共查询到20条相似文献，搜索用时 218 毫秒
1.
On the basis of a planetary transmission, a novel hydrodynamic speed controlled transmission system for wind turbines with large capacity is presented. The new drive train consists of wind rotors, planet accelerators, hydro-mechanical and synchronous generators. The dynamic mathematical model of the drive train is established. The digital simulation of speed regulation characteristics for hydrodynamic speed controlled system is studied by using Matlab/Simulink. The simulation results show that continuously variable transmission and fixed speed control can be achieved, and the drive train works well in stability and dynamic performances. They can increase the power yield from the wind, smooth the electric power output, and alleviate the load peak in the new drive train . 相似文献
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Considering that the transmission system of wind turbine works in complex and changing load environment caused by stochastic wind speed,this paper uses sparse least squares support vector machine(SL-SVM) to simulate wind speed of true wind field,and obtains time-varying wind load caused by stochastic wind speed. The lumped-parameter method is used to develop a dynamic model of planetary gear transmission system of wind turbine coupled with bearing. The model includes the varying wind load,time-vary mesh stiffness of gear pair and time-vary stiffness of rolling element bearing. The numerical method is used to simulate the dynamic performance of planetary gear system of Multibrid Technology Wind Turbine with 1.5 MW rated power. The vibration displacement responses of the transmission system are obtained as well as dynamic meshing force each pair of gear and nonlinear bearing forces. The research can provide a foundation for optimizing dynamic performance and reliable design of gear transmission system of wind generator. 相似文献
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针对行星齿轮减速器工作过程中传递功率的频繁变化容易导致其运动状态发生突变的问题,探讨行星齿轮传动系统随传递功率的分岔特性。基于2K-H型行星齿轮传动系统纯扭转非线性动力学模型,采用CPNF(continuous Poincaré-Newton-Floquet)方法