CN105184067A - Isolator pollution flashover state fuzzy evaluation method - Google Patents

Abstract

The present invention relates to an isolator pollution flashover state fuzzy evaluation method. The method comprises the following steps of: establishing an isolator pollution flashover state fuzzy comprehensive evaluation index system, selecting two evaluation items, i.e. an inherent factor and an environmental factor, and then establishing an index system of the evaluation items; partitioning an evaluation level, determining a set consisting of evaluation results, aiming at the index system of the evaluation items, obtaining an evaluation matrix of to-be-evaluated objects by the set of the evaluation results, and performing normalization processing on indexes which are more excellent when being greater and indexes which are more excellent when being smaller; and giving weights of the evaluation indexes by using an entropy weight method and an analytic hierarchy process, combining evaluation level partitioning of the index system, giving a membership function between boundary intervals, and then performing evaluation on a pollution flashover state of an isolator by using a j-th evaluation index of an i-th item layer, wherein a membership set of the evaluation levels is an evaluation result of the evaluation indexes. By adopting the fuzzy comprehensive evaluation method, influence weights of different influence factors are given and the pollution flashover state of the isolator is finally determined.

Description

Insulator contamination Fuzzy Assessment Method

Technical field

The invention belongs to power protection technology field, relate to a kind of high-tension line element insulating, be specifically related to a kind of insulator contamination Fuzzy Assessment Method.

Background technology

Power industry is the basis of the national economic development, and along with the fast development of economic society, great changes will take place for physical environment situation, and all kinds pollutant is on the increase, and the inclement weather such as haze, sandstorm is also more and more serious.Power circuit and equipment pollution flashover accident happen occasionally, and the harm caused electric system is increasing.Drawn by historical data, line insulation pollution flashover accident number is only second to thunderbolt, but the loss of outage caused due to pollution flashover is but more than 10 times of lightning strike accident, and insulator contamination research is the important indicator of electric power netting safe running.

Summary of the invention

In order to overcome the deficiencies in the prior art, the invention provides a kind of insulator contamination Fuzzy Assessment Method, adopt fuzzy synthetic appraisement method, the weighing factor of given different factor of influence, finally determines the pollution flashover state of insulator.

Technical scheme of the present invention is: a kind of insulator contamination Fuzzy Assessment Method, comprise the steps: step one: set up insulator contamination state comprehensive fuzzy evaluation index system, two are selected to pass judgment on project, i.e. intrinsic factor and environmental factor, then sets up the index system of a judge project; Step 2: divide opinion rating, determine the set that evaluation result forms, for the index system of the project of judge, is obtained the Evaluations matrix of object to be evaluated by evaluation result set, and carries out standardization to more large more excellent type index and more little more excellent type index; Step 3: the weight utilizing entropy assessment and the given evaluation index of analytical hierarchy process${\mathrm{\&omega;}}_g=\frac{1-H_g}{N-{\mathrm{\&Sigma;}}_{g=1}^N{H}_g},$Wherein, 0 < < ω_g< < 1 and${\mathrm{\&Sigma;}}_{g=1}^N{\mathrm{\&omega;}}_g=1,H_g=-{\mathrm{K\&Sigma;}}_{K=1}^M{f}_{kg}{\mathrm{lnf}}_{kg},$K=1/lnM,wherein, H_g∈ [0,1], and regulation, work as f_kgwhen=0, f_kglnf_kg=0; Step 4: the opinion rating in conjunction with index system divides, provide the membership function between each watershed area, then assess by the pollution flashover state of a jth judging quota to insulator of i-th item layer, the degree of membership set of opinion rating is the assessment result to evaluation index.In described step one index system of intrinsic factor comprise insulator retting-flax wastewater, run the breakage of the time limit and insulator, chap, aging, hydrophobic nature situation, the index system of environmental factor comprises pollution severity of insulators situation, meteorological condition, temperature and humidity.In described step 2, opinion rating adopts 5 grades to make energy, the pollution flashover situation of insulator is divided into " outstanding ", " well ", " qualified ", " attention " and " seriously ".The described standardization processing method to more large more excellent type index is:i=1,2 ..., m; J=1,2 ..., n; Carrying out standardization processing method to more little more excellent type index is:i=1,2 ..., m; J=1,2 ..., n.The middle-level analytic approach of described step 3 is analyzed the relation between insulator and each influence factor, to two-level index, with affiliated first class index for criterion compares between two, and Judgement Matricies.In described step 4, membership function adopts triangle and half trapezoidal distribution function.Described evaluation method also comprises step: adopt weighted mean Fuzzy Model for Comprehensive, retains main judging quota to the evaluation of insulator contamination state and single judging quota to the evaluation of insulator contamination state.

