve is obtained, to finally obtain the UI characteristic curve of variable slope；
Current limit control module is used for during system work, when the actual DC voltage of the system is less than
When the starting voltage, the DC current instruction of the system is limited according to the UI characteristic curve of variable slope.
In order to solve the above technical problems, the present invention also provides a kind of current limiting low-voltage control device of D.C. high voltage transmission,
Include:
Memory, for storing computer program；
Processor, for realizing the current limiting low-voltage of any of the above-described kind of D.C. high voltage transmission when executing the computer program
Control method.
The present invention provides a kind of current limiting low-voltage control methods of D.C. high voltage transmission, comprising: previously according to high voltage direct current
The running parameter of transmission system determines starting voltage, minimum allowable voltage, maximum allowed current and the minimum acceptable current of system；
It will be to start voltage and maximum allowed current is an endpoint, with minimum allowable voltage and minimum acceptable current is another endpoint
UI characteristic curve be divided into N cross-talk curve, and set every cross-talk slope of a curve；Wherein, the son of corresponding larger DC voltage is bent
The slope > of line corresponds to the sub- slope of a curve of smaller DC voltage；By the coordinate value of two-end-point and every cross-talk slope of a curve generation
Enter predeterminated voltage current relation formula, the intersection coordinate value of adjacent sub- curve is obtained, to finally obtain the UI characteristic curve of variable slope；
During system work, when the actual DC voltage of system is less than starting voltage, according to the UI characteristic curve of variable slope
The DC current instruction of system is limited.
As it can be seen that the UI characteristic curve of the application includes that (son of corresponding bigger DC voltage is bent for the different sub- curve of N slope over 10
The slope of line is bigger).That is, when system dc voltage is in reduced levels, reactive power that system can be provided compared with
Few, system dc electric current should be increased at this time with more slow speed, idle when reducing commutation thus compared with the prior art
Consumption, promotes the recovery of commutation voltage；When system dc voltage reaches higher level, reactive power that system can be provided
More, system dc electric current should be increased at this time with faster speed, to promote the recovery of system transimission power, and then be avoided
There is a situation where continuous commutation failures for system, and ensure that system is comparatively fast restored to operate normally.
The present invention also provides the current limiting low-voltage control systems and device of a kind of D.C. high voltage transmission, with above-mentioned current limiting low-voltage
Control beneficial effect having the same.
Detailed description of the invention
It to describe the technical solutions in the embodiments of the present invention more clearly, below will be to institute in the prior art and embodiment
Attached drawing to be used is needed to be briefly described, it should be apparent that, the accompanying drawings in the following description is only some implementations of the invention
Example, for those of ordinary skill in the art, without creative efforts, can also obtain according to these attached drawings
Obtain other attached drawings.
Fig. 1 is that a kind of current limiting low-voltage in the prior art controls UI characteristic curve；
Fig. 2 is a kind of flow chart of the current limiting low-voltage control method of D.C. high voltage transmission provided in an embodiment of the present invention；
Fig. 3 is a kind of structural schematic diagram of HVDC transmission system model provided in an embodiment of the present invention；
Fig. 4 is that a kind of current limiting low-voltage provided in an embodiment of the present invention controls UI variable slope characteristic curve；
Fig. 5 is a kind of HVDC transmission system control structure block diagram provided in an embodiment of the present invention；
Fig. 6 (a) is a kind of use conventional low Current limited Control provided in an embodiment of the present invention in receiving end three-phase ground failure
When DC current simulation waveform；
Fig. 6 (b) is a kind of use conventional low Current limited Control provided in an embodiment of the present invention in receiving end three-phase ground failure
When DC voltage simulation waveform；
Fig. 6 (c) is a kind of use conventional low Current limited Control provided in an embodiment of the present invention in receiving end three-phase ground failure
When shutdown angle simulation waveform；
Fig. 7 (a) is that a kind of use provided in an embodiment of the present invention improves current limiting low-voltage control in receiving end three-phase ground failure
When DC current simulation waveform；
Fig. 7 (b) is that a kind of use provided in an embodiment of the present invention improves current limiting low-voltage control in receiving end three-phase ground failure
When DC voltage simulation waveform；
Fig. 7 (c) is that a kind of use provided in an embodiment of the present invention improves current limiting low-voltage control in receiving end three-phase ground failure
When shutdown angle simulation waveform；
Fig. 8 is a kind of structural representation of the current limiting low-voltage control system of D.C. high voltage transmission provided in an embodiment of the present invention
Figure.
