Risk assessment of high voltage insulator contamination condition by cloud theory
Ruqi Li · Power System Protection and Control · 2012
According to the characteristics of only considering the fuzziness and ignoring the randomness of evaluation indices for insulator contamination condition fuzzy synthetic evaluation model,a new insulator contamination condition synthetic evaluation model is proposed based on cloud theory.The number of discharge pulse,operation periods,weather conditions,the temperature and the relative humidity are chosen as five characteristic parameters affecting insulator condition,and the evaluation indices system is established.The cloud membership function which is composed of the expected value,the entropy,and the hyper entropy is used to describe the fuzziness and the randomness of the grade limit value for insulator condition synthetic evaluation,which softens the grading range.Clustering analytic hierarchy process is used to obtain subjective weighting,the variable weighting is determined by modifying the subjective weighting based on balancing the evaluation indices.On this basis,the coefficient of credible degree is defined,and the model not only obtains the result of synthetic evaluation but also provides the credibility information of the evaluation result.The practicality and effectiveness of the model is demonstrated by the results of actual numerical example.