On design, modelling, and analysis of a 10‐MW medium‐speed drivetrain for offshore wind turbines

Abstract

The design of a medium‐speed drivetrain for the Technical University of Denmark (DTU) 10‐MW reference offshore wind turbine is presented. A four‐point support drivetrain layout that is equipped with a gearbox with two planetary stages and one parallel stage is proposed. Then, the drivetrain components are designed based on design loads and criteria that are recommended in relevant international standards. Finally, an optimized drivetrain model is obtained via an iterative design process that minimizes the weight and volume. A high‐fidelity numerical model is established via the multibody system approach. Then, the developed drivetrain model is compared with the simplified model that was proposed by DTU, and the two models agree well. In addition, a drivetrain resonance evaluation is conducted based on the Campbell diagrams and the modal energy distribution. Detailed parameters for the drivetrain design and dynamic modelling are provided to support the reproduction of the drivetrain model. A decoupled approach, which consists of global aero‐hydro‐servo‐elastic analysis and local drivetrain analysis, is used to determine the drivetrain dynamic response. The 20‐year fatigue damages of gears and bearings are calculated based on the stress or load duration distributions, the Palmgren‐Miner linear accumulative damage hypothesis, and long‐term environmental condition distributions. Then, an inspection priority map is established based on the failure ranking of the drivetrain components, which supports drivetrain inspection and maintenance assessment and further model optimization. The detailed modelling of the baseline drivetrain model provides a basis for benchmark studies and support for future research on multimegawatt offshore wind turbines.

Drivetrains on floating offshore wind turbines: lessons learned over the last 10 years

“…In a study by Wang et al [17] sensitivity of the drivetrain fatigue damage to varying fidelity in the bedplate modeling was studied. A 10 MW medium speed drivetrain [18] installed on a spar type floating wind turbine was used in this study. The results -as shown in Fig.…”

“…This paper presents a synthesis of the results of several own studies over last ten years addressing the above questions. For theoretical studies, the 5 and 10 MW reference drivetrains have been employed for comparative studies, [11,18]. The field experiences from operation of the world's first floating farm have also been used in this study.…”

Response to Reviewer 2

“…We also agree that more literature pertaining to the modelling of wind turbine main bearings would strengthen this piece of work and this will be included in the updated manuscript. This will include ref [2][3][4][5][6][7] among others.…”

Constructing fast and representative analytical models of wind turbine main bearings

“…This in turn effects technology design and selection and puts pressure on original equipment manufacturers (OEMs) and operators to improve turbine reliability. As such, reliability and failure rate considerations have received much attention in the literature (Tavner et al, 2007;Wilkinson, 2011;Artigao et al, 2018).…”