Towards component reliability testing for marine energy converters

• Published in: Ocean engineering Vol. 38; no. 2; pp. 360 - 370
• Main Authors: Thies, Philipp R., Johanning, Lars, Smith, George H.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-02-2011; Elsevier
• Subjects: Applied sciences; Component reliability; Component testing; Converters; Direct power generation; Energy; Energy of waters: ocean thermal energy, wave and tidal energy, etc; Exact sciences and technology; Failure rates; Fatigue failure; Marine; Marine energy converter; Mooring; Natural energy; Reliability; Service simulation testing; Simulation; Tanks; Component testing; Reliability; Marine energy converter; Service simulation testing; Mooring; Energy convertor; Service; Experimental study; Accelerated test; Case study; Marine environment; Renewable energy; Simulation; Failure analysis; Energy of waters; Component
• ISSN: 0029-8018; 1873-5258
• DOI: 10.1016/j.oceaneng.2010.11.011

The dearth of generally available, failure data that can be directly applied to marine energy converters (MECs) has been commented on for some years. The advancement of the industry will be fundamentally linked to proven reliability assessments, which is difficult on an industry wide basis. This paper describes how targeted component reliability testing could enable the establishment of relevant failure rate data for the marine renewable energy industry. The necessity of dedicated component testing is briefly reviewed for the wave energy sector together with the experience from other industries. A generic procedure used in test intensive industries for service simulation testing is outlined and applied to wave tank mooring tests. By means of a rainflow analysis procedure and the Palmgren–Miner rule the most severe load cycles, largely contributing to the fatigue damage are identified and reproduced for a possible component test signal. The application of the suggested generic test approach will assist marine energy stakeholders in obtaining evidence of component reliability under simulated operational conditions much more rapidly than can be achieved with prototypes under normal service conditions. Importantly, this would also allow a more accurate estimate of field failure rates and could reveal possible failure modes/design weaknesses ahead of field deployments.