CN114744576A - Optimization design method and system for changing alternating current transmission line into direct current operation - Google Patents
Optimization design method and system for changing alternating current transmission line into direct current operation Download PDFInfo
- Publication number
- CN114744576A CN114744576A CN202210232235.8A CN202210232235A CN114744576A CN 114744576 A CN114744576 A CN 114744576A CN 202210232235 A CN202210232235 A CN 202210232235A CN 114744576 A CN114744576 A CN 114744576A
- Authority
- CN
- China
- Prior art keywords
- direct current
- tower
- direct
- insulator
- string
- 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
- 238000000034 method Methods 0.000 title claims abstract description 43
- 230000005540 biological transmission Effects 0.000 title claims abstract description 42
- 238000013461 design Methods 0.000 title claims abstract description 13
- 238000005457 optimization Methods 0.000 title abstract description 9
- 239000012212 insulator Substances 0.000 claims abstract description 122
- 239000000725 suspension Substances 0.000 claims abstract description 18
- 239000012211 strain insulator Substances 0.000 claims abstract description 9
- 238000004364 calculation method Methods 0.000 claims description 16
- 239000002131 composite material Substances 0.000 claims description 13
- 230000015654 memory Effects 0.000 claims description 8
- 238000012937 correction Methods 0.000 claims description 7
- 238000003860 storage Methods 0.000 claims description 6
- 150000003839 salts Chemical class 0.000 claims description 3
- 238000010586 diagram Methods 0.000 description 8
- 238000004590 computer program Methods 0.000 description 7
- 238000012545 processing Methods 0.000 description 5
- 230000006870 function Effects 0.000 description 4
- 230000006978 adaptation Effects 0.000 description 2
- 238000006056 electrooxidation reaction Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 239000004576 sand Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010292 electrical insulation Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000009422 external insulation Methods 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- WABPQHHGFIMREM-UHFFFAOYSA-N lead(0) Chemical compound [Pb] WABPQHHGFIMREM-UHFFFAOYSA-N 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 230000001131 transforming effect Effects 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
- H02G7/00—Overhead installations of electric lines or cables
- H02G7/20—Spatial arrangements or dispositions of lines or cables on poles, posts or towers
- H02G7/205—Installation of electric cables, extending along a pole
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/36—Arrangements for transfer of electric power between ac networks via a high-tension dc link
-
- 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 an alternating current transmission line-to-direct current operation optimization design method and a system, wherein a direct current insulator is adopted to replace a suspension string, a jumper string and a strain insulator string of an alternating current line, a tower head gap and a strain insulator jumper gap of a linear tower are obtained through the configuration of the direct current insulator string and the air gap of the direct current line under different operation working conditions, the maximum voltage of the direct current line is adjusted to enable the tower head gap of the linear tower to be matched with the jumper gap of the strain insulator tower, the trip rate of the direct current line meets the operation requirement, the optimal maximum voltage of the direct current line, the configuration of the direct current insulator string and the air gap of the direct current line under different operation working conditions are obtained, the direct current line after alternating current is changed into direct current has the highest voltage level and the highest transmission capacity, the safe and stable operation of a flexible direct current line is met, and the reliable transmission of electric energy is realized.
Description
Technical Field
The invention relates to an alternating current transmission line-to-direct current operation optimization design method and system, and belongs to the technical field of direct current transmission.
Background
The direct current transmission is important equipment for constructing the smart power grid, compared with the traditional alternating current transmission mode, the flexible direct current transmission intelligent power grid has the advantages of large transmission capacity, small power loss, low line manufacturing cost, long transmission distance and the like, the novel power grid constructed by flexible direct current transmission has the capability of quickly controlling the operating characteristics and improving the division of a power network, has stronger technical advantages in the aspects of capacity increase, isolated island power supply, alternating current system interconnection, large-scale new energy grid connection and the like of an urban power grid, and has wide application prospect in the aspect of changing the development pattern of the power grid.
In coastal economically developed areas, the contradiction between power supply and demand is increasingly prominent, and considering that new power transmission corridors in certain areas are difficult to obtain, the cost of newly-built power transmission lines is very high, and the land acquisition cost of the power transmission corridors is far higher than the cost of the power transmission line body. In order to fully utilize the existing path channel resources and solve the extremely difficult transmission line corridor problem, an alternating current line is necessary to be changed into a direct current line, but no corresponding method exists at present.
