This is the first edition of CAN/CSA-IEC 61400-11, Wind turbines - Part 11: Acoustic noise measurement techniques, which is an adoption without modification of the identically titled IEC (International Electrotechnical Commission) Standard 61400-11 (third edition, 2012-11). For brevity, this Standard will be referred to as CAN/CSA-IEC 61400-11 throughout.
This Standard replaces the previous edition, published in 2007 as CAN/CSA-C61400-11, Wind turbine generator systems - Part 11: Acoustic noise measurement techniques (adopted IEC 61400-11:2002 + A1:2006). At the time of publication, IEC 61400-11:2012 is available from IEC in English only. CSA Group will publish the French version when it becomes available from IEC.
This part of IEC 61400 presents measurement procedures that enable noise emissions of a wind turbine to be characterised. This involves using measurement methods appropriate to noise emission assessment at locations close to the machine, in order to avoid errors due to sound propagation, but far away enough to allow for the finite source size. The procedures described are different in some respects from those that would be adopted for noise assessment in community noise studies. They are intended to facilitate characterisation of wind turbine noise with respect to a range of wind speeds and directions. Standardisation of measurement procedures will also facilitate comparisons between different wind turbines.
The procedures present methodologies that will enable the noise emissions of a single wind turbine to be characterised in a consistent and accurate manner. These procedures include the following:
- location of acoustic measurement positions;
- requirements for the acquisition of acoustic, meteorological, and associated wind turbine operational data;
- analysis of the data obtained and the content for the data report; and
- definition of specific acoustic emission parameters, and associated descriptors which are used for making environmental assessments.
This International Standard is not restricted to wind turbines of a particular size or type. The procedures described in this standard allow for the thorough description of the noise emission from a wind turbine. A method for small wind turbines is described in Annex F.