Specific embodiment
Core of the invention is to provide current limiting low-voltage control method, system and the device of a kind of D.C. high voltage transmission, avoids
There is a situation where continuous commutation failures for system, and ensure that system is comparatively fast restored to operate normally.
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 scheme in the embodiment of the invention is clearly and completely described, 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.
Referring to figure 2., Fig. 2 is a kind of current limiting low-voltage control method of D.C. high voltage transmission provided in an embodiment of the present invention
Flow chart.
The current limiting low-voltage control method of the D.C. high voltage transmission includes:
Step S1: the starting voltage of system, minimum allowable are determined previously according to the running parameter of HVDC transmission system
Voltage, maximum allowed current and minimum acceptable current.
Specifically, referring to figure 3., Fig. 3 is a kind of knot of HVDC transmission system model provided in an embodiment of the present invention
Structure schematic diagram.HVDC transmission system includes rectification side alternating current circuit impedance Z 1, inverter side alternating current circuit impedance Z 2, AC line
The anti-ZL of roadlock, rectification side transformer T1, inverter side transformer T2, controller (αrecFor rectification side delay angle, αinvProlong for inverter side
Delay angle), rectifier and inverter.
The working principle of HVDC transmission system are as follows: the angle of flow of rectifier and inverter is adjusted come real by controller
Existing DC voltage, the generation of DC current and the transmission of power.Under normal conditions, controller is furnished with the control suitable for different condition
System strategy, such as constant dc power control, constant current control, determine hold-off angle control, current deviation control and current limiting low-voltage control control
Strategy.
For the control of the current limiting low-voltage of HVDC transmission system, the trigger condition of current limiting low-voltage control are as follows: system
Receiving end voltage, which breaks down, causes the appearance of system dc voltage to decline to a certain extent, opens when system dc voltage drops to system
When dynamic voltage, system internal controller enters current limiting low-voltage control.
Based on this, the application obtains current limiting low-voltage first and controls corresponding system most threshold voltage and be most worth electric current.Specifically,
The application determines the starting voltage and minimum allowable voltage (system most threshold voltage) of system according to the running parameter of system, and determines
The maximum allowed current and minimum acceptable current (system is most worth electric current) of system lay base to improve UI characteristic curve for the later period
Plinth.
Step S2: will be an endpoint, with minimum allowable voltage and minimum allowable to start voltage and maximum allowed current
Electric current is that the UI characteristic curve of another endpoint is divided into N cross-talk curve, and sets every cross-talk slope of a curve；Wherein, correspond to compared with
The sub- slope of a curve > of big DC voltage corresponds to the sub- slope of a curve of smaller DC voltage.
Specifically, it is contemplated that when system dc voltage is in reduced levels, the reactive power that system can be provided is less, and
When system dc electric current is in very fast growth rate, reactive power needed for system commutation is more, so working as system dc voltage
When in reduced levels, if system dc increase in current fast speed, it is insufficient to will appear the reactive power that system can be provided
For system commutation use, occur so as to cause the case where commutation failure.Conversely, when system dc voltage is in higher level,
The reactive power that system can be provided is more, so system dc electric current can be increased by faster speed at this time, it is anti-in this way
And it is capable of the recovery of promotion system transimission power.
Therefore, in order to avoid continuous commutation failure occurs for system, the application should be suitable according to the size of system dc voltage value
The growth rate of system dc electric current should be sexually revised, specifically: the growth rate > of DC current when system dc voltage is larger
The growth rate of DC current when system dc voltage is smaller.Based on this, the current limiting low-voltage control method of the application is using segmentation
Linear Control mode, specifically sets principle are as follows:
Obtain first the corresponding characteristic two-end-point of UI of current limiting low-voltage control method coordinate value (it is understood that
It is that the starting voltage and maximum allowed current of system are the characteristic endpoint of UI, the minimum allowable voltage of system and most
Small permission electric current is another characteristic endpoint of UI)；Then bigger according to system dc voltage, the increasing of system dc electric current
The control principle of long speed faster (i.e. the characteristic slope of UI is bigger), UI characteristic curve is divided into N cross-talk curve, and (N is big
In 1 integer), and the rule bigger according to the sub- slope of a curve of the bigger DC voltage of correspondence, it is that every cross-talk curve setting is oblique
Rate.
