CN103630812B - Electric field analysis-based super high-voltage direct current transmission converter valve fault diagnosis method - Google Patents
Electric field analysis-based super high-voltage direct current transmission converter valve fault diagnosis method Download PDFInfo
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- CN103630812B CN103630812B CN201310634647.5A CN201310634647A CN103630812B CN 103630812 B CN103630812 B CN 103630812B CN 201310634647 A CN201310634647 A CN 201310634647A CN 103630812 B CN103630812 B CN 103630812B
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Abstract
The invention relates to an electric field analysis-based super high-voltage direct current transmission converter valve fault diagnosis method, comprising the steps of extracting structural parameters according to an actual model of a converter valve; establishing an electric field computing model of the converter valve according to the extracted structural parameters; selecting the electric field type to be applied to the electric field computing model of the converter valve and setting corresponding excitation and boundary conditions; performing electric field analysis on the electric field computing model of the converter valve, judging whether an insulation fault occurs, and positioning the fault occurring position. From the property of the electric field, the electric field computing model capable of reflecting the insulation characteristics of the converter valve can be accurately established, and the reasonable use of the computer resource is ensured; the insulation features of the insulation structure can be analyzed according to the actual condition under different work conditions, the position easily subjected to local discharging is judged, and the fault occurring position is accurately positioned.
Description
Technical field
The invention belongs to electric and electronic technical field, it is related to a kind of extra-high voltage direct-current transmission converter valve based on analysis of electric field
Method for diagnosing faults.
Background technology
D.C. high voltage transmission (high voltage dc transmission, hvdc) have suitable distance, high-power,
The advantage of trans-regional transmission of electricity, since over half a century, high voltage dc transmission technology has obtained quick development.China will ±
The electric pressure of 800kv definition extra-high voltage direct-current voltage, the DC transmission engineering of China's planning construction up to more than 40, wherein
Extra-high voltage direct-current transmission (ultra high voltage dc transmission, uhvdc) engineering is more than 15.
Converter valve, as the nucleus equipment of extra-high voltage DC transmission system, is the main device realizing the conversion of alternating current-direct current electric energy
Part, is also the equipment of most expensive in extra-high voltage DC transmission system simultaneously, has technical difficulty height, integrated level is big, stability will
The features such as ask high, interdisciplinary, contains Power Electronic Technique, High-Voltage Technology, cooling technology, electric insulation technology, all presses skill
Multiple subject such as art, control technology.In the domestic at present research field in extra-high voltage direct-current transmission, defeated with regard to control algolithm and direct current
The research of electric system is relatively more, but the research with regard to converter valve equipment is but few.
Extra-high voltage converter valve mesohigh Insulation Problems are the most prominent, current insulating structure designs or shielding design is big
Part is all to be estimated according to original standard or go to select rational shielding design or insulation by substantial amounts of test
Structure.Or so may result in design result can not meet requirement of engineering, or redundancy is excessive, substantial amounts of test simultaneously
Cost can be increased.And the partial discharge phenomenon such as corona can not be predicted before the test and judge.Intrinsically, insulate
Intensity is exactly the size that insulation system undertakes electric-field intensity, and the essential reason of insulation fault is all because being held in its insulation system
Load electric-field intensity has exceeded its disruptive field intensity and has led to；The situation of electric field or magnetic field improvement is also shielding harness performance simultaneously
Criterion, the analysis of electric field of therefore high voltage direct current transmission converter valve has very important significance.And at present with regard to the change of current
In the research of valve electric field, not improving in the analysis model carrying out setting up during converter valve analysis of electric field of having is changed it is impossible to reflect
The complete Problems of The Electric Field of stream valve；Have is analyzed using former mechanical model when carrying out electric Field Calculation, has so both wasted calculating
Machine resource, makes result of calculation be difficult to convergence again.
Content of the invention
It is an object of the invention to provide a kind of simply examined based on the extra-high voltage direct-current transmission converter valve fault of analysis of electric field
Disconnected method, to realize quick, the Accurate Diagnosis to converter valve insulation fault
For achieving the above object, the extra-high voltage direct-current transmission converter valve method for diagnosing faults based on analysis of electric field of the present invention
Including step as follows:
(1) realistic model according to converter valve extracts structural parameters；
(2) set up converter valve electric Field Calculation model according to the structural parameters that step (1) is extracted；
(3) selection will be added in the type of electric field on converter valve battery computation model, and arranges corresponding excitation and perimeter strip
Part；
(4) analysis of electric field is carried out to converter valve electric Field Calculation model, determine whether that insulation fault occurs and positioning failure
There is position.
