阅读说明：本技术 一种考虑可溶污秽成分的绝缘子耐受电压梯度计算方法 (A kind of insulator withstanding voltage gradient calculation method considering solvable filthy ingredient ) 是由 杨成顺 张东东 刘欣 黄宵宁 倪良华 郝思鹏 张志劲 于 2019-07-23 设计创作，主要内容包括：本发明公开了一种考虑可溶污秽成分的绝缘子耐受电压梯度计算方法,该方法包括步骤1、计算绝缘子表面各可溶污秽成分的等值盐密含量分数；步骤2、基于硫酸钙溶解特性,对绝缘子表面各可溶污秽成分的等值盐密和灰密进行修正；步骤3、基于绝缘子表面各可溶污秽成分的等值盐密修正值,修正各可溶污秽成分对应的等值盐密含量分数；步骤4、计算各可溶污秽成分对应的闪络电压梯度,将计算后的结果进行叠加,得到混合污秽成分下的绝缘子耐受电压梯度；本发明解决了目前不能准确的计算出外绝缘的电压耐受度的问题。(The invention discloses a kind of insulator withstanding voltage gradient calculation method for considering solvable filthy ingredient, the method comprising the steps of 1, calculates the equivalent salt density content score of each solvable filthy ingredient of insulator surface；Step 2 is based on calcium sulfate dissolution characteristics, the equivalent salt density of solvable filthy ingredient each to insulator surface and ash is close is modified；Step 3, the equivalent salt density correction value based on each solvable filthy ingredient of insulator surface correct the corresponding equivalent salt density content score of each solvable filth ingredient；Step 4 calculates the corresponding flashover voltage gradient of each solvable filth ingredient, and the result after calculating is overlapped, obtains mixing the insulator withstanding voltage gradient under filthy ingredient；The present invention solves the problems, such as that the voltage endurance of external insulation can not accurately be calculated at present.)

1. a kind of insulator withstanding voltage gradient calculation method for considering solvable filthy ingredient, which is characterized in that including walking as follows It is rapid:

Calculate the equivalent salt density content score of each solvable filthy ingredient of insulator surface, wherein insulator surface is each described solvable Filthy ingredient includes CaSO₄, NaCl and following solvable filthy ingredient at least one, the solvable filthy ingredient further includes NaCl、KNO₃、NH₄NO₃、NaNO₃、Ca(NO₃)₂And MgSO₄；

Based on calcium sulfate dissolution characteristics, the equivalent salt density of the solvable filthy ingredient each to insulator surface and ash is close repairs Just；

Based on the equivalent salt density correction value of each solvable filthy ingredient of insulator surface, each solvable filthy ingredient pair is corrected The equivalent salt density content score answered；

The corresponding flashover voltage gradient of each solvable filthy ingredient is calculated, the result after calculating is overlapped, is mixed Insulator withstanding voltage gradient under filthy ingredient.

2. insulator withstanding voltage gradient calculation method according to claim 1, which is characterized in that each solvable filth The equivalent salt density content score η of ingredient_iCalculating formula are as follows:

I indicates certain solvable filthy ingredient, α_iFor the corresponding equivalent salt density contribution rate of the solvable filthy ingredient, dimensionless；β_iFor this The mass fraction of solvable filth ingredient, dimensionless.

3. insulator withstanding voltage gradient calculation method according to claim 2, which is characterized in that it is described it is solvable it is filthy at It is divided into NaCl, NH₄NO₃、KNO₃、NaNO₃、Ca(NO₃)₂、MgSO₄And CaSO₄When the corresponding equivalent salt density contribution rate be respectively 1.00,0.855,0.733,0.784,0.550,0.462 and 0.485.

4. insulator withstanding voltage gradient calculation method according to claim 1, which is characterized in that the insulator surface The amendment type of equivalent salt density are as follows:

ESDD is insulator surface equivalent salt density measured value, ESDD in formula^*For consider calcium sulfate microsolubility after insulator surface etc. It is worth the close correction value of salt, η_{Calcium sulfate}For the equivalent salt density content score of calcium sulfate；It is corresponding etc. for sulfuric acid calcium component after amendment It is close to be worth salt.

5. insulator withstanding voltage gradient calculation method according to claim 4, which is characterized in that describedTable Up to formula are as follows:

In formula, α_{Calcium sulfate}For calcium sulfate equivalent salt density contribution rate, 0.485 is taken；A is calcium sulfate saturated concentration critical value at 20 DEG C, is taken 3.277g/L；V is that insulator surface is saturated attached water amount, takes 20-30ml；A_sFor insulator surface product.

