Function
Ensures there is no interruption to transmission from electrical failures or structural problems with the offshore platform.
Who supplies them
High voltage electrical contractors such as ABB, Alstom, GE, Schneider Group and Siemens Power Transmission and Distribution.
Offshore contractors such as Deutsche Windtechnik, Petrofac
Key facts
Maintenance and service of the offshore substation primarily consists of non-intrusive inspections of topside switchgear and transformers, sampling of transformer oil, foundation and topside structural inspection and resulting infrequent service interventions.
The owner carries out paint repairs and secondary steelwork repairs (for example to railings, gratings, gates, stairs and ladders).
Serious repair operations, such as replacing transformers, require heavy lift vessels.
Rapid turnover parts and consumables are stored in a large warehouse at the onshore base.
Back-up diesel generators require periodic maintenance and refuelling.
Access to the substation may be by vessel or helicopter but since few failures require urgent attention, the weather downtime of vessels may not be an important consideration, as it is for turbines. During planned power outages to support detailed inspection and service operations, careful planning is required to ensure weather windows are used to avoid excessive wind farm downtime if work cannot be completed and assets re-energised.
Onshore substation maintenance comprises non-intrusive inspections of switchgear, transformers and any reactive power compensation equipment. Infrequent service in response may be required.
Unlike many of the systems of an offshore wind farm, the onshore substation is almost entirely non-offshore wind specific – consisting of standard high-voltage electrical equipment.
What’s in it
- Inspection
- Maintenance and service record management