The present invention has following good effect: adopt fuzzy synthetic appraisement method, the weighing factor of given different factor of influence, finally determines the pollution flashover state of insulator.

Accompanying drawing explanation

Fig. 1 is specific embodiment of the invention comprehensive evaluation process flow diagram.

Embodiment

Contrast accompanying drawing below, by the description to embodiment, the specific embodiment of the present invention is as the effect of the mutual alignment between the shape of involved each component, structure, each several part and annexation, each several part and principle of work, manufacturing process and operation using method etc., be described in further detail, have more complete, accurate and deep understanding to help those skilled in the art to inventive concept of the present invention, technical scheme.

Fuzzy synthetic appraisement method uses fuzzy mathematics Linear Transformation principle and maximum membership grade principle, considers that multiple uncertain factor affects, and uses fuzzy mathematics instrument to make comprehensive evaluation to things.By membership function qualitative factor quantification, according to each index weights, comprehensive evaluation is carried out to each factor, thus relatively objective evaluation is made to multifactor impact object.

According to the related data that transmission line foundation data and insulator contamination are tested, based on the intrinsic factor of insulator and running environment factor, set up insulator contamination state comprehensive fuzzy evaluation index system, the index system of intrinsic factor comprises insulator retting-flax wastewater, runs the breakage of the time limit and insulator, chaps, aging, hydrophobic nature situation, and the index system of environmental factor comprises pollution severity of insulators situation, meteorological condition, temperature and humidity.According to fuzzy mathematics theory, 5 grades of systems can be made and describing more accurately being evaluated things.Insulator contamination state is divided into " outstanding ", " well ", " qualified ", " attention ", " seriously " these 5 grades herein, evaluation indice is as follows.L={ " outstanding ", " well ", " qualified ", " attention ", " seriously " }, for the index in appraisement system, the Evaluations matrix of object to be evaluated can be obtained by Comment gathers.Because evaluation index is divided into more large more excellent type and more little more excellent type 2 class, there is different standardization processing methods for dissimilar index.To the standardization processing method of more large more excellent type index be:i=1,2 ..., m; J=1,2 ..., n; Carrying out standardization processing method to more little more excellent type index is:i=1,2 ..., m; J=1,2 ..., n.Utilize the weight of entropy assessment and the given evaluation index of analytical hierarchy processwherein, 0 < < ω_g< < 1 andk=1/lnM,wherein, H_g∈ [0,1], and regulation, work as f_kgwhen=0, f_kglnf_kg=0; Membership function characterizes the degree or the grade that belong to fuzzy set L, i.e. fuzzy characteristic function.In insulator contamination state model of fuzzy synthetic evaluation of the present invention, the existing qualitative factor of comment factor also has quantitative factor, according to the data characteristics of set of factors, selects the distribution function form of triangle and half trapezoidal combination.Opinion rating in conjunction with index system divides, provide the membership function between each watershed area, then assess by the pollution flashover state of a jth judging quota to insulator of i-th item layer, the degree of membership set of opinion rating is the assessment result to evaluation index.In order to ensure objectivity and the authenticity of fuzzy overall evaluation result, not only to consider the impact of main judging quota on insulator contamination state, also will retain all information of single judging quota, therefore select weighted mean Fuzzy Model for Comprehensive herein.