Step S3: the coordinate value of two-end-point and every cross-talk slope of a curve are substituted into predeterminated voltage current relation formula, obtained
The intersection coordinate value of adjacent sub- curve, to finally obtain the UI characteristic curve of variable slope.
It should be noted that the default of the application sets in advance, it is only necessary to which setting is primary, unless according to practical feelings
Condition needs to modify, and does not otherwise need to reset.
Specifically, the application obtain the characteristic two-end-point of UI coordinate value and every cross-talk slope of a curve after,
The intersection coordinate value for also needing to obtain adjacent sub- curve, can just finally obtain complete UI characteristic curve.So the application is set in advance
Set the coordinate value that known quantity is the characteristic two-end-point of UI and the friendship that every cross-talk slope of a curve, unknown quantity are adjacent sub- curve
The voltage-current relationship formula of coordinate value is put, then the application can incite somebody to action after the known quantity for getting voltage-current relationship formula
Known quantity substitutes into voltage-current relationship formula, obtains the unknown quantity of voltage-current relationship formula: the intersection coordinate value of adjacent sub- curve, from
And complete UI characteristic curve can be obtained (since UI characteristic curve includes Different Slope, so can be described as UI variable slope characteristic
Curve).
Step S4: oblique according to becoming when the actual DC voltage of system is less than starting voltage during system work
The UI characteristic curve of rate limits the DC current instruction of system.
Specifically, during system works, the application answers the actual DC voltage of real-time detecting system, and by its with
The starting voltage of system is made comparisons, and when the actual DC voltage of system, which is less than it, starts voltage, the application can be according to improvement
System is protected in current limiting low-voltage control afterwards, i.e., the actual DC voltage with system is obtained according to UI variable slope characteristic curve
Corresponding DC current instruction, and the DC current of system is controlled according to the instruction of this DC current, to play current limliting
Effect.
The present invention provides a kind of current limiting low-voltage control methods of D.C. high voltage transmission, comprising: previously according to high voltage direct current
The running parameter of transmission system determines starting voltage, minimum allowable voltage, maximum allowed current and the minimum acceptable current of system；
It will be to start voltage and maximum allowed current is an endpoint, with minimum allowable voltage and minimum acceptable current is another endpoint
UI characteristic curve be divided into N cross-talk curve, and set every cross-talk slope of a curve；Wherein, the son of corresponding larger DC voltage is bent
The slope > of line corresponds to the sub- slope of a curve of smaller DC voltage；By the coordinate value of two-end-point and every cross-talk slope of a curve generation
Enter predeterminated voltage current relation formula, the intersection coordinate value of adjacent sub- curve is obtained, to finally obtain the UI characteristic curve of variable slope；
During system work, when the actual DC voltage of system is less than starting voltage, according to the UI characteristic curve of variable slope
The DC current instruction of system is limited.
As it can be seen that the UI characteristic curve of the application includes that (son of corresponding bigger DC voltage is bent for the different sub- curve of N slope over 10
The slope of line is bigger).That is, when system dc voltage is in reduced levels, reactive power that system can be provided compared with
Few, system dc electric current should be increased at this time with more slow speed, idle when reducing commutation thus compared with the prior art
Consumption, promotes the recovery of commutation voltage；When system dc voltage reaches higher level, reactive power that system can be provided
More, system dc electric current should be increased at this time with faster speed, to promote the recovery of system transimission power, and then be avoided
There is a situation where continuous commutation failures for system, and ensure that system is comparatively fast restored to operate normally.
On the basis of the above embodiments:
As one kind, optionally embodiment, predeterminated voltage current relation formula include that electric current coordinate seeks relational expressionRelational expression is sought with voltage coordinateWherein, I1Permit for maximum
Perhaps electric current, IN+1For minimum acceptable current, 1 < i < N+1 and i are integer, IiFor the (i-1)-th cross-talk curve and the i-th cross-talk curve
The corresponding current value of intersection point, UiFor the corresponding voltage value of intersection point of the (i-1)-th cross-talk curve and the i-th cross-talk curve, KiFor the i-th cross-talk
Slope of a curve.