6. insulator withstanding voltage gradient calculation method according to claim 5, which is characterized in that the insulator surface The close amendment type of ash are as follows:

In formula, the close measured value of NSDD insulator surface ash, NSDD^*For its correction value, α_{Calcium sulfate}For calcium sulfate equivalent salt density contribution rate, η_{Calcium sulfate}For the equivalent salt density content score of calcium sulfate.

7. insulator withstanding voltage gradient calculation method according to claim 6, which is characterized in that it is described it is solvable it is filthy at Divide the amendment type of corresponding equivalent salt density content score are as follows:

In formula, η_iFor the equivalent salt density content score of solvable filthy ingredient.

8. insulator withstanding voltage gradient calculation method according to claim 7, which is characterized in that the mixing it is filthy at The calculating formula of insulator withstanding voltage gradient under point are as follows:

A in formula_iFor the corresponding pollution flashover gradient factor of soluble ingredient i；n_iRefer to for the corresponding filthy feature that influences of solvable filth ingredient i Number, m are the close influence characteristic index of ash；Wherein m is determined by insulator pattern, n_i、A_iIt is true by insulator pattern and filthy ingredient type It is fixed.

Technical field

The present invention relates to power transmission and distribution filth insulation technical fields, and in particular to a kind of insulation for considering solvable filthy ingredient Sub- withstanding voltage gradient calculation method.

Background technique

Transmission line of electricity and the outdoor electrical equipment (especially operating in industrial area, coastal and varieties in saline-alkali areas) of substation warp The often pollution such as saline and alkaline, dust, birds droppings by industrial filthy or nature.In dry conditions, the resistance of these filthy dust is very Greatly, it is safe from danger to the reliability service of insulator；But when air humidity height, such as in unfavorable gas such as mist, dew, drizzle, molten snow As under the conditions of, the filthy dust of insulator surface will be wet, its surface conductance and leakage current will under applied voltage effect It greatly increases, is reduced so as to cause contaminated insulator surface electric property and comprehensive flashover even occurs, to seriously threaten electric power The safe and stable operation of system.

Because of the difference of pollution sources, the filthy chemical component that all kinds of particulate matters are deposited in insulator surface in atmosphere is also because of atmosphere The difference of environment and pollution sources and there are great differences.China mostly uses equivalent salt deposit density and equivalent ash close greatly to evaluate at present The degree of fouling on electroceramics surface.But it is very big to find that the insulator contamination voltage under the conditions of identical salt is close has in practical applications Difference, if monovalent salt (mainly using NaCl as representative) ingredient contained by filthy substance is more, pollution flashover voltage is with regard to relatively low；Contained two Valence salt is (mainly with CaSO₄To represent) it is more, then pollution flashover voltage is with regard to higher；Different ashes also have different adsorptivity and water suction Property, it will have a direct impact on the accumulation and water imbibition of pollution severity of insulators, this can also change the condition of pollution flashover generation.

According to it is domestic it is existing generally acknowledge as a result, soluble ingredient common during insulator surface is naturally filthy mainly have NaCl, NaNO₃、KNO₃、MgSO₄、NH₄NO₃、Ca(NO₃)₂、CaSO₄.Filthy chemical component has directly influenced the generation of pollution flashover accident, The insulator withstanding voltage gradient under different terrain geomorphologic conditions is caused to have larger difference.But it insulate both at home and abroad in assessment at present When the withstanding voltage gradient of substring, a kind of this influence of ingredient of sodium chloride is only only accounted for, and do not have a kind of method can be at present The factors such as various filthy ingredient conductivity, solubility are comprehensively considered, so that the mixing that more realistic situation is calculated is filthy Insulator chain withstanding voltage gradient under ingredient causes existing pollution degree assessment and the calculating of tolerance gradient to still have scarce It falls into, the selection of external insulating level and the formulation of antifouling work strategy lack scientific foundation.

Summary of the invention

The purpose of the present invention is to provide a kind of insulator withstanding voltage gradient calculation method for considering solvable filthy ingredient, To solve to comprehensively consider in the prior art various filthy ingredients, external insulation voltage endurance is caused to calculate asking for inaccuracy Topic.

In order to achieve the above objectives, the present invention adopts the following technical solutions realization:

A kind of insulator withstanding voltage gradient calculation method considering solvable filthy ingredient, includes the following steps:

Step 1, the equivalent salt density content score for calculating each solvable filthy ingredient of insulator surface, wherein insulator surface Each solvable filthy ingredient includes CaSO₄, NaCl and following solvable filthy ingredient at least one, it is described it is solvable it is filthy at Dividing further includes NaCl, KNO₃、NH₄NO₃、NaNO₃、Ca(NO₃)₂And MgSO₄；Step 2 is based on calcium sulfate dissolution characteristics, to insulation The equivalent salt density of each solvable filthy ingredient in sublist face and ash is close is modified.

Step 3, the equivalent salt density correction value based on each solvable filthy ingredient of insulator surface, are corrected each described solvable The corresponding equivalent salt density content score of filthy ingredient.

Step 4 calculates the corresponding flashover voltage gradient of each solvable filthy ingredient, and the result after calculating is folded Add, obtains mixing the insulator withstanding voltage gradient under filthy ingredient.

The present invention has the advantages that

1, the insulator tolerance gradient and measured result that the method for the present invention is calculated are coincide substantially, and relative error is 8% Within, show that the method for the present invention can be used directly to calculate and mix insulator tolerance gradient under filthy ingredient, solves at present not The problem of voltage endurance of external insulation can accurately be calculated.

2, really reflect the insulator electricity of different dirty source areas by mixing the calculating of insulator tolerance level under filthy ingredient Gas characteristic can accurately instruct the selection design and the development of anti-pollution measure of external insulating level.

Detailed description of the invention

Fig. 1 is the flow chart of the specific embodiment of the invention；

Fig. 2 is the flashover voltage gradient calculated result comparison diagram that conventional method is used in the specific embodiment of the invention；

Fig. 3 is the flashover voltage gradient calculated result comparison diagram that the specific embodiment of the invention uses the method for the present invention.

Specific embodiment

To be easy to understand the technical means, the creative features, the aims and the efficiencies achieved by the present invention, below with reference to Specific embodiment, the present invention is further explained.

Using glass mould insulator as object, according to its filth near Highway, commercial plant area and coastal area Test result carries out artificial pollution test, obtains its withstanding voltage gradient, is then calculated respectively with traditional withstanding voltage gradient Method and the method for the present invention calculate the tolerance gradient of insulator, compare with test result, are illustrated in the present invention with this Hold.Insulator structure parameter is as shown in table 1.

1 insulator structure parameter of table

A kind of insulator withstanding voltage gradient calculation method detailed process considering solvable filthy ingredient proposed by the present invention Figure such as Fig. 1, key step are as follows:

Step 1, according to solvable filthy component type and mass fraction, calculate each solvable filthy ingredient of insulator surface etc. It is worth the close content score of salt, wherein each solvable filthy ingredient of insulator surface includes readily soluble filthy ingredient CaSO₄, slightly soluble it is dirty At least one of dirty ingredient NaCl and following readily soluble filthy ingredient, the readily soluble filthy ingredient further includes NaCl, KNO₃、 NH₄NO₃、NaNO₃、Ca(NO₃)₂And MgSO₄；Step 2 is based on calcium sulfate dissolution characteristics, the solvable dirt each to insulator surface The equivalent salt density of dirty ingredient and ash is close is modified；

Step 3, the equivalent salt density correction value based on each solvable filthy ingredient of insulator surface, are corrected each described solvable The corresponding equivalent salt density content score of filthy ingredient；

Step 4 calculates the corresponding flashover voltage gradient of each solvable filthy ingredient, and the result after calculating is folded Add, obtains mixing the insulator withstanding voltage gradient under filthy ingredient.

The step of equivalent salt density content score of each solvable filthy ingredient is calculated in step 1 are as follows: according to it is each it is solvable it is filthy at Point equivalent salt density contribution rate, the close content score of mass fraction certainty equivalents salt, i.e.,

I indicates certain solvable filthy ingredient, α in formula_iIt is immeasurable for the corresponding equivalent salt density contribution rate of the solvable filthy ingredient Guiding principle；β_iFor the mass fraction of the solvable filthy ingredient, dimensionless.α under typical soluble filth ingredient_iValue are as follows:

In step 2, insulator surface equivalent salt density measured value is modified, in specific implementation the step of are as follows: first count The practical salt density value for calculating other outer easily soluble components of the calcium sulfate that is removed, is determining calcium sulfate according to the geomery of insulator Practical equivalent salt density value, then the two is added, i.e.,

ESDD is insulator surface equivalent salt density measured value, unit mg/cm in formula²；ESDD^*To consider that calcium sulfate is micro- Equivalent salt density correction value after dissolubility, η_{Calcium sulfate}For the equivalent salt density content score of calcium sulfate；For amendment after calcium sulfate at Divide corresponding equivalent salt density, calculation expression are as follows:

