Reliability analysis of composite insulators subject to multiple dependent competing failure processes with shock duration and shock damage self-recovery

• Published in: Reliability engineering & system safety Vol. 204; p. 107166
• Main Authors: Kong, Xuefeng, Yang, Jun
• Format: Journal Article
• Language: English
• Published: Barking Elsevier Ltd 01.12.2020; Elsevier BV
• Subjects: Composite insulators; Damage assessment; Degradation; Demand analysis; Failure analysis; Impact damage; Insulators; Multiple dependent failure processes; Recovery time; Reliability analysis; Reliability engineering; Reliability model; Self-recovery mechanism; Shock; Shock damage model; Shock duration; Multiple dependent failure processes; Reliability model; Composite insulators; Shock duration; Shock damage model; Self-recovery mechanism
• ISSN: 0951-8320; 1879-0836
• DOI: 10.1016/j.ress.2020.107166

•The single shock process is specified by shock duration and shock magnitude.•A shock damage model is proposed to describe the impact of shocks on degradation.•A detail self-recovery process is given to depict the self-recovery mechanism.•A new reliability model is derived for the reliability assessment of insulators.•The numerical study shows the effectiveness of the proposed reliability model. Recent developments in composite insulators highlight the demand for reliability analysis, and similar to most engineering products, composite insulators experience multiple dependent competing failure processes. However, two distinct characteristics of the failure processes of composite insulators—sustained shock and self-recovery mechanism—have not received attention in previous studies, resulting in inaccurate assessments of their reliability. In view of these problems, a novel shock damage model is first proposed to accurately reflect the impact of harmful random shocks on the degradation processes of composite insulators, considering both the shock magnitude and the shock duration. Subsequently, a detailed self-recovery process considering both the recovery level and the recovery time is developed to reflect the self-recovery mechanism. Furthermore, an improved practical reliability model with an analytical expression is proposed for composite insulators subject to multiple dependent competing failure processes considering degradation processes, random shocks, and self-recovery processes. Finally, a numerical study of composite insulators is conducted to illustrate the implementation of the proposed model.