Specifically, referring to figure 4., Fig. 4 is that a kind of current limiting low-voltage provided in an embodiment of the present invention controls UI variable slope characteristic
Curve.Fig. 4 gives a kind of embodiment that UI characteristic curve is divided into 6 cross-talk curves (N=6), in Fig. 4, I1For maximum allowable electricity
Stream, IN+1For minimum acceptable current, U1For maximum permissible voltage, UN+1For minimum allowable voltage, IiRepresent the intersection point of adjacent sub- curve
Corresponding current value.
The application is by coordinate (U1, I1) and coordinate (U2, I2) between sub- curve be known as the sub- curve of paragraph 1, paragraph 1 is bent
The slope of line is known as K1, and so on, coordinate (Ui, Ii) and coordinate (Ui+1, Ii+1) between sub- curve be known as the i-th cross-talk curve,
I-th cross-talk slope of a curve is known as Ki, then IiFor the corresponding current value of intersection point of the (i-1)-th cross-talk curve and the i-th cross-talk curve, Ui
For the corresponding voltage value of intersection point of the (i-1)-th cross-talk curve and the i-th cross-talk curve.
Based on this, the voltage-current relationship formula of the application be can be set are as follows: electric current coordinate seeks relational expressionRelational expression is sought with voltage coordinateAs it can be seen that learning UI spy
The coordinate value of the two-end-point of linearity curve (includes I1、IN+1) after, relational expression can be sought according to electric current coordinate seeks adjacent son song
The corresponding current value I of the intersection point of linei.In the corresponding current value I of intersection point for learning every cross-talk slope of a curve and adjacent sub- curvei
Later, the corresponding voltage value U of intersection point that relational expression seeks adjacent sub- curve can be sought according to voltage coordinatei, to obtain
Whole UI variable slope characteristic curve.
As a kind of optionally embodiment, after the intersection coordinate value for obtaining adjacent sub- curve, become oblique finally obtaining
Before the UI characteristic curve of rate, the current limiting low-voltage control method further include:
It is iterated calculating using default iterative algorithm antinode coordinate value, obtains optimal intersection coordinate value；
Then finally obtain the characteristic process of UI of variable slope, comprising:
The UI characteristic curve of variable slope is obtained according to the coordinate value of two-end-point and optimal intersection coordinate value.
Further, it is contemplated that the intersection coordinate value for the adjacent sub- curve sought using above-mentioned voltage-current relationship formula is not
It is optimal value, so the application is optimized using iterative algorithm antinode coordinate value, is specifically sat using matlab antinode
Scale value is iterated calculating, to obtain optimal intersection coordinate value.
Correspondingly, the final UI variable slope characteristic curve of the application is obtained based on optimal intersection coordinate value, thus real
Now system is protected with more preferably current limiting low-voltage control mode.
As a kind of optionally embodiment, the current limiting low-voltage control method further include:
When the actual DC voltage of system is less than starting voltage, control suggestion device issues expression system and enters low pressure limit
The prompt information of flow control.
Further, it is known that when the actual DC voltage of system is less than starting voltage, system enters current limiting low-voltage control.
So the application can be when the actual DC voltage of system be less than starting voltage, control suggestion device issues expression system and enters
The prompt information of current limiting low-voltage control, to make related personnel by checking the prompt information of suggestion device whether to learn system
It is controlled into current limiting low-voltage.
As one kind, optionally embodiment, suggestion device are specially indicator light or buzzer.
Specifically, the suggestion device of the application can be selected but be not limited only to indicator light (the light on and off state or lamp of indicator light
Light color can be used for indicating that system enters current limiting low-voltage control) or buzzer (the buzzing situation of buzzer can be used for indicating system
Controlled into current limiting low-voltage), the application is not particularly limited herein.
As a kind of optionally embodiment, voltage rating≤starting voltage≤0.9* voltage rating of 0.7* system, 0.1*
Voltage rating≤minimum allowable voltage≤0.2* voltage rating, rated current≤minimum acceptable current≤0.2* volume of 0.1* system
Constant current, maximum allowed current=rated current.
Specifically, according to engineering experience, the starting voltage of system is generally set to 0.7~0.9 times of system nominal voltage
Between；The minimum allowable voltage of system need to be greater than the minimum voltage of system, be generally set to 0.1~0.2 times of system nominal
Between voltage；The maximum allowed current of system is usually set to equal to system nominal current；Similarly, the minimum acceptable current of system
The minimum current of system need to be greater than, be generally set between 0.1~0.2 times of system nominal current.