Disclosure of Invention
The invention provides an alternating current transmission line-to-direct current operation optimization design method and system, which solve the problems disclosed in the background technology.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows:
the alternating current transmission line to direct current operation optimization design method comprises the following steps:
preliminarily determining the maximum voltage of the direct-current line according to the operating voltage of the alternating-current line;
replacing alternating-current insulators in the tangent tower lead suspension string, the strain tower lead jumper string and the strain tower lead strain string with direct-current insulators, and calculating the configuration of the direct-current insulator string according to the preliminarily determined maximum voltage of the direct-current line;
calculating the air gaps of the direct current line under different working conditions according to the preliminarily determined maximum voltage of the direct current line by utilizing the direct current discharge characteristics of the air gaps of the guide lines to the tower;
checking the tower head gap and the jumper gap of the tension tower according to the configuration of the direct-current insulator string and the air gaps of the direct-current line under different working conditions;
responding to the problems that the electric gap of the tower head of the tangent tower is insufficient or the margin is overlarge, the electric gap of the jumper gap of the tension tower is insufficient or the margin is overlarge, or the tripping rate of the direct current circuit checked according to the protection angle of the tower, the configuration of the direct current insulator string and the air gap of the direct current circuit under different working conditions does not meet the operation requirement, adjusting the maximum voltage of the direct current circuit, recalculating the air gaps of the configuration of the direct current insulator string and the direct current circuit under different working conditions until the problems that the electric gap of the tower head of the tangent tower is insufficient or the margin is overlarge, the problems that the electric gap of the jumper gap of the tension tower is insufficient or the margin is overlarge and the tripping rate of the direct current circuit meets the operation requirement, and obtaining the optimal maximum voltage of the direct current circuit, the configuration of the direct current insulator string and the air gap of the direct current circuit under different working conditions.
The formula for preliminarily determining the maximum voltage of the direct current line is as follows:
wherein, UdcIs the maximum voltage level, U, of the DC lineacIs the operating voltage of the ac line.
Replace the alternating current insulator in tangent tower wire suspension string, strain insulator tower wire jumper string and strain insulator tower wire strain insulator string for direct current insulator string, according to the DC link maximum voltage who tentatively confirms, calculate direct current insulator string's configuration, include:
and replacing alternating-current insulators in the linear tower lead suspension string, the strain tower lead jumper string and the strain tower lead strain string with direct-current insulators, and calculating the configuration of the direct-current insulator string by adopting a creepage specific distance method or a pollution voltage-resistant method according to the preliminarily determined maximum voltage of the direct-current line.
The direct-current insulator comprises a direct-current composite insulator and a direct-current disc insulator, alternating-current insulators in the tangent tower wire suspension string and the tension tower wire jumper string are replaced by the direct-current composite insulator, and alternating-current insulators in the tension tower wire tension string are replaced by the direct-current disc insulator.
The configuration of the direct current insulator string calculated by adopting a creepage ratio distance method is as follows:
direct current composite insulator: creepage distance per unit length of LcThe distance between the dry arc and the time is taken
Wherein λ is 1.0669 · ln (ESDD) +7.5127 is the creepage specific distance of the direct current line, ESDD is the equivalent salt deposit density, and U is the nominal voltage of the direct current;
d, direct-current disc insulator: effective creepage distance of single sheet is LsThen, the number of the direct current disc type insulator is obtained
The configuration of the direct current insulator string calculated by adopting a pollution pressure resistance method is as follows:
direct current composite insulator: unit length pollution flashover voltage u'50％The distance between the dry arc and the time is taken
Wherein, UmIs the maximum voltage of the DC line, K1Is a gray density correction factor, K2The correction coefficient is uneven, n is a standard deviation multiple, and sigma is the standard deviation of the pollution flashover voltage of the direct current insulator;
d, direct-current disc insulator: single chip pollution flashover voltage of u50％In time, the number of the direct current disc type insulator is taken
Adjusting the maximum voltage of the DC line, comprising:
if the problem of insufficient electrical clearance exists in the tower head clearance of the linear tower, the problem of insufficient electrical clearance exists in the jumper clearance of the strain tower, or the tripping rate of the direct current line does not meet the operation requirement, reducing the maximum voltage of the direct current line according to a preset step length;
and if the problem of overlarge electric clearance margin in the tower head clearance of the linear tower or the problem of overlarge electric clearance margin in the jumper clearance of the strain tower exists, the maximum voltage of the direct-current line is increased according to the preset step length.
Alternating current transmission line changes direct current operation optimal design system includes:
a preliminary maximum voltage determination module: preliminarily determining the maximum voltage of the direct-current line according to the operating voltage of the alternating-current line;
a configuration calculation module: replacing alternating-current insulators in the tangent tower lead suspension string, the tension tower lead jumper string and the tension tower lead tension string with direct-current insulators, and calculating the configuration of a direct-current insulator string according to the preliminarily determined maximum voltage of a direct-current line;
an air gap calculation module: calculating the air gaps of the direct current line under different working conditions according to the preliminarily determined maximum voltage of the direct current line by utilizing the direct current discharge characteristics of the air gaps of the guide lines to the tower;
the tower head gap and jumper gap calculation module comprises: checking the tower head gap and the jumper gap of the tension tower according to the configuration of the direct-current insulator string and the air gaps of the direct-current line under different working conditions;
the determining module: responding to the problems of insufficient electric clearance or overlarge margin existing in the tower head clearance of the tangent tower, insufficient electric clearance or overlarge margin existing in the jumper clearance of the strain tower, or the tripping rate of the direct current line checked according to the protection angle of the tower, the configuration of the direct current insulator string and the air clearance of the direct current line under different working conditions does not meet the operation requirement, adjusting the maximum voltage of the direct current line, switching to a configuration calculation module and an air gap calculation module, recalculating the air gaps of the direct current insulator string configuration and the direct current line under different working conditions until the gap of the tower head of the linear tower does not have the problem of insufficient electric gap or overlarge margin, the gap of the jumper wire of the strain tower does not have the problem of insufficient electric gap or overlarge margin, and the trip rate of the direct current line meets the operation requirement, so that the optimal maximum voltage of the direct current line, the optimal direct current insulator string configuration and the optimal air gaps of the direct current line under different working conditions are obtained.
