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A Proactive Group Maintenance Policy for Continuously Monitored Deteriorating Systems: Application to Offshore Wind Turbines

Shafiee, Mahmood, Finkelstein, Maxim (2015) A Proactive Group Maintenance Policy for Continuously Monitored Deteriorating Systems: Application to Offshore Wind Turbines. Proceedings of the Institution of Mechanical Engineers, Part O: Journal of Risk and Reliability, 229 (5). pp. 373-384. ISSN 1748-006X. (doi:10.1177/1748006X15598915) (Access to this publication is currently restricted. You may be able to access a copy if URLs are provided) (KAR id:79795)

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This article presents an optimum proactive group maintenance policy for continuously monitored systems affected by stochastic deterioration (degradation). A system is composed of multiple nonidentical subsystems, each exposed to a gradual degradation phenomenon. When the length (or size) of degradation in a subsystem reaches a predetermined fault threshold, it fails and leads to failure of the whole system. In order to avoid system failures and to improve availability levels, a proactive group maintenance task is conducted once the degradation level of a subsystem exceeds an “alert” threshold (smaller than the fault threshold). In this maintenance task, the critical subsystem undergoes a state-dependent repair action, and a preventive maintenance is performed on the other subsystems. Furthermore, the whole system is preventively replaced because of safety requirements when its operational age attains a fixed value. We formulate a multivariate nonlinear maintenance optimization model to simultaneously determine the optimal alert thresholds for subsystems and the replacement time for system. The performance of the proposed maintenance policy, regarding the objective of minimum system’s average long-run maintenance cost per unit time, is compared to five conventional cases of maintenance policies: the reactive response, individual age-based, individual condition-based, bivariate age- and condition-based, and age-based group maintenance. A numerical example, using real-life data collected from an offshore wind dataset, is presented to illustrate the applicability of the proposed model to the maintenance of a group of wind turbine bearings.

Item Type: Article
DOI/Identification number: 10.1177/1748006X15598915
Uncontrolled keywords: Proactive maintenance; Deterioration (degradation), Condition-based maintenance, Fault threshold, Operational age, Preventive maintenance
Subjects: T Technology > TA Engineering (General). Civil engineering (General) > TA165 Engineering instruments, meters etc. Industrial instrumentation
T Technology > TJ Mechanical engineering and machinery
V Naval Science > VM Naval architecture. Shipbuilding. Marine engineering
Divisions: Divisions > Division of Computing, Engineering and Mathematical Sciences > School of Engineering and Digital Arts
Depositing User: Mahmood Shafiee
Date Deposited: 27 Jan 2020 10:54 UTC
Last Modified: 17 Aug 2022 11:02 UTC
Resource URI: (The current URI for this page, for reference purposes)
Shafiee, Mahmood:
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