As a kind of optionally embodiment, N=6.
Specifically, the quantity for the sub- curve that the UI characteristic curve of the application divides is more, and system performance is higher, but corresponding
Algorithm is more complicated, so the application comprehensively considers both factors, UI characteristic curve is divided into 6 cross-talk curves.Certainly, this Shen
The characteristic division numbers of UI please can also choose other values, and the application is not particularly limited herein, according to practical feelings
Depending on condition.
As a kind of optionally embodiment, the DC current instruction of system is limited according to the UI characteristic curve of variable slope
The process of system, comprising:
DC current instruction relational expression is obtained according to the UI characteristic curve of variable slopeWherein, IordTo be
DC current of uniting instructs, UDCFor system dc voltage；
Actual DC voltage is substituted into corresponding DC current and instructs relational expression, the DC current instruction of system is obtained, to press
According to the DC current of DC current command control system.
Specifically, it was known that in UI variable slope characteristic curve every cross-talk curve two-end-point coordinate value, when system dc voltage
UDCWhen on any cross-talk curve, system dc voltage U can be sought according to the equal principle of the same sub- slope of curveDCIt is corresponding
DC current instruct Iord。
Assuming that the two-end-point coordinate of the n-th cross-talk curve is (Un, In)、(Un+1, In+1), as system dc voltage UDCN-th
When on cross-talk curve, relational expression can be obtained according to the equal principle of the same sub- slope of curve:
To deform to obtain DC current instruction relational expression to it
Based on this, the actual DC voltage that the application will test substitutes into corresponding DC current and instructs relational expression, obtains system
DC current instruction, thus according to the DC current of DC current command control system.Specifically, DC current instruction is being controlled
The action principle of device processed is as shown in Figure 5.In Fig. 5, UDC_invFor inverter side DC bus-bar voltage, UDCTo compensate stepmother at starting point
Line voltage, Iord_recFor rectification side current-order, Iord_invFor inverter side current-order, Id_recFor rectification side actual current,
Id_invFor inverter side actual current, e_recFor rectification side current error signal, e_invFor inverter side current error signal, e_γTo close
Angle of rupture error signal, βrecFor the instruction of rectification side advance angle, βinvFor the instruction of inverter side advance angle, αrecFor rectification side delay angle,
αinvFor inverter side delay angle, Δ I is offset current, and Δ γ is that deviation turns off angle, γ_ordAngle instruction, γ are turned off for inverter side_inv
Angle minimum value, β are turned off for the period in inverter sideinv_γThe advance angle instruction of hold-off angle control, β are determined for inverter sideinv-iFor inverter side
The advance angle of current control instructs.Finally, controller is by αrecAnd αinvIt is separately input into the pulse generation of rectification side and inverter side
Unit, so that impulse generating unit generates corresponding control signal.
In addition, the application can respectively to use conventional low Current limited Control and use improve current limiting low-voltage control in receiving end three
Parameter (DC current, DC voltage and shutdown angle) when phase ground fault is emulated, and imitating such as Fig. 6 (a)-Fig. 7 (c) is obtained
True figure, so that analyzing the two comparison diagram can be seen that improved current limiting low-voltage control is more excellent in performance.
Fig. 8 is please referred to, Fig. 8 is a kind of current limiting low-voltage control system of D.C. high voltage transmission provided in an embodiment of the present invention
Structural schematic diagram.
The current limiting low-voltage control system of the D.C. high voltage transmission includes:
Endpoint determining module 1 determines the starting electricity of system for the running parameter previously according to HVDC transmission system
Pressure, minimum allowable voltage, maximum allowed current and minimum acceptable current；
Curve setting module 2, for that will be an endpoint, with minimum allowable voltage to start voltage and maximum allowed current
It is divided into N cross-talk curve with minimum acceptable current for the UI characteristic curve of another endpoint, and sets every cross-talk slope of a curve；Its
In, the sub- slope of a curve > of corresponding larger DC voltage corresponds to the sub- slope of a curve of smaller DC voltage；N is greater than 1
Integer；
Curve acquisition module 3, for the coordinate value of two-end-point and every cross-talk slope of a curve to be substituted into predeterminated voltage electric current
Relational expression obtains the intersection coordinate value of adjacent sub- curve, to finally obtain the UI characteristic curve of variable slope；
Current limit control module 4, for starting voltage when the actual DC voltage of system is less than during system work
When, the DC current instruction of system is limited according to the UI characteristic curve of variable slope.
