An opportunistic maintenance policy for offshore wind farms

Abstract

An opportunistic maintenance policy for offshore wind farms is introduced, considering imperfect maintenance and the weather window effect. Each wind turbine is regarded as a multi-component system divided into several assemblies. When one unit fails or reaches its critical degradation state, there is an opportunity to implement preventive maintenance for the others, reducing the losses of accidental failures. On the basis of the rolling horizon approach, the system condition is updated after the completion of a maintenance activity. By selecting the optimized maintenance combination at every opportunity, the maintenance plan over the mission period is finalized. The uncertainty of maintenance effectiveness and the costs of the time waiting for a weather window are also considered. Failure information is collected from existing literature to accomplish the calculations. Calculated results indicate that the proposed approach is beneficial to save the maintenance expenditure of offshore wind farms.