(5) according to the analysis of electric field in step (4), the design of shielding construction and the design of valve tower internal components are carried out, or
Person carries out design and the optimization of insulation system.
In described step (1) converter valve structural parameters include the size of metal parts in converter valve, shape, in valve tower
The material properties of all parts in water pipe, solid dielectric insulation, the air gap and converter valve in location parameter and valve tower.
In step (2), the structural parameters extracting are carried out simplifying equivalent, then set up converter valve battery computation model.
The structural parameters extracting are carried out simplifying and equivalent refers to there is topological structure in converter valve with circular hole or inside
Metallic conductor internal structure be equivalent to solid, to be simplified.
Verified after setting up converter valve electric Field Calculation model in step (2).
In described step (3), the type of electric field includes static electric field analysis and transient electric field analysis.
Static electric field analyzes excitation and boundary condition using converter valve stable state or longtime running；Transient electric field analysis is adopted
With the transient state excitation under the conditions of converter valve extreme operating condition or under the conditions of insulation type test and boundary condition.
Carry out analysis of electric field to converter valve electric Field Calculation model in described step (5) to refer to, the air gap electric-field intensity is big
Little and Electric Field Distribution uniformity coefficient；The electric field level on electric-field intensity and surface and direction in solid insulating material；Maximum field
Intensity and position.
The present invention is gone out from the property of electric field based on the extra-high voltage direct-current transmission converter valve method for diagnosing faults of analysis of electric field
Send out, can accurately set up the electric Field Calculation model that can react converter valve insulation characterisitic, can guarantee that the conjunction of computer resource simultaneously again
Reason utilizes；And analyze insulation characterisitic in insulation system according to the actual conditions under different operating modes and judge to be susceptible to office
The position of portion's electric discharge, is accurately positioned fault and position occurs.
Brief description
Fig. 1 is the simplification equivalent process schematic diagram of metal parts electric field model；
Fig. 2 is that metal parts electric field model sets up the schematic shapes that process should be noted；
Fig. 3 is the extra-high voltage converter valve module electric Field Calculation illustraton of model set up；
Fig. 4 is the extra-high voltage converter valve shielding harness electric Field Calculation illustraton of model set up；
Fig. 5 is electric field relationship figure in solid dielectric insulation and air interface；
Fig. 6 is the flow chart of extra-high voltage converter valve analysis of electric field method；
Fig. 7 is the limited element calculation model figure of embodiment；
Fig. 8 is that valve tower solves domain schematic diagram；
Fig. 9 is the electric Field Calculation distribution map calculating；
Figure 10 is the position view that in Fig. 9, electric field is concentrated.
Specific embodiment
As shown in fig. 6, being comprised the following steps based on the extra-high voltage direct-current transmission converter valve method for diagnosing faults of analysis of electric field:
A, in the converter valve model of Preliminary design extract structural parameters: include converter valve in all metal parts chi
The parameters such as very little, shape, position in valve tower；The parameter such as water pipe, solid dielectric insulation, the air gap in valve tower；In converter valve
The material properties of all parts, it is important that dielectric constant and electrical conductivity in analysis of electric field.
B, the valve tower structure parameter to extraction are simplified and equivalent analysis, set up the converter valve mould being suitable for electric Field Calculation
Type.
C, judge set up electric Field Calculation model whether correct: be analyzed by the contrast with realistic model, judge to build
Can vertical computation model correctly reflect the Electric Field Characteristics of converter valve.If there is error or difference, then return b step
Suddenly, re-start analyzing and setting up of model.
D, selection type of electric field to be analyzed: include static electric field analysis and transient electric field calculates；
E, determine excitation and the boundary condition of electric Field Calculation according to the type selecting electric field to be analyzed: static electric field master
To be analyzed is Electric Field Distribution, the operation of converter valve therefore to be combined and the valve Room for a long time or in the case of stable operation for the converter valve
In actual conditions come to determine excitation and boundary condition；Transient electric field Main Analysis converter valve be in extreme in the case of valve tower
Can insulation system normally run, and the transient state extreme voltage therefore first having to accurately obtain converter valve under calculating experimental condition divides
, as excitation, actual test or running environment are as border for cloth.