The determining module comprises a voltage adjusting module used for adjusting the maximum voltage of the direct current line;
the voltage regulation module includes:
a first adjustment module: if the problem of insufficient electrical clearance exists in the tower head clearance of the linear tower, the problem of insufficient electrical clearance exists in the jumper clearance of the strain tower, or the tripping rate of the direct current line does not meet the operation requirement, reducing the maximum voltage of the direct current line according to a preset step length;
a second adjustment module: and if the problem that the electric clearance margin is too large exists in the tower head clearance of the linear tower or the electric clearance margin is too large in the jumper clearance of the strain tower, the maximum voltage of the direct current line is increased according to the preset step length.
A computer readable storage medium storing one or more programs, the one or more programs comprising instructions, which when executed by a computing device, cause the computing device to perform an alternating current transmission line-to-direct current operation optimization design method.
A computing device comprising one or more processors, one or more memories, and one or more programs stored in the one or more memories and configured to be executed by the one or more processors, the one or more programs including instructions for performing any of the alternating current transmission line-to-direct current operation optimization design methods.
The invention achieves the following beneficial effects: the invention adopts the direct current insulator to replace the overhang string, the jumper string and the strain insulator string of the alternating current circuit, obtains the tower head gap of the linear tower and the jumper gap of the strain tower through the configuration of the direct current insulator string and the air gap of the direct current circuit under different working conditions, adapts the tower head gap of the linear tower and the jumper gap of the strain tower by adjusting the maximum voltage of the direct current circuit, ensures that the direct current circuit after alternating current is changed into direct current has the highest voltage grade and the highest transmission capacity by meeting the operation requirement of the trip rate of the direct current circuit and obtaining the optimal maximum voltage of the direct current circuit, the configuration of the direct current insulator string and the air gap of the direct current circuit under different working conditions, and simultaneously meets the safe and stable operation of the flexible direct current circuit and realizes the reliable transmission of electric energy.
Drawings
FIG. 1 is a tower for changing an AC transmission line into DC operation;
FIG. 2 is a flow chart of the present invention.
Detailed Description
The invention is further described below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.
As shown in fig. 1, a tower for changing the current ac transmission line into the dc transmission line comprises a tangent tower, a tension tower, a wire suspension string, an electrical gap, a jumper, a wire jumper string and a wire tension string. In order to fully utilize the existing power transmission equipment, an alternating current power transmission line is changed into a direct current power transmission line on the premise of not transforming the existing tangent tower and tension tower of the alternating current line and not replacing a lead.
Specifically, as shown in fig. 2, the method for optimally designing the alternating current transmission line to direct current operation includes:
step 1, preliminarily determining the maximum voltage of a direct current line according to the running voltage of the alternating current line;
replacing alternating-current insulators in the tangent tower lead suspension string, the strain tower lead jumper string and the strain tower lead strain string with direct-current insulators, and calculating the configuration of the direct-current insulator string according to the preliminarily determined maximum voltage of the direct-current line;
step 3, calculating the air gaps of the direct current line under different working conditions according to the preliminarily determined maximum voltage of the direct current line by utilizing the direct current discharge characteristics of the air gaps of the guide lines to the tower;
step 4, checking the tower head clearance of the tangent tower and the jumper clearance of the strain tower according to the configuration of the direct current insulator string and the air clearance of the direct current line under different working conditions;
step 5, responding to the problems that the electric clearance is insufficient or the margin is too large in the tower head clearance of the tangent tower and the electric clearance is insufficient and too large in the jumper clearance of the strain tower, or the trip rate of the direct current line checked according to the protection angle of the tower, the configuration of the direct current insulator string and the air clearance of the direct current line under different working conditions does not meet the operation requirement, adjusting the maximum voltage of the direct current line, and turning to the step 2; if the problem that the electric clearance is insufficient or the margin is too large does not exist in the tower head clearance of the linear tower, the problem that the electric clearance is insufficient or the margin is too large does not exist in the jumper clearance of the strain tower, and the tripping rate of the direct current line meets the operation requirement, the optimal maximum voltage of the direct current line, the optimal configuration of the direct current insulator string and the optimal air clearance of the direct current line under different operation working conditions are obtained.