The introduction of current limiting low-voltage control system provided by the invention please refers to the embodiment of above-mentioned current limiting low-voltage control method,
Details are not described herein by the application.
The present invention also provides a kind of current limiting low-voltage control devices of D.C. high voltage transmission, comprising:
Memory, for storing computer program；
Processor, for realizing that the current limiting low-voltage of any of the above-described kind of D.C. high voltage transmission is controlled when executing computer program
Method.
The introduction of current limiting low-voltage control device provided by the invention please refers to the embodiment of above-mentioned current limiting low-voltage control method,
Details are not described herein by the application.
It should also be noted that, in the present specification, the terms "include", "comprise" or its any other variant are intended to contain
Lid non-exclusive inclusion, so that the process, method, article or equipment including a series of elements is not only wanted including those
Element, but also including other elements that are not explicitly listed, or further include for this process, method, article or equipment
Intrinsic element.In the absence of more restrictions, the element limited by sentence "including a ...", it is not excluded that
There is also other identical elements in process, method, article or equipment including the element.
The foregoing description of the disclosed embodiments enables those skilled in the art to implement or use the present invention.
Various modifications to these embodiments will be readily apparent to those skilled in the art, as defined herein
General Principle can be realized in other embodiments without departing from the spirit or scope of the present invention.Therefore, of the invention
It is not intended to be limited to the embodiments shown herein, and is to fit to and the principles and novel features disclosed herein phase one
The widest scope of cause.
Claims (10)
1. a kind of current limiting low-voltage control method of D.C. high voltage transmission characterized by comprising
Determine that the starting voltage, minimum allowable voltage, maximum of system are permitted previously according to the running parameter of HVDC transmission system
Perhaps electric current and minimum acceptable current；
It will be an endpoint, with the minimum allowable voltage and the minimum with the starting voltage and the maximum allowed current
Allowing electric current is that the UI characteristic curve of another endpoint is divided into N cross-talk curve, and sets every cross-talk slope of a curve；Wherein, right
The sub- slope of a curve > of larger DC voltage is answered to correspond to the sub- slope of a curve of smaller DC voltage；N is the integer greater than 1；
The coordinate value of two-end-point and every cross-talk slope of a curve are substituted into predeterminated voltage current relation formula, obtain adjacent sub- curve
Intersection coordinate value, to finally obtain the UI characteristic curve of variable slope；
During system work, when the actual DC voltage of the system is less than the starting voltage, according to change
The UI characteristic curve of slope limits the DC current instruction of the system.
2. the current limiting low-voltage control method of D.C. high voltage transmission as described in claim 1, which is characterized in that the predeterminated voltage
Current relation formula includes that electric current coordinate seeks relational expressionRelational expression is sought with voltage coordinateWherein, I1For the maximum allowed current, IN+1For the minimum acceptable current, 1 < i < N+1 and
I is integer, IiFor the corresponding current value of intersection point of the (i-1)-th cross-talk curve and the i-th cross-talk curve, UiFor the (i-1)-th cross-talk curve and
The corresponding voltage value of intersection point of i cross-talk curve, KiFor the i-th cross-talk slope of a curve.
3. the current limiting low-voltage control method of D.C. high voltage transmission as claimed in claim 2, which is characterized in that obtaining adjacent son
After the intersection coordinate value of curve, before finally obtaining the UI characteristic curve of variable slope, which is also wrapped
It includes:
Calculating is iterated to the intersection coordinate value using default iterative algorithm, obtains optimal intersection coordinate value；
The then characteristic process of UI for finally obtaining variable slope, comprising:
The UI characteristic curve of variable slope is obtained according to the coordinate value of two-end-point and the optimal intersection coordinate value.
4. the current limiting low-voltage control method of D.C. high voltage transmission as claimed in claim 3, which is characterized in that the current limiting low-voltage control
Method processed further include:
When the actual DC voltage of the system is less than the starting voltage, control suggestion device sending expression system enters low
Press the prompt information of Current limited Control.
5. the current limiting low-voltage control method of D.C. high voltage transmission as claimed in claim 4, which is characterized in that the suggestion device
Specially indicator light or buzzer.