F, analysis of electric field, are analyzed to the electric field of converter valve after the completion of calculating: the air gap electric-field intensity size and electricity
Field distribution uniformity coefficient；The electric field level on electric-field intensity and surface and direction in solid insulating material；Maximum field intensity and
Position；The size and Orientation of the electric field by undertaking in insulation system or insulating materials can theoretically judge that its insulation is special
Property or whether occur electric discharge situations such as；Can also be analyzed according to the size variation of electric field or judge converter valve shielding construction
Performance.
G, according to electric Field Calculation result instruct or optimization design: by the analysis of electrostatic field, converter valve can be obtained long
Electric Field Distribution in phase or steady-state operation, carries out the design of shielding construction and setting of valve tower internal components according to this result
Meter, provides foundation for analysis converter valve longtime running characteristic simultaneously；Analyzed by transient electric field, can analyze and judge converter valve
Insulation system whether meet requirement, and according to result carrying out design and the optimization of insulation system.
It is that extra-high voltage direct-current transmission converter valve metal parts electric Field Calculation model is equivalent and simplified model mode as shown in Figure 1
Schematic diagram.
Metal parts is electrical body in valve tower, in electric Field Calculation metal parts from as first-class current potential body, in conductor
Internal electric field is zero everywhere, and the therefore shape of conductor does not affect substantially on conductor external electric field, therefore can be according to Fig. 1 institute
Show actual metal pattern is carried out simplify equivalent.Circular hole is carried for some in converter valve or there is topological structure inside
The metallic conductor such as internal structure such as radiator, tce, metal tube mother, radome can go letter according to the mode shown in Fig. 1
Change, internal structure will be set to solid construction.
It is the principle during extra-high voltage direct-current transmission converter valve metal parts electric Field Calculation model is set up as shown in Figure 2.
Electric-field intensity in the metal outer insulation system that in electric Field Calculation, emphasis considers, the therefore outside shape of metal parts
Shape and size but decide electric-field intensity and the distribution of electric field.Therefore in the foundation and equivalent process of model, metal parts
Outer shape and size are definitely immutable it is necessary to and being consistent in practice.Especially the wedge angle of metal parts or
The positions such as fillet, rounded corner, position as shown in Figure 2 can not be changed.For converter valve band point metal parts such as
The size and dimension in the outside such as electric current row, metallic water pipe, metal beam, radome has and will carry out according to the mode shown in Fig. 2
The foundation of model.
It is the finite element mould of the extra-high voltage direct-current transmission converter valve components of equivalent and simplification set up as shown in Figure 3
Type.
After being extracted the parameter of actual component model, carry out simplifying and equivalent, the metal beam of assembly, IGCT two ends
Radiator, the metal parts such as tce shell must keep original size and dimension；IGCT is also carried out according to original shape
Setting, but be intended to root and open or turn off two states to the different material properties of IGCT setting.
It is the model of the extra-high voltage direct-current transmission converter valve shielding harness of equivalent and simplification set up as shown in Figure 4.
In the electric Field Calculation model of converter valve, shielding harness is also that comparison is crucial, radome is carried out simplify equivalent, guarantor
Hold size and the outer shape of radome, internal hollow-core construction has been equivalent to solid construction；The electric current row of valve tower both sides protects
Stay the shape and size outside it, the shape of conductor is carried out simplification equivalent；The grading ring of end of incoming cables has been also carried out
Effect simplifies.
It is the electric field relationship figure on solid dielectric insulation surface as shown in Figure 5.According to joining relation on interface for the electric field
Can obtain:
In formula, e1tAnd e2tRepresent that in the air is parallel with interface with electric field tangential component in solid insulating material respectively
Component；e1nAnd e2nRepresent that in the air is the component vertical with interface with electric field normal component in solid insulating material respectively；
ε1And ε2It is respectively the dielectric constant in air and solid insulating material, ε2γFor the relative dielectric constant in solid insulating material.
If e in electric fieldnRatio is larger, is strong vertical component on medium respectively face, then be very big in the gap of both sides electric field；
If e in electric fieldtRatio is larger, is weak vertical component on medium respectively face, then be smaller in the gap of both sides electric field；
In the case of two kinds, the sliding lightning pressure of dielectric surface is different, therefore calculates and analysis dielectric surface electric field component is for design
Insulation system is critically important.
It is the complete converter valve electric Field Calculation model set up as shown in Figure 7.
Shown is the FEM model setting up converter valve assembly and shielding construction system in figs. 3 and 4.At this
On the basis of two steps, according to actual size, by complete valve towers of composition such as assembly, shielding harness, saturable reactor, electric current rows
FEM model.The solution of valve tower is configured with according to actual valve Room size, and such as valve Room structure is 80m*40m*30m,
The solution domain sizes set up as shown in Figure 8 are just 80m*40m*30m, wherein the distance between valve top of tower and solution domain bottom
It is exactly the height apart from ground for the valve tower.Six faces for the solution domain shown in Fig. 8 are all entered according to First Boundary Condition
Row setting, is processed according to ground connection, all zero potential surfaces in six faces.
The converter valve FEM model set up according to this method, includes radome, grading ring, water main, metal tube is female,
Assembly etc. to the part determining Electric Field Distribution it is ensured that the complete and reliability of electric Field Calculation model, can be complete and accurately anti-
Mirror the Electric Field Characteristics of converter valve, the FEM model of converter valve includes all of metal parts, all of air is exhausted
Edge structure and solid insulation structure can accurately retain its actual size.Colleague through simplification and equivalent it is established that come
Converter valve finite element electric field computation model has the operability possessing computing in practice.
It is by an example of analysis of electric field as shown in Figure 8,9.
According to several steps before in this method, it is necessary to carry out the labor of electric field after completing overall calculation.Fig. 7
The air gap distance of middle valve tower interlayer is 800mm, and voltage difference 200kv of interlayer.Through calculating, maximum field is on assembly top
The metal apex in portion, maximum field is 1.3kv/mm.Electric Field Distribution in interlayer air can be analyzed by Fig. 7 more equal
Even.
In order to examine whether the phenomenons such as shelf depreciation, at maximum field position near point as study right
As.The electric field intensity of Fig. 8 point is respectively as follows: 1.30kv/mm, 1.29kv/mm, 1.31kv/mm, 1.26kv/mm, 1.31kv/
mm.Therefore may determine that the situation that electric field is not mutated near metal apex, there is not the situation of severe non-uniform electric field.Cause
This may determine that the dielectric strength in the valve tower interlayer air gap of this structure meets requirement, and is not in insulation fault.
According to analysis of electric field method of the present invention, can accurately and completely assess the characteristic of insulation system and electricity in converter valve design
Magnetic screen efficiency, the design for converter valve and offer method is provided.
The concrete advantage of extra-high voltage direct-current transmission converter valve method for diagnosing faults based on analysis of electric field is as follows:
1. converter valve electric Field Calculation model sets up that process is succinctly accurate, using electric field characteristic to converter valve components and other
Structure carries out equivalent-simplification, retains the model parameter more crucial on electric field impact simultaneously；
2. include radome, grading ring, water main in converter valve electric Field Calculation model, metal tube mother, assembly etc. are fought to the finish
Determine the part of Electric Field Distribution it is ensured that the complete and reliability of electric Field Calculation model；
3., during converter valve electric Field Calculation model is set up, the parameter of all of insulation system and part is all to control
, converter valve insulation system to the later stage and the improvement of shielding construction and optimization design very convenient and use；
4. can be to electricity on various operating mode lower valve tower maximum field intensity locations, Electric Field Distribution uniformity coefficient, concern position
Field vector etc. carries out detailed calculating, the insulation characterisitic analyzing converter valve and the position judging to be susceptible to shelf depreciation.
Claims (8)
1. the extra-high voltage direct-current transmission converter valve method for diagnosing faults based on analysis of electric field is it is characterised in that what the method included
Step is as follows:
(1) realistic model according to converter valve extracts structural parameters；
(2) set up converter valve electric Field Calculation model according to the structural parameters that step (1) is extracted；
(3) selection will be added in the type of electric field on converter valve electric Field Calculation model, and arranges corresponding excitation and boundary condition；
(4) analysis of electric field is carried out to converter valve electric Field Calculation model, determine whether that insulation fault occurs and positioning failure occurs
Position；
(5) according to the analysis of electric field in step (4), carry out the design of shielding construction and the design of valve tower internal components, or enter
The design of row insulation system and optimization；
The part of the decision Electric Field Distribution that converter valve electric Field Calculation model includes has: radome, grading ring, water main, metal
Pipe mother and assembly.
2. the extra-high voltage direct-current transmission converter valve method for diagnosing faults based on analysis of electric field according to claim 1, it is special
Levy and be: in described step (1) converter valve structural parameters include the size of metal parts in converter valve, shape, in valve tower
The material properties of all parts in water pipe, solid dielectric insulation, the air gap and converter valve in location parameter and valve tower.
3. the extra-high voltage direct-current transmission converter valve method for diagnosing faults based on analysis of electric field according to claim 1, it is special
Levy and be: in step (2), the structural parameters extracting are carried out simplifying equivalent, then set up converter valve electric Field Calculation model.
4. the extra-high voltage direct-current transmission converter valve method for diagnosing faults based on analysis of electric field according to claim 3, it is special
Levy and be: the structural parameters extracting are carried out simplifying with equivalent referring to there is topological structure in converter valve with circular hole or inside
Metallic conductor internal structure be equivalent to solid, to be simplified.
5. the extra-high voltage direct-current transmission converter valve method for diagnosing faults based on analysis of electric field according to claim 1, it is special
Levy and be: verified after setting up converter valve electric Field Calculation model in step (2).
6. the extra-high voltage direct-current transmission converter valve method for diagnosing faults based on analysis of electric field according to claim 1, it is special
Levy and be: in described step (3), the type of electric field includes static electric field analysis and transient electric field analysis.
7. the extra-high voltage direct-current transmission converter valve method for diagnosing faults based on analysis of electric field according to claim 6, it is special
Levy and be: static electric field analyzes excitation and boundary condition using converter valve stable state or longtime running；Transient electric field analysis is adopted
With the transient state excitation under the conditions of converter valve extreme operating condition or under the conditions of insulation type test and boundary condition.
8. the extra-high voltage direct-current transmission converter valve fault diagnosis based on analysis of electric field according to any one of claim 1-7
Method refers to it is characterised in that carrying out analysis of electric field to converter valve electric Field Calculation model in described step (4), the air gap electricity
Field intensity size and Electric Field Distribution uniformity coefficient；The electric field level on electric-field intensity and surface and direction in solid insulating material；
Maximum field intensity and position.
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| CN104462655A (en) * | 2014-11-12 | 2015-03-25 | 国家电网公司 | Method for analog calculation of safety performance of GIS metal pipeline system |
| CN106547953A (en) * | 2016-10-17 | 2017-03-29 | 国网辽宁省电力有限公司电力科学研究院 | A kind of method of acquisition 800kV dc bus metal oxide arrester Potential distributions |
| CN108021748A (en) * | 2017-12-01 | 2018-05-11 | 国网冀北电力有限公司电力科学研究院 | Electric Field Simulation method and system for high-voltage large-capacity flexible direct current converter valve |
| CN109921410A (en) * | 2017-12-12 | 2019-06-21 | 中电普瑞科技有限公司 | The method for arranging and device of a kind of series compensation device and peripheral equipment |
| CN108334671A (en) * | 2018-01-12 | 2018-07-27 | 许继电气股份有限公司 | A kind of converter valve submodule busbar electric power check method and device |
| CN108647396B (en) * | 2018-04-13 | 2020-11-13 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | Key equipment fault risk assessment method for improving reliability of converter valve |
| CN108667006B (en) * | 2018-04-13 | 2021-02-19 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | Single-valve digital broadband fault risk analysis method for improving reliability of converter valve |
| CN109270418A (en) * | 2018-06-11 | 2019-01-25 | 哈尔滨理工大学 | The tangential and adjustable paper oil insulation edge flashing electrode system of normal electric field |
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| CN102486515B (en) * | 2010-12-01 | 2015-04-29 | 中国电力科学研究院 | Fault current composite test method for high-voltage direct current power transmission converter valve |
| CN202068184U (en) * | 2010-12-09 | 2011-12-07 | 国家电网公司 | Cascade converter station and cascade multi-terminal HVDC system |
| CN103063903B (en) * | 2012-12-10 | 2014-02-19 | 国网智能电网研究院 | Overvoltage computing method of modular multi-level converter |
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