The method comprises the steps of replacing a suspension string, a jumper string and a strain insulator string of an alternating current circuit by adopting a direct current insulator, obtaining a tower head gap of a linear tower and a jumper gap of the strain tower through the configuration of the direct current insulator string and the air gap of the direct current circuit under different working conditions, adapting the tower head gap of the linear tower and the jumper gap of the strain tower by adjusting the maximum voltage of the direct current circuit, enabling the trip rate of the direct current circuit to meet the operation requirement, obtaining the optimal maximum voltage of the direct current circuit, the configuration of the direct current insulator string and the air gap of the direct current circuit under different working conditions, enabling the direct current circuit after alternating current is changed into direct current to have the highest possible voltage level and the highest possible transmission capacity, simultaneously meeting the safe and stable operation of a flexible direct current circuit, and realizing the reliable transmission of electric energy.
Before the method is carried out in real time, the target of transformation needs to be known, namely, the type of a lead of an original alternating current line, the sizes of tower heads of a tangent tower and a strain tower, the structural height of an insulator and the air gap of the tower head need to be obtained.
According to the operating voltage of the alternating current line, the maximum voltage of the direct current line is preliminarily determined, and a specific calculation formula can be as follows:
wherein, UdcIs the maximum voltage level, U, of the DC lineacIs the operating voltage of the ac line.
Unlike alternating current transmission lines, high voltage direct current lines are more prone to electrochemical corrosion than alternating current voltages in humid environments. The electrochemical corrosion of the insulator affects the electrical insulation strength and mechanical endurance performance of the insulator string, resulting in the reduction of the filth withstand voltage and mechanical failure load. The original alternating current insulator is difficult to satisfy the long-term safe and stable operation of a direct current line, so that alternating current insulators in a tangent tower wire suspension string, a tension tower wire jumper string and a tension tower wire tension string need to be replaced by the direct current insulator.
The direct current insulator generally comprises a direct current composite insulator and a direct current disc insulator, in order to improve the direct current operating voltage of an alternating current line as much as possible, the composite insulator is utilized to have excellent pollution flashover resistance, the alternating current insulators in a tangent tower lead suspension string and a tension tower lead jumper string are replaced by the direct current composite insulator, the alternating current insulators in the tension tower lead tension string are replaced by the direct current disc insulator, and then the configuration of the direct current string insulator is calculated by adopting a creepage specific distance method or a pollution voltage resistance method.
According to the preliminarily determined maximum voltage of the direct-current line, calculating the configuration of the direct-current insulator string by adopting a creepage ratio distance method:
defining a nominal direct current voltage as U, equivalent salt deposit density as ESDD, and creepage distance of a direct current line as lambda being 1.0669 · ln (ESDD) + 7.5127;
direct current composite insulator: creepage distance per unit length of LcThe distance between the dry arc and the time is taken
D, direct-current disc insulator: effective creepage distance of single plate is LsIn time, the number of the direct current disc type insulator is taken
Calculating the configuration of the direct current insulator string by adopting a pollution pressure-resistant method:
defining the maximum voltage U of the DC linemThe ash density correction coefficient is K1The non-uniformity correction coefficient is K2The standard deviation multiple is n, and the standard deviation sigma of the pollution flashover voltage of the direct-current insulator is calculated;
direct current composite insulator: unit length pollution flashover voltage u'50％The distance between the dry arc and the time is taken
D, direct-current disc insulator: monolithic sewageFlash voltage of u50％Then, the number of the direct current disc type insulator is obtained
According to the air gap direct current discharge characteristics of the conductor to the tower, the air gap of the direct current line under different working conditions can be calculated, the air gap of the direct current line under working voltage, operation, thunder and live working conditions comprises the following specific processes:
according to the rated DC voltage UNAir density coefficient k1Humidity correction coefficient k2Safety factor k3Relative standard deviation sigma of air gap DC discharge voltagesAnd acquiring 50% discharge voltage of the wire pair in the air gap of the tower
Calculating the working voltage air gap according to the air gap direct current discharge characteristic;
according to the highest working voltage UmAir density coefficient k1Humidity correction coefficient k2Over-pressure factor k of operation4Coefficient of variation σ 'of air gap under operating overpressure'sAnd obtaining the discharge voltage of the lead wire to the positive pole of the tower air gap under 50% of the operating condition
Calculating an over-voltage operating air gap according to the positive polarity operation impulse discharge voltage discharge characteristic of the wire to the tower air gap;
under the working condition of excessive lightning pressure, air gap positive polarity lightning impulse 50% discharge voltage U'50％50% lightning impulse discharge voltage U with insulator string50％Is matched with (the gap is matched according to the insulation length required by 0 grade of dirt), U'50％＝80％·U50％；
In the live working gap, the standard deviation multiple is changed from 2 to 3 by excessive pressure, namely the pressure resistance guarantee rate is 99.86 percent, in consideration of the safety of live working personnel.
And acquiring the tower head gap and the jumper gap of the strain tower under the condition of calculating the configuration of the direct-current insulator string and the air gap of the direct-current line under different working conditions.
Judging whether the gap between the tower heads of the linear towers and the gap between the jumper wires of the strain tower have the problem of insufficient electrical clearance or overlarge margin, if the gap between the tower heads of the linear towers has the problem of insufficient electrical clearance or the gap between the jumper wires of the strain tower has the problem of insufficient electrical clearance, reducing the maximum voltage of the direct-current circuit according to a preset step length (generally 5kV or 10kV), turning to the step 2, if the gap between the tower heads of the linear towers has the problem of overlarge electrical clearance margin or the gap between the jumper wires of the strain tower has the problem of overlarge electrical clearance, increasing the maximum voltage of the direct-current circuit according to the preset step length (generally 5kV or 10kV), turning to the step 2, otherwise, indicating clearance adaptation.
And under the condition of gap adaptation, checking the trip rate of the direct current line according to a protection angle of the tower, the configuration of the direct current insulator string and the air gap of the direct current line under different working conditions, if the trip rate of the direct current line does not meet the operation requirement, reducing the maximum voltage of the direct current line according to a preset step length (generally 5kV or 10kV), and turning to the step 2, if the trip rate of the direct current line does not meet the operation requirement, taking the current maximum voltage of the direct current line, the configuration of the direct current insulator string and the air gap of the direct current line under different working conditions as an optimal result, and completing the design of the key technical parameters of alternating current to direct current.
Based on the method, the method is realized, the existing tower head electric clearance of the existing tangent tower and the existing strain tower is utilized, the voltage grade selection, the external insulation configuration and the electric clearance design of the direct current line are carried out, the lead suspension string, the lead strain string and the lead jumper string are replaced, and the jumper is remanufactured, so that the direct current transformed line simultaneously meets the electric clearance requirements of working voltage, over-large operation voltage and over-large lightning voltage.
Based on the same technical scheme, the invention also discloses a software system of the method, and the alternating current transmission line is changed into a direct current operation optimization design system, which comprises the following steps:
a preliminary maximum voltage determination module: and preliminarily determining the maximum voltage of the direct-current line according to the operating voltage of the alternating-current line.
A configuration calculation module: replacing alternating-current insulators in the tangent tower lead suspension string, the tension tower lead jumper string and the tension tower lead tension string with direct-current insulators, and calculating the configuration of a direct-current insulator string according to the preliminarily determined maximum voltage of a direct-current line;
an air gap calculation module: calculating the air gaps of the direct current line under different working conditions according to the preliminarily determined maximum voltage of the direct current line by utilizing the direct current discharge characteristics of the air gaps of the guide lines to the tower;
the tower head clearance and jumper wire clearance calculation module: checking the tower head gap and the jumper gap of the tension tower according to the configuration of the direct-current insulator string and the air gaps of the direct-current line under different working conditions;
a determination module: responding to the problems of insufficient electric clearance or overlarge margin existing in the tower head clearance of the tangent tower and insufficient and overlarge electric clearance existing in the jumper clearance of the strain tower, or the tripping rate of the direct current line checked according to the protection angle of the tower, the configuration of the direct current insulator string and the air clearance of the direct current line under different working conditions does not meet the operation requirement, adjusting the maximum voltage of the direct-current line, switching to a configuration calculation module and an air gap calculation module, recalculating the air gaps of the direct-current insulator string configuration and the direct-current line under different operation conditions until the tower head gap of the tangent tower does not have the problem of insufficient electric gap or overlarge margin, the jumper gap of the strain tower does not have the problem of insufficient electric gap or overlarge margin, and the tripping rate of the direct-current line meets the operation requirements, and obtaining the optimal maximum voltage of the direct-current line, the optimal direct-current insulator string configuration and the optimal air gaps of the direct-current line under different operation conditions.
The determining module comprises a voltage adjusting module used for adjusting the maximum voltage of the direct current line;
the voltage regulation module includes:
a first adjustment module: if the problem of insufficient electrical clearance exists in the tower head clearance of the linear tower, the problem of insufficient electrical clearance exists in the jumper clearance of the strain tower, or the tripping rate of the direct current line does not meet the operation requirement, reducing the maximum voltage of the direct current line according to a preset step length;
a second adjustment module: and if the problem that the electric clearance margin is too large exists in the tower head clearance of the linear tower or the electric clearance margin is too large in the jumper clearance of the strain tower, the maximum voltage of the direct current line is increased according to the preset step length.
The data processing flow of each module in the dc transmission line-to-dc system is consistent with that of the method, and the description is not repeated here.
Based on the same technical scheme, the invention also discloses a computer-readable storage medium storing one or more programs, wherein the one or more programs comprise instructions, and when the instructions are executed by computing equipment, the computing equipment executes the method for optimally designing the direct current operation of the alternating current transmission line.
Based on the same technical solution, the invention also discloses a computing device, which comprises one or more processors, one or more memories and one or more programs, wherein the one or more programs are stored in the one or more memories and configured to be executed by the one or more processors, and the one or more programs comprise instructions for executing the method for optimizing and designing the operation of the alternating current transmission line to the direct current operation.
As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
The present invention is not limited to the above embodiments, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention are included in the scope of the claims of the present invention which are filed as the application.
Claims (10)
1. The method for optimally designing the change of the alternating current transmission line into the direct current operation is characterized by comprising the following steps of:
preliminarily determining the maximum voltage of the direct-current line according to the operating voltage of the alternating-current line;
replacing alternating-current insulators in the tangent tower lead suspension string, the tension tower lead jumper string and the tension tower lead tension string with direct-current insulators, and calculating the configuration of a direct-current insulator string according to the preliminarily determined maximum voltage of a direct-current line;
calculating the air gaps of the direct current line under different working conditions according to the preliminarily determined maximum voltage of the direct current line by utilizing the direct current discharge characteristics of the air gaps of the guide lines to the tower;
checking a tower head gap and a jumper gap of the tension tower according to the configuration of the direct current insulator string and the air gaps of the direct current line under different working conditions;
responding to the problems that the electric gap is insufficient or the margin is overlarge in the tower head gap of the tangent tower, the electric gap is insufficient or the margin is overlarge in the jumper gap of the tension tower, or the trip rate of the direct current circuit checked according to the protection angle of the tower, the configuration of the direct current insulator string and the air gap of the direct current circuit under different working conditions does not meet the operation requirement, adjusting the maximum voltage of the direct current circuit, recalculating the air gap of the configuration of the direct current insulator string and the direct current circuit under different working conditions until the problems that the electric gap is insufficient or the margin is overlarge in the tower head gap of the tangent tower, the problems that the electric gap is insufficient or the margin is overlarge in the jumper gap of the tension tower, and the trip rate of the direct current circuit meets the operation requirement, and obtaining the optimal maximum voltage of the direct current circuit, the configuration of the direct current insulator string and the air gap of the direct current circuit under different working conditions.
2. The method according to claim 1, wherein the formula for preliminarily determining the maximum voltage of the dc link is:
wherein, UdcMaximum voltage class, U, of the DC lineacIs the operating voltage of the ac line.
3. The method according to claim 1, wherein the method includes replacing ac insulators in the tangent tower lead suspension string, the strain tower lead jumper string, and the strain tower lead strain insulator string with dc insulator strings, and calculating the configuration of the dc insulator strings according to the preliminarily determined maximum voltage of the dc line, and includes:
and replacing alternating-current insulators in the linear tower lead suspension string, the strain tower lead jumper string and the strain tower lead strain string with direct-current insulators, and calculating the configuration of the direct-current insulator string by adopting a creepage specific distance method or a pollution voltage-resistant method according to the preliminarily determined maximum voltage of the direct-current line.
4. The method according to claim 3, wherein the DC insulator comprises a DC composite insulator and a DC disc insulator, the AC insulator in the tangent tower wire suspension string and the tension tower wire jumper string is replaced by the DC composite insulator, and the AC insulator in the tension tower wire tension string is replaced by the DC disc insulator.
5. The method for optimally designing the direct current operation of the alternating current transmission line according to claim 4, wherein the configuration of the direct current insulator string calculated by adopting a creepage ratio distance method is as follows:
direct current composite insulator: creepage distance per unit length of LcThe distance between the dry arc and the time is taken
Wherein λ is 1.0669 · ln (ESDD) +7.5127 is the creepage specific distance of the direct current line, ESDD is the equivalent salt deposit density, and U is the nominal voltage of the direct current;
d, direct-current disc insulator: effective creepage distance of single sheet is LsIn time, the number of the direct current disc type insulator is taken
The configuration of the direct-current insulator string calculated by adopting a pollution-voltage-withstanding method is as follows:
direct current composite insulator: unit length pollution flashover voltage u'50％Time, dry arc distance
Wherein, UmIs the maximum voltage of the DC line, K1Is ash densityCorrection factor, K2The correction coefficient is uneven, n is a standard deviation multiple, and sigma is the standard deviation of the pollution flashover voltage of the direct current insulator;
d, direct-current disc insulator: single chip pollution flashover voltage of u50％Then, the number of the direct current disc type insulator is obtained
6. The method according to claim 1, wherein the adjusting of the maximum voltage of the dc line comprises:
if the problem of insufficient electrical clearance exists in the tower head clearance of the linear tower, the problem of insufficient electrical clearance exists in the jumper clearance of the strain tower, or the tripping rate of the direct current line does not meet the operation requirement, reducing the maximum voltage of the direct current line according to a preset step length;
and if the problem that the electric clearance margin is too large exists in the tower head clearance of the linear tower or the electric clearance margin is too large in the jumper clearance of the strain tower, the maximum voltage of the direct current line is increased according to the preset step length.
7. Alternating current transmission line changes direct current operation optimal design system, its characterized in that includes:
a preliminary maximum voltage determination module: preliminarily determining the maximum voltage of the direct-current line according to the operating voltage of the alternating-current line;
a configuration calculation module: replacing alternating-current insulators in the tangent tower lead suspension string, the tension tower lead jumper string and the tension tower lead tension string with direct-current insulators, and calculating the configuration of a direct-current insulator string according to the preliminarily determined maximum voltage of a direct-current line;
an air gap calculation module: calculating the air gaps of the direct current line under different working conditions according to the preliminarily determined maximum voltage of the direct current line by utilizing the direct current discharge characteristics of the air gaps of the guide lines to the tower;
the tower head gap and jumper gap calculation module comprises: checking the tower head gap and the jumper gap of the tension tower according to the configuration of the direct-current insulator string and the air gaps of the direct-current line under different working conditions;
a determination module: responding to the problems of insufficient electric clearance or overlarge margin existing in the tower head clearance of the tangent tower, insufficient electric clearance or overlarge margin existing in the jumper clearance of the strain tower, or the tripping rate of the direct current line checked according to the protection angle of the tower, the configuration of the direct current insulator string and the air clearance of the direct current line under different working conditions does not meet the operation requirement, adjusting the maximum voltage of the direct current line, switching to a configuration calculation module and an air gap calculation module, recalculating the air gaps of the direct current insulator string configuration and the direct current line under different working conditions until the gap of the tower head of the linear tower does not have the problem of insufficient electric gap or overlarge margin, the gap of the jumper wire of the strain tower does not have the problem of insufficient electric gap or overlarge margin, and the trip rate of the direct current line meets the operation requirement, so that the optimal maximum voltage of the direct current line, the optimal direct current insulator string configuration and the optimal air gaps of the direct current line under different working conditions are obtained.
8. The system of claim 7, wherein the determining module comprises a voltage adjusting module for adjusting a maximum voltage of the dc link;
the voltage regulation module includes:
a first adjustment module: if the problem of insufficient electrical clearance exists in the tower head clearance of the linear tower, the problem of insufficient electrical clearance exists in the jumper clearance of the strain tower, or the tripping rate of the direct current line does not meet the operation requirement, reducing the maximum voltage of the direct current line according to a preset step length;
a second adjustment module: and if the problem that the electric clearance margin is too large exists in the tower head clearance of the linear tower or the electric clearance margin is too large in the jumper clearance of the strain tower, the maximum voltage of the direct current line is increased according to the preset step length.
9. A computer readable storage medium storing one or more programs, the one or more programs comprising instructions, which when executed by a computing device, cause the computing device to perform any of the methods of claims 1-6.
10. A computing device, comprising:
one or more processors, one or more memories, and one or more programs stored in the one or more memories and configured to be executed by the one or more processors, the one or more programs including instructions for performing any of the methods of claims 1-6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210232235.8A CN114744576B (en) | 2022-03-09 | Method and system for optimizing design of alternating-current transmission line to direct-current operation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210232235.8A CN114744576B (en) | 2022-03-09 | Method and system for optimizing design of alternating-current transmission line to direct-current operation |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114744576A true CN114744576A (en) | 2022-07-12 |
| CN114744576B CN114744576B (en) | 2024-05-14 |
Family
ID=
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1118260A (en) * | 1997-04-30 | 1999-01-22 | Furukawa Electric Co Ltd:The | Power transmission line |
| WO2001086772A1 (en) * | 2000-05-12 | 2001-11-15 | Tarczy Peter | Apparatus for elevated suspension of an overhead electrical conductor and overhead conductor suspension structure |
| CN101540487A (en) * | 2009-04-30 | 2009-09-23 | 南方电网技术研究中心 | Configuration method of high-voltage transmission line insulator |
| KR101292856B1 (en) * | 2012-04-13 | 2013-08-02 | 엘에스산전 주식회사 | Method for designing insulation level of hvdc system |
| CN103972919A (en) * | 2014-05-14 | 2014-08-06 | 国网上海市电力公司 | Method for selecting direct current rated voltage after change of alternating current transmission line into tripolar direct current transmission line |
