Research on NOFRF Entropy-Based Detection Method for Early Damage of Pillar Porcelain Insulator

Hanling Mao,Xinxin Li,Hanying Mao,Weili Tang,Zhenfeng Huang,Yingxiang Huang

doi:10.1155/2020/2841254

Hanling Mao, Xinxin Li + Show 4 more

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https://doi.org/10.1155/2020/2841254

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Abstract

The pillar porcelain insulator is an important protection device that is related to the safety of the entire power grid. Small damage of it may even cause a disaster. Nonlinear output frequency response functions (NOFRFs) can well reflect the nonlinear characteristics of early damage in the system. This paper uses the NOFRF entropy-based harmonic excitation detection method to detect the damage of the structure. Its effect has been verified by using metal specimens. Then, the pulse hammer detection and harmonic detection are carried out to detect the early-stage damage of the pillar porcelain insulator, and they achieve a good result, which verifies that the harmonic detection method can detect the early-stage damage in the pillar porcelain insulator as well. In addition, the orthogonal test of the simulated breathing crack model is used to search the greatest influence of the parameters of crack on the detection index. Through the orthogonal analysis, the results show that among the lengths, positions, and angles of the crack, the length of crack is the main factor that affects the detection index.

Highlights

Academic Editor: Giuseppe Ruta e pillar porcelain insulator is an important protection device that is related to the safety of the entire power grid
Nonlinear output frequency response functions (NOFRFs) can well reflect the nonlinear characteristics of early damage in the system. is paper uses the NOFRF entropy-based harmonic excitation detection method to detect the damage of the structure
Its effect has been verified by using metal specimens. en, the pulse hammer detection and harmonic detection are carried out to detect the early-stage damage of the pillar porcelain insulator, and they achieve a good result, which verifies that the harmonic detection method can detect the early-stage damage in the pillar porcelain insulator as well

Summary

Introduction

Academic Editor: Giuseppe Ruta e pillar porcelain insulator is an important protection device that is related to the safety of the entire power grid Small damage of it may even cause a disaster. Rough the experiment, the analysis results show that the pulse hammer detection and proposed damage detection indexes have a good performance for indicating the degree of fatigue damage, especially the index which used the concept of information entropy. Liu et al [23] proposed a variable weighted contribution rate of NOFRFs, which is sensitive to the slight misalignment of the rotor system When it comes to online monitoring, the shortcomings of the pulse hammer detection method are revealed. A large number of repeated detections should be done to reduce the error

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Discussion

Conclusion