6. the current limiting low-voltage control method of D.C. high voltage transmission as claimed in claim 3, which is characterized in that system described in 0.7*
Voltage rating≤starting voltage≤0.9* described in voltage rating, voltage rating≤minimum allowable voltage described in 0.1*
Voltage rating described in≤0.2*, specified electricity described in rated current≤minimum acceptable current≤0.2* of system described in 0.1*
Stream, the maximum allowed current=rated current.
7. the current limiting low-voltage control method of D.C. high voltage transmission as claimed in claim 6, which is characterized in that N=6.
8. such as the current limiting low-voltage control method of the described in any item D.C. high voltage transmissions of claim 2-7, which is characterized in that described
The process limited is instructed according to DC current of the UI characteristic curve of variable slope to the system, comprising:
DC current instruction relational expression is obtained according to the UI characteristic curve of variable slopeUn+1≤UDC≤Un, 1≤n≤N；Wherein, IordFor system dc electricity
Stream instruction, UDCFor system dc voltage；
The actual DC voltage is substituted into corresponding DC current and instructs relational expression, obtains the DC current instruction of the system,
To control the DC current of the system according to DC current instruction.
9. a kind of current limiting low-voltage control system of D.C. high voltage transmission characterized by comprising
Endpoint determining module determines the starting voltage, most of system for the running parameter previously according to HVDC transmission system
Small permission voltage, maximum allowed current and minimum acceptable current；
Curve setting module, for that will be an endpoint, with the minimum with the starting voltage and the maximum allowed current
Allow voltage and the minimum acceptable current to be divided into N cross-talk curve for the UI characteristic curve of another endpoint, and sets every cross-talk
Slope of a curve；Wherein, the sub- slope of a curve > of corresponding larger DC voltage corresponds to the oblique of the sub- curve of smaller DC voltage
Rate；N is the integer greater than 1；
Curve acquisition module, for the coordinate value of two-end-point and every cross-talk slope of a curve to be substituted into predeterminated voltage current relationship
Formula obtains the intersection coordinate value of adjacent sub- curve, to finally obtain the UI characteristic curve of variable slope；
Current limit control module, described in being less than during system work when the actual DC voltage of the system
When starting voltage, the DC current instruction of the system is limited according to the UI characteristic curve of variable slope.
10. a kind of current limiting low-voltage control device of D.C. high voltage transmission characterized by comprising
Memory, for storing computer program；
Processor, for realizing such as the described in any item high-voltage dc transmissions of claim 1-8 when executing the computer program
The current limiting low-voltage control method of electricity.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910114273.1A CN109802380B (en) | 2019-02-14 | 2019-02-14 | Low-voltage current limiting control method, system and device for high-voltage direct-current transmission |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910114273.1A CN109802380B (en) | 2019-02-14 | 2019-02-14 | Low-voltage current limiting control method, system and device for high-voltage direct-current transmission |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109802380A true CN109802380A (en) | 2019-05-24 |
| CN109802380B CN109802380B (en) | 2022-07-08 |
Family
ID=66562049
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910114273.1A Active CN109802380B (en) | 2019-02-14 | 2019-02-14 | Low-voltage current limiting control method, system and device for high-voltage direct-current transmission |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109802380B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112421591A (en) * | 2020-09-29 | 2021-02-26 | 国网福建省电力有限公司电力科学研究院 | Low-voltage current-limiting fixed value adjusting method for restraining flexible direct current near-zone three-phase short-circuit current |
| CN112636378A (en) * | 2020-12-09 | 2021-04-09 | 国家电网有限公司 | Dynamic parameter control method and system based on prediction of direct current change trend |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20090261766A1 (en) * | 2005-05-25 | 2009-10-22 | Volker Lurk | Method for controlling an electric motor fed by a constant voltage supply system |
| CN102315788A (en) * | 2010-07-06 | 2012-01-11 | 力林科技股份有限公司 | Power conversion device and overcurrent protection method thereof |
| CN104022523A (en) * | 2014-06-12 | 2014-09-03 | 国网上海市电力公司 | Voltage and current polarity control method for modulation electrode of high-voltage direct current tripolar power transmission system |
| CN104242331A (en) * | 2014-08-14 | 2014-12-24 | 国家电网公司 | Extra-high voltage direct current control system suitable for electromechanical transient simulation |