Any one evaluation all can be subject to the impact of subjective factor, can not the objectivity of embodiment of evaluation completely.Method of weighting can be reduced to minimum degree the impact of subjective factor.Determine that the method for weight has levels analytic approach, Principal Component Analysis Method, Fuzzy Inverse equation method, entropy assessment etc., what be wherein most widely used is analytical hierarchy process.Adopt comprehensive weight herein, namely the weight that entropy assessment and analytical hierarchy process obtain is combined, to obtain more reasonably evaluation result.

Above by reference to the accompanying drawings to invention has been exemplary description; obvious specific implementation of the present invention is not subject to the restrictions described above; as long as have employed the improvement of the various unsubstantialities that method of the present invention is conceived and technical scheme is carried out; or design of the present invention and technical scheme directly applied to other occasion, all within protection scope of the present invention without to improve.

Claims (7)

1. an insulator contamination Fuzzy Assessment Method, is characterized in that, comprises the steps:

Step one: set up insulator contamination state comprehensive fuzzy evaluation index system, selects two to pass judgment on project, i.e. intrinsic factor and environmental factor, then sets up the index system of a judge project;

Step 2: divide opinion rating, determine the set that evaluation result forms, for the index system of the project of judge, is obtained the Evaluations matrix of object to be evaluated by evaluation result set, and carries out standardization to more large more excellent type index and more little more excellent type index;

Step 3: the weight utilizing entropy assessment and the given evaluation index of analytical hierarchy processwherein, 0 < < ω_g< < 1 and${\mathrm{\&Sigma;}}_{g=1}^N{\mathrm{\&omega;}}_g=1,$$H_g=-{\mathrm{K\&Sigma;}}_{K=1}^M{f}_{kg}{\mathrm{lnf}}_{kg},$K＝1/lnM,$f_{kg}=r_{kg}/{\&Sigma;}_{k=1}^M{r}_{kg},$Wherein, H_g∈ [0,1], and regulation, work as f_kgwhen=0, f_kglnf_kg=0;

Step 4: the opinion rating in conjunction with index system divides, provide the membership function between each watershed area, then assess by the pollution flashover state of a jth judging quota to insulator of i-th item layer, the degree of membership set of opinion rating is the assessment result to evaluation index.

2. insulator contamination Fuzzy Assessment Method according to claim 1, it is characterized in that, in described step one index system of intrinsic factor comprise insulator retting-flax wastewater, run the breakage of the time limit and insulator, chap, aging, hydrophobic nature situation, the index system of environmental factor comprises pollution severity of insulators situation, meteorological condition, temperature and humidity.

3. insulator contamination Fuzzy Assessment Method according to claim 1, it is characterized in that, in described step 2, opinion rating adopts 5 grades to make energy, the pollution flashover situation of insulator is divided into " outstanding ", " well ", " qualified ", " attention " and " seriously ".

4. insulator contamination Fuzzy Assessment Method according to claim 3, is characterized in that, the described standardization processing method to more large more excellent type index is:i=1,2 ..., m; J=1,2 ..., n; Carrying out standardization processing method to more little more excellent type index is:i=1,2 ..., m; J=1,2 ..., n.

5. insulator contamination Fuzzy Assessment Method according to claim 1, it is characterized in that, the middle-level analytic approach of described step 3 is analyzed, to two-level index the relation between insulator and each influence factor, with affiliated first class index for criterion compares between two, Judgement Matricies.

6. insulator contamination Fuzzy Assessment Method according to claim 1, is characterized in that, in described step 4, membership function adopts triangle and half trapezoidal distribution function.

7. insulator contamination Fuzzy Assessment Method according to claim 1, it is characterized in that, described evaluation method also comprises step: adopt weighted mean Fuzzy Model for Comprehensive, retains main judging quota to the evaluation of insulator contamination state and single judging quota to the evaluation of insulator contamination state.