| CN104967109A (en) * | 2015-07-15 | 2015-10-07 | 国家电网公司 | Determination method of rated power after reconstructing alternating current line into direct current line and system |
| CN105740516A (en) * | 2016-01-25 | 2016-07-06 | 中国电力工程顾问集团西南电力设计院有限公司 | Method for determining electric insulation reliability of power transmission line |
| CN113836856A (en) * | 2021-10-21 | 2021-12-24 | 中国电力工程顾问集团西北电力设计院有限公司 | 750kV one-tower double-loop ultrahigh tower lightning protection design method |
| KR102343417B1 (en) * | 2021-06-09 | 2021-12-27 | 주식회사 테라기술단 | Supporting Equipment For Over-head Distribution Lines |
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1118260A (en) * | 1997-04-30 | 1999-01-22 | Furukawa Electric Co Ltd:The | Power transmission line |
| WO2001086772A1 (en) * | 2000-05-12 | 2001-11-15 | Tarczy Peter | Apparatus for elevated suspension of an overhead electrical conductor and overhead conductor suspension structure |
| CN101540487A (en) * | 2009-04-30 | 2009-09-23 | 南方电网技术研究中心 | Configuration method of high-voltage transmission line insulator |
| KR101292856B1 (en) * | 2012-04-13 | 2013-08-02 | 엘에스산전 주식회사 | Method for designing insulation level of hvdc system |
| CN103972919A (en) * | 2014-05-14 | 2014-08-06 | 国网上海市电力公司 | Method for selecting direct current rated voltage after change of alternating current transmission line into tripolar direct current transmission line |
| CN104967109A (en) * | 2015-07-15 | 2015-10-07 | 国家电网公司 | Determination method of rated power after reconstructing alternating current line into direct current line and system |
| CN105740516A (en) * | 2016-01-25 | 2016-07-06 | 中国电力工程顾问集团西南电力设计院有限公司 | Method for determining electric insulation reliability of power transmission line |
| KR102343417B1 (en) * | 2021-06-09 | 2021-12-27 | 주식회사 테라기술단 | Supporting Equipment For Over-head Distribution Lines |
| CN113836856A (en) * | 2021-10-21 | 2021-12-24 | 中国电力工程顾问集团西北电力设计院有限公司 | 750kV one-tower double-loop ultrahigh tower lightning protection design method |
Non-Patent Citations (3)
| Title |
|---|
| 吴建坤;曹炜;杨文清;: "交流输电线路改造为直流输电线路的技术综述", 华东电力, no. 04, 24 April 2013 (2013-04-24), pages 0737 - 0740 * |
| 吴建坤等: ""交流输电线路改造为直流输电线路的技术综述"", 《华东电力》, vol. 41, no. 4, pages 737 - 740 * |
| 戴朝波，彭傊: ""交流线路改直流运行研究"", 《智能电网》, vol. 4, no. 11, pages 1141 - 1148 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112467740B (en) | Lightning early warning-based important power transmission channel lightning stroke active protection method | |
| CN107317294B (en) | Method and system for insulation protection of extra-high voltage half-wavelength power transmission line based on power fluctuation | |
| CN111025097A (en) | Intelligent method for evaluating leakage current difference factor of XLPE cable after aging | |
| CN111123028A (en) | Active low-voltage distribution network fault location optimization method based on hierarchical model | |
| WO2015096519A1 (en) | Method for paralleling power grid black-start subsystem having external support | |
| CN108736511A (en) | It is a kind of through the soft wind-powered electricity generation transmitting system fault traversing control method and system directly collected | |
| CN103972897A (en) | Method for determining control range of operation voltage of 500kV bus of extra-high voltage alternating-current transformer substation | |
| CN106203742B (en) | Power grid equipment energy-saving evaluation and type selection method based on energy-saving return rate | |
| CN106295176B (en) | A method of assessment transformer short-circuit and damage risk | |
| CN114744576B (en) | Method and system for optimizing design of alternating-current transmission line to direct-current operation | |
| CN114744576A (en) | Optimization design method and system for changing alternating current transmission line into direct current operation | |
| CN106229959B (en) | Overvoltage suppression method for extra-high voltage direct current transmission line | |
| CN110307898B (en) | Method and device for calculating noise below high-voltage direct-current line by adopting molded lines | |
| CN109829596B (en) | Transformer fault rate evaluation method based on historical fault data of power distribution network | |
| CN110458334A (en) | A kind of limiting short-circuit current method of operation aid decision-making method | |
| CN113902219A (en) | Analysis method of main transformer load influence factor analysis model | |
| CN110417023B (en) | Configuration and operation control method for distributed static series compensator | |
| CN103094906A (en) | 750 kV magnetic-control type controllable highly resistance circuit based on compensation winding energy-getting excitation | |
| CN113346493A (en) | Optimal scheduling method for power distribution network terminal power quality management cluster system | |
| CN203070806U (en) | Device for reducing AC submarine power cable armor loss | |
| CN113890009B (en) | Optimized matching method for outgoing line of 220kV transformer substation | |
| CN111181171A (en) | Reactive power compensation device | |
| CN113410862B (en) | Commutation failure prevention control method considering multi-feed-in direct current coupling effect | |
| CN105449648B (en) | A kind of optimization method of UHVDC Transmission Lines traveling-wave protection characteristic quantity floating threshold | |
| CN115102152B (en) | Direct current system response method and system based on lightning early warning |
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 |