| CN108400611A (en) * | 2018-04-12 | 2018-08-14 | 国网湖南省电力公司 | The continuous commutation failure suppressing methods of HVDC based on non-linear VDCOL |
-
2019
- 2019-02-14 CN CN201910114273.1A patent/CN109802380B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20090261766A1 (en) * | 2005-05-25 | 2009-10-22 | Volker Lurk | Method for controlling an electric motor fed by a constant voltage supply system |
| CN102315788A (en) * | 2010-07-06 | 2012-01-11 | 力林科技股份有限公司 | Power conversion device and overcurrent protection method thereof |
| CN104022523A (en) * | 2014-06-12 | 2014-09-03 | 国网上海市电力公司 | Voltage and current polarity control method for modulation electrode of high-voltage direct current tripolar power transmission system |
| CN104242331A (en) * | 2014-08-14 | 2014-12-24 | 国家电网公司 | Extra-high voltage direct current control system suitable for electromechanical transient simulation |
| CN108400611A (en) * | 2018-04-12 | 2018-08-14 | 国网湖南省电力公司 | The continuous commutation failure suppressing methods of HVDC based on non-linear VDCOL |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112421591A (en) * | 2020-09-29 | 2021-02-26 | 国网福建省电力有限公司电力科学研究院 | Low-voltage current-limiting fixed value adjusting method for restraining flexible direct current near-zone three-phase short-circuit current |
| CN112421591B (en) * | 2020-09-29 | 2024-01-30 | 国网福建省电力有限公司电力科学研究院 | Low-voltage current-limiting fixed value adjusting method for inhibiting flexible direct-current near-zone three-phase short-circuit current |
| CN112636378A (en) * | 2020-12-09 | 2021-04-09 | 国家电网有限公司 | Dynamic parameter control method and system based on prediction of direct current change trend |
| CN112636378B (en) * | 2020-12-09 | 2023-10-31 | 国家电网有限公司 | Dynamic parameter control method and system based on predicted direct current change trend |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109802380B (en) | 2022-07-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP2876768A1 (en) | Method of operating a wind park | |
| CN108808718B (en) | Method for determining direct current operation range of high-voltage direct current transmission system in alternating current fault | |
| CN104242331A (en) | Extra-high voltage direct current control system suitable for electromechanical transient simulation | |
| CN113452061B (en) | Offshore wind power direct current transmission system and control method thereof | |
| CN109802380A (en) | A kind of current limiting low-voltage control method, system and the device of D.C. high voltage transmission | |
| CN103904678B (en) | The control method of high voltage direct current transmission Shift speed segmentally rate current limiting low-voltage unit | |
| CN105914751B (en) | A kind of reactive voltage control method for coordinating suitable for tetanic weak friendship serial-parallel power grid | |
| CN108964120B (en) | Low-voltage distributed photovoltaic access capacity optimization control method | |
| CN114039499A (en) | Commutation control method and device of converter, electronic equipment and readable storage medium | |
| CN114270651B (en) | Inverter reactive current control method and device | |
| CN110620396B (en) | Self-adaptive low-voltage current limiting control method for LCC direct current transmission system | |
| CN105305508B (en) | A kind of trigger angle control method during commutation failure | |
| CN107612290B (en) | Optimization control method and system for capacitor voltage sequencing frequency of current converter | |
| CN110854916A (en) | Energy balance control method and device based on user energy storage | |
| CN110380423A (en) | A kind of wind farm group Reactive-power control object priority determines method and device | |
| CN113178879B (en) | Frequency recovery control method suitable for multiple virtual synchronous machines | |
| CN114285067B (en) | Fault ride-through method and device and storage medium | |
| CN113381419B (en) | Full-power converter fault ride-through reactive power control method, system, medium and equipment | |
| AU2020102600A4 (en) | A system and method of DC voltage droop control for grid connection of offshore wind farms | |
| CN117096960B (en) | Virtual synchronous machine amplitude limiting operation control method and system considering electric quantity constraint | |
| CN114744576B (en) | Method and system for optimizing design of alternating-current transmission line to direct-current operation | |
| CN111769524B (en) | Method, device and system for adjusting grounding resistance of self-adaptive symmetrical monopole direct current power distribution network | |
| CN114362264B (en) | Method for adjusting self-adaptive active power of impedance of access line of photovoltaic inverter | |
| US20240106351A1 (en) | Multi-inverter parallel system and method for controlling grid connection of inverter | |
| CN116526538A (en) | Control method and device of direct current transmission system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |