Fibre optic sensors for dynamic cable condition monitoring in floating offshore wind turbines

Project Description

Power cables play a crucial role in enabling power transmission from floating offshore wind farms to the onshore grid. In particular, the dynamic power cables from floating offshore wind turbines (FOWT) to the seabed. These cables are continuously subjected to bending and twisting forces caused by external environmental forces, such as ocean currents, tides, waves and the behaviour of floaters. Therefore, these cables are highly likely to suffer mechanical damage. Any failure or damage to the power cables can cause an outage and significant economic loss. The existing state-of-the-art cable monitoring technologies primarily focus on the internal failure associated with partial discharge or distributed strain and temperature measurements via embedded fibre optics. However, these cable monitoring systems are slow and very expensive. Hence, it is crucial to have a fast, low-cost, multi-point sensing system to understand the dynamic cable behaviour when subjected to continuously changing external environmental forces. This knowledge will assist in monitoring in-situ dynamic power cables to allow predictive maintenance and also, aid in the design optimization of power cables, floater and their associated components. Herein, a novel approach will be investigated using multiple fibre Bragg grating arrays, a fast-optical switch and a unique signal processing algorithm for monitoring the strain in dynamic power cables, subjected to external loads. The proposed approach will be evaluated through experimental investigations and computational work.