starts on 21 January, 2019 ends on 11 February, 2019
Should the US TAG vote to approve the proposal to divide IEC 61400-4 ED2: Design requirements for wind turbine gearboxes" into four separate documents?
At the last JWG 1 – Wind Turbine Gearboxes meeting with ISO /TC 60 in Shanghai, China, 23-24 October 2018, the structure of IEC 61400-4 ED2 was discussed and it was agreed by joint working group to recommend a division of the document into four separate documents.
The table below describes the proposed division and the motivation for the proposed changes.
Proposed project number
IEC 61400-4 Ed.2
Design requirements for wind turbine gearboxes
IEC/TS 61400-4-1 Ed.1
Reliability assessment of drivetrain components in wind turbines
JWG 1 concluded that the methods for reliability assessment are not mature enough for inclusion into an International Standard. Therefore, reliability assessment is proposed as a Technical Specification, for the industry to get acquainted with the method and gather experience of its correlation with field experience.
The word “components” is chosen in the title for paving the way towards an extended scope in following editions of the TS from gearbox to the complete drive system. For instance, the bearing equations could immediately be applied for generator bearings.
IEC/TR 61400-4-2 Ed.1
Lubrication of drivetrain components in wind turbines
The lubrication chapter of IEC 61400-4 Ed.1 is comprehensive, but contains very few requirements. JWG 1 therefore reasoned that such recommendations are better covered in a Technical Report.
The word “components” is chosen in the title for paving the way towards an extended scope in following editions of the TR. For example, some provisions for gearbox lubrication may 1:1 apply for oil lubricated main bearings or generator bearings. Further, some experts in JWG 1 have expressed an interest for including grease lubrication in following editions of the TR.
IEC/TR 61400-4-3 Ed.1
Explanatory notes on IEC 61400-4 – Sup-portive information for wind turbine gearbox design
IEC 61400-4 Ed.1 contains extensive explanation and recommendations, which was found necessary back in the days for improving turbine knowledge of gearbox designers, and help turbine designers understand gearbox challenges. Experience in the application of Ed.1 shows however that those recommendations are frequently misinterpreted as additional requirements.
JWG 1 has evaluated the respective clauses and annexes, and conclude that they are still valuable and should hence not be deleted. Instead, JWG 1 suggests to move them into a Technical Report which both explains some of the backgrounds for the requirements in the main standard, and supports system designers in the use of IEC 61400-4 Ed.2.
NOTE: The proposed project numbers are provisional numbers and subject to changes depending on the outcome of restructuring activities taking place in the 61400 series (to be submitted to and endorsed by TC 88).
National Committees are invited to vote on the proposed division of IEC 61400-4 ED2 into four separate parts.
IEC national committees are requested to send their vote to the IEC electronic voting / commenting system
by 2019-02-22 at the latest.
NOTE: US TAG ballots must be submitted at least two weeks earlier to allow for resolution of any comments prior to the IEC deadline.