Open Access

ARTICLE

A Situational Awareness Method for Initial Insulation Fault of Distribution Network Based on Multi-Feature Index Comprehensive Evaluation

Hao Bai¹, Beiyuan Liu^2,*, Hongwen Liu³, Jupeng Zeng², Jian Ouyang⁴, Yipeng Liu¹
1 Electric Power Research Institute, China Southern Power Grid, Guangzhou, 510663, China
2 State Key Laboratory of Disaster Prevention and Reduction for Power Grid, Changsha University of Science and Technology, Changsha, 410114, China
3 Electric Power Research Institute of Yunnan Power Grid Co., Ltd., Kunming, 650032, China
4 Qujing Power Supply Bureau of Yunnan Power Grid Co., Ltd., Qujing, 655099, China
* Corresponding Author: Beiyuan Liu. Email:

Energy Engineering https://doi.org/10.32604/ee.2024.049848

Received 19 January 2024; Accepted 18 March 2024; Published online 19 April 2024

Abstract

Most ground faults in distribution network are caused by insulation deterioration of power equipment. It is difficult to find the insulation deterioration of the distribution network in time, and the development trend of the initial insulation fault is unknown, which brings difficulties to the distribution inspection. In order to solve the above problems, a situational awareness method of the initial insulation fault of the distribution network based on a multi-feature index comprehensive evaluation is proposed. Firstly, the insulation situation evaluation index is selected by analyzing the insulation fault mechanism of the distribution network, and the relational database of the distribution network is designed based on the data and numerical characteristics of the existing distribution management system. Secondly, considering all kinds of fault factors of the distribution network and the influence of the power supply region, the evaluation method of the initial insulation fault situation of the distribution network is proposed, and the development situation of the distribution network insulation fault is classified according to the evaluation method. Then, principal component analysis was used to reduce the dimension of the training samples and test samples of the distribution network data, and the support vector machine (SVM) was trained. The optimal parameter combination of the SVM model was found by the grid search method, and a multi-class SVM model based on 1-v-1 method was constructed. Finally, the trained multi-class SVM was used to predict 6 kinds of situation level prediction samples. The results of simulation examples show that the average prediction accuracy of 6 situation levels is above 95%, and the perception accuracy of 4 situation levels is above 96%. In addition, the insulation maintenance decision scheme under different situation levels is able to be given when no fault occurs or the insulation fault is in the early stage, which can meet the needs of power distribution and inspection for accurately sensing the insulation fault situation. The correctness and effectiveness of this method are verified.

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Keywords

Distribution grid; insulation degradation; initial insulation fault; multi-feature indices; multi-class SVM; situational level; situational awareness

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