Dynamic characteristics and experimental study on a wind turbine gearbox

다국어 초록 (Multilingual Abstract)

A gearbox is part of the transmission chain of wind turbine, which can increase rotational speed and reduce torque. Dynamic characteristics of the gearbox directly influence the vibration and the service life of the wind turbine system. In this paper, dynamic behaviors of a megawatt level wind turbine gearbox are studied theoretically and experimentally by dividing the gearbox into a transmission sub-system and a body sub-system. The transmission sub-system, i.e., the gear-shaft-bearing sub-system, is coupled with the gearbox body using bearings which are simulated as mass-less springs. The theoretical study applies a finite element model for the gearbox, where the internal excitations are caused by time-varying stiffness, transmission errors and mesh impacts. The time-varying wind load is considered as the external excitation, collected by a remote real-time online test and transformed into load spectrums through the rain-flow counting method. With boundary conditions and working conditions being defined in the finite element model, the natural characteristic analysis and the dynamic response analysis are conducted. Results show that the operating frequencies of the gearbox are far away from the main natural frequencies of the system, thus avoiding resonances. The main vibration components of the gearbox are with meshing frequencies of the second and third gear stage and their multiplication counterparts. Moreover, the greatest vibration occurs at the bearing housing of the high-speed shaft with the root-mean-square value of its vibration speed less than 3.5 mm/s. A test rig is developed and the experimental vibration conditions are monitored by acceleration sensors. The experimental results are in accordance well with the theoretical results.
In this way, the theoretical model is validated. The methodology reported in this paper can provide valuable guidance for practical industrial engineers.

참고문헌 (Reference)

1 A. C. Goncalves, "Vibration and wear particles analysis in test stand" 59 (59): 209-216, 2007

2 J. Parra, "Two methods for modeling vibrations of planetary gearboxes including faults : Comparison and validation" 92 : 213-225, 2017

3 S. Eberabach, "The investigation of the condition and faults of a spur gearbox using vibration and wear debris analysis techniques" 260 (260): 16-24, 2006

4 C. Brecher, "Stiffness and load free transmission error for the multi-flexible-bodydynamics (MFBD) Simulation of a wind turbine gearbox using a FE-based tooth contact analysis" 1-6, 2008

5 X. Liu, "Resultant vibration signal model based fault diagnosis of a single stage planetary gear train with an incipient tooth crack on the sun gear" 122 : 65-79, 2018

6 Z. Caichao, "Research on dynamical characteristics of wind turbine gearboxes with flexible pins" 68 (68): 724-732, 2014

7 Z. Cai-chao, "Remote real-time online testing and evaluation for a megawatt level wind turbine gearbox" 31 (31): 17-22, 2012

8 J. Helsen, "Multi-body modeling of varying complexity for modal behavior analysis of wind turbine gearboxes" 36 (36): 3098-3113, 2011

9 J. Pears, "Investigation of methods to predict parallel and epicyclic gear transmission error" SAE 2005

10 J. D. Smith, "Gear noise and vibration-second edition revised and expanded" Marcel Dekker, Inc 2003

11 L. Hui, "Gear fault diagnosis based on amplitude and demodulation during run-up" 27 (27): 8-11, 2008

12 D. Qin, "Flexible multi-body dynamic model of coupled planetary gear and bearing" 2009 : 280-287, 2009

13 Z. Feng, "Fault diagnosis for wind turbine planetary gearboxes via demodulation analysis based on ensemble empirical mode decomposition and energy separation" 47 : 112-126, 2012

14 A. R. Varkonyi-koczy, "Fast anytime fuzzy Fourier estimation of multiline signals" 58 (58): 1763-1770, 2009

15 J. Zierath, "Experimental identification of modal parameters of an industrial 2‐MW wind turbine" 21 (21): 338-356, 2018

16 Shuaishuai Wang, "Effects of gear modifications on the dynamic characteristics of wind turbine gearbox considering elastic support of the gearbox" 대한기계학회 31 (31): 1079-1088, 2017

17 C. Zhu, "Effect of flexible pin on the dynamic behaviors of wind turbine planetary gear drives, Proceedings of the Institution of Mechanical Engineers" 227 (227): 74-86, 2012

18 Hongfei Zhai, "Dynamic modeling and analysis for transmission system of high-power wind turbine gearbox" 대한기계학회 29 (29): 4073-4082, 2015

19 Caichao Zhu, "Dynamic analysis of the drive train of a wind turbine based upon the measured load spectrum" 대한기계학회 28 (28): 2033-2040, 2014

20 Caichao Zhu, "Dynamic analysis of a megawatt wind turbine drive train" 대한기계학회 29 (29): 1913-1919, 2015

21 X. An, "Application of the ensemble empirical mode decomposition and Hilbert transform to pedestal looseness study of direct-direct-drive wind turbine" 36 (36): 5508-5520, 2011

22 S. H. Kia, "Analytical and experimental study of gearbox mechanical effect on the induction machine stator current signature" 45 (45): 1405-1415, 2009

23 J. L. M. Peeters, "Analysis of internal drive train dynamics in a wind turbine" 9 (9): 141-161, 2005