Case study on VAWT certification

Alistair MackinnonOperations Manager Wind Energy

TUV SUD NEL Ltd(Formerly the UK’s National Engineering Laboratory)

Myres HillNational Wind Energy CentreNational Wind Energy Centre

(Supported by DECC & NMS)

‘The most important thing in communication is hearing what communication is hearing what

isn’t being said ….. ’

Accreditation(UKAS/A2LA etc)MLA

Landscape

TestingISO 17025

CertificationEN 45011/Guide 65

Standards

BWEA Standard

British Wind Energy Association Small Wind Turbine Performance and Safety Standard

29 February 2008

Section 2 Section 3 Section 4 Section 5Section 2Power

Performance

BS EN 61400-12-1:2006

Section 3Acoustic

Sound Testing

BS EN 61400-11:2003IEC 61400-14:2005

Section 4Strength and

Safety

BS EN 61400-2:2006

Section 5Duration

BS EN 61400-2:2006

Darrieus – H type

Wind Direction

Darrieus – Phi type

Darrieus – Delta type

Darrieus – Helical type

Savonius type

A A

Wind Direction

• Static loading – generally constant

• Cyclic loading – quasi static & dynamic cycling

• Stochastic loading – random variations

• Aerodynamic loading – force of the wind

• Mechanical loading – gravity, gyroscopic, transient

• IEC 61400-2: 2006 requires an aeroelastic approach

• No simplified load model for VAWTs hence no standard design filedesign file

• large number of load cases

• differences in the software implementation

• challenging for both the designer and CB – guidance is at best vague

• power performance issues – self start (savonius) or ‘motored’ up consequences for AEP

• issues in duration – net positive power flow….. • issues in duration – net positive power flow…..

• safety and function – dynamic behaviour observations

• supporting structure – currently excluded

• braking, shutdown and protection

• Power production• Power production plus occurrence of fault• Normal shut down• Emergency or manual shutdown

Aeroelastic load cases

• Emergency or manual shutdown• Parked (standing still or idling)• Parked and fault condition• Transport, assembly, maintenance and repair

‘The most important thing in communication is hearing what communication is hearing what

isn’t being said………… ’