Imbalance–misalignment–rubbing coupling faults in hydraulic turbine vibration

Fu, Xiangqian; Jia, Wenjue; Xu, Hongyang; Song, S.L.

doi:10.1016/j.ijleo.2016.01.006

Cited by 21 publications

(11 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As far as shafting system vibration is concerned, the research on vibration characteristics gradually develops from single vibration under a single excitation to multi-directional vibration under the influence of the coupled vibration sources. Such as the differential equation of lateral vibration of the shafting is established, and the bifurcated characteristics of the vibration caused by rotor mass eccentricity and rotor speed of the HTGU are revealed [19,20].…”

Section: Symbolmentioning

confidence: 99%

Stability and Sensitivity Analysis and Optimization Control of the Hydro-turbine Generator Unit

Shi

Zhou

2021

Preprint

View full text Add to dashboard Cite

The hydro-turbine governing system (HTGS) and shafting system are mutually coupled. However, the interaction between them has always been neglected. This paper aims to explore the stability and sensitivity of the governor control parameters to the HTGS and shafting system and make the optimal control of the stable operation for the hydro-turbine generator unit(HTGU). First, a novel HTGU motion equation is proposed, which can make connections between the HTGS and the shafting system of the HTGU. And on this basis, the nonlinear coupling mathematical model of the HTGS and the shafting system is established. According to the nonlinear mathematical model, the sensitivity of the governor control parameters on the operating stability of the HTGU is obtained. Then, a multi-objective governor control parameters optimization strategy is proposed. Furthermore, the chaotic-dominated sorting genetic algorithm II(NSGA-II) and multi-objective evolutionary algorithm based on decomposition(MOEAD) were introduced to obtain the optimal control parameter and mutually verify the effectiveness of the optimization effect. Finally, the nonlinear dynamic characteristics of HTGU under optimal control were revealed. The simulation results show that the rotation speed deviation and shafting system vibrations are sensitive on the PID parameters in some ranges and the stable region will be decreased when considering the shafting system vibrations. The multi-objective PID parameter optimization strategy shows good control performance on the nonlinear dynamic characteristics of the HTGU. The shafting system vibrations excited by the coupled vibration sources are quasi-period in 3D space. In addition to this, these results and the optimization strategy can provide some bases for the design and stable operation of the HTGU.

show abstract

Section: Symbolmentioning

confidence: 99%

Stability and Sensitivity Analysis and Optimization Control of the Hydro-turbine Generator Unit

Shi

Zhou

2021

Preprint

View full text Add to dashboard Cite

show abstract

“…In the field of nonlinear dynamic modeling of multi-stage gear system, the coupling fault models of unbalance, misalignment and friction [12] of double rotor system [13], rigidly coupled rotors system [14] and motor-flexible coupling-rotor system [15] have been established. For the dynamic study of coupling characteristics, the coupling vibration analysis of flexible structure of gear system [16], the dynamic coupling between time-varying meshing stiffness (TVM) and gear [17], strength coupling [18], and the nonlinear dynamic effect of clearance change on fault coupling [19] have been carried out.…”

Section: Introductionmentioning

confidence: 99%

Analysis of coupling fault correlation and nonlinear vibration of multi-stage gear transmission system

Zhao¹,

Wang²,

Li³

et al. 2020

J. vibroeng.

View full text Add to dashboard Cite

In the multistage gear transmission system, when multiple faults are coupled, the faults with weak signals are often hidden and hard to identify. Multi-fault coupling may also cause new coupling fault characteristics, such as new peaks or side bands in the spectrum. These characteristics are likely to contain fault information. Studying the sources of frequency components in coupled fault signals will help to decouple the signals and dig out the correlation characteristics between faults. The coupling fault of fixed-axis gear crack and planetary gear tooth broken was studied in this paper. The nonlinear dynamic model of the multi-stage gear transmission system was used for simulation, and the fault frequency characteristics of the system varying with the excitation frequency were obtained. The short-time Fourier transform (STFT) and waterfall plot analysis were applied to the experimental signals to separate the fault features. By comparing the theoretical and experimental signals, we found the natural frequency of the system, the side frequency characteristics of single fault and coupling fault, and the cause of new peaks. This study has a guiding significance for the separation and identification of coupling faults of the multi-stage gear transmission system.

show abstract

“…The range extender has a complex structure and many sources of excitation. According to statistics, more than 60% of faults in rotating machinery systems are related to rotor misalignment [4]. Misalignment of the motor shafting will cause abnormal vibrations of the unit, and the vibration will also accelerate the abrasion of the winding insulation layer and induce stator short-circuit faults [5,6].…”

Section: Introductionmentioning

confidence: 99%

Dynamics Analysis of Misalignment and Stator Short-Circuit Coupling Fault in Electric Vehicle Range Extender

Feng

Wang

et al. 2020

Processes

View full text Add to dashboard Cite

Due to the complex structure and wide excitation of the range extender, the misalignment and stator short-circuit coupling fault can easily occur. Therefore, it is necessary to study the coupling fault mechanism of the range extender, analyze the cause of the fault and the fault evolution law, and research the coupling fault characteristics. To reveal the mechanism of misalignment and stator-short-circuit coupling fault, the misalignment mechanism was analyzed and the bending and torsion electromagnetic stiffness of the generator in the stator short-circuit fault was derived. Then the dynamic model of bending and torsion coupling for the generator was established. Furthermore, we used the Runge-Kutta method to study the vibration response characteristics of generator rotor under coupling fault. Then through finite element analysis, the feasibility of coupled fault diagnosis was verified. The results show that the response of the generator rotor not only has the frequency component of single faults, but also new frequency components such as 4.0 and 6.0 harmonic amplitudes of radial vibration and 3.0 harmonic amplitudes of torsional vibration, respectively.

show abstract

Imbalance–misalignment–rubbing coupling faults in hydraulic turbine vibration

Cited by 21 publications

References 5 publications

Stability and Sensitivity Analysis and Optimization Control of the Hydro-turbine Generator Unit

Stability and Sensitivity Analysis and Optimization Control of the Hydro-turbine Generator Unit

Analysis of coupling fault correlation and nonlinear vibration of multi-stage gear transmission system

Dynamics Analysis of Misalignment and Stator Short-Circuit Coupling Fault in Electric Vehicle Range Extender

Contact Info

Product

Resources

About