In formula, SDD^* _{Calcium sulfate}For CaSO after amendment₄Corresponding salt density value, mg/cm²；α_{Calcium sulfate}For CaSO₄Equivalent salt density contribution Rate takes 0.485；A is calcium sulfate saturated concentration critical value at 20 DEG C, takes 3.277g/L；V is that insulator surface is saturated attached water amount, Generally take 20-30ml；A_sFor insulator surface product, cm²。

In step 2, the close measured value of insulator surface ash is modified, in specific implementation the step of are as follows: first will be equivalent The close measured value of salt subtracts equivalent salt density correction value, then divided by the equivalent salt density contribution rate of calcium sulfate, obtains undissolved calcium sulfate Then corresponding mass density is added with the close measured value of ash, obtains the revised close value of ash, i.e.,

NSDD is the close measured value of insulator surface ash, unit mg/cm in formula²；NSDD^*For its correction value.

In step 3, the corresponding equivalent salt density content score of each solvable filthy ingredient is modified, in specific implementation Step are as follows: utilize equivalent salt density correction value, the practical equivalent salt density value of calcium sulfate, correct the equivalent salt density content of easily soluble component respectively The equivalent salt density content score of score and calcium sulfate, i.e.,

In step 4, calculate the insulator withstanding voltage gradient mixed under filthy ingredient, in specific implementation the step of are as follows: The corresponding flashover voltage gradient of every kind of filth ingredient is calculated, then multiplied by revised equivalent salt density content score, then is folded Add, i.e.,

A in formula_iFor the corresponding pollution flashover gradient factor of soluble ingredient i；n_iRefer to for the corresponding filthy feature that influences of soluble ingredient i Number, m are the close influence characteristic index of ash.Wherein m is determined by insulator pattern, n_i、A_iIt is determined by insulator pattern and filthy ingredient type It is fixed.

Select the LXY4-160 glass insulator tolerance in highway, chemical plant, coastal area operation terraced in the present embodiment Degree, which is calculated, illustrates the content of present invention as embodiment.This area's pollution severity of insulators composition quality score and the close ash of salt are close, resistance to It is as shown in the table by voltage gradient test value.

Table 2, insulator arc-over test result under the filthy ingredients of several mixing

It there is no a kind of method at present, it may be considered that solvable filth ingredient is counted to be resistant to gradient to overhead transmission line insulator It calculates.Traditional method is directly to be calculated by equivalent salt density and the close value of ash, it may be assumed that

E_L=A × ESDD^-n×NSDD^-m

In engineering, for LXY₄- 160 insulators, A take 15.5, n that 0.34, m is taken to take 0.13, obtained calculated result and its It is as shown in Figure 2 with the relative error of measured value.From data result it can be seen that the pollution flashover voltage gradient obtained under conventional method with Pollution flashover voltage gradient relative error under actual conditions is larger, up to 35%.

The insulator withstanding voltage gradient mixed under solvable filthy ingredient is calculated using this paper inventive method.First, in accordance with Step 1- step 3 calculates the equivalent salt density content score of each solvable filthy ingredient according to filthy component type and mass fraction； It is based on calcium sulfate dissolution characteristics again, insulator surface equivalent salt density, ash close are modified；It is then based on equivalent salt density amendment Value corrects the corresponding equivalent salt density content score of each solvable filth ingredient:

Finally calculate the insulator withstanding voltage gradient mixed under filthy ingredient, calculating formula are as follows:

To LXY in this present embodiment₄- 160 insulators, m, n_i、A_iValue are as follows:

The insulator tolerance gradient calculated value being calculated mix under filthy ingredient is brought into as shown in figure 3, can be seen by Fig. 3 Out, the insulator tolerance gradient and measured result that the method for the present invention is calculated are coincide substantially, and relative error is within 8%, table Bright the method for the present invention, which can be used directly to calculate, mixes insulator tolerance gradient under filthy ingredient, to really reflect different dirty sources The insulator electrical characteristic in area, and accurately instruct the selection design and the development of anti-pollution measure of external insulating level.

As known by the technical knowledge, the present invention can pass through the embodiment party of other essence without departing from its spirit or essential feature Case is realized.Therefore, embodiment disclosed above, in all respects are merely illustrative, not the only.Institute Have within the scope of the present invention or is included in the invention in the change being equal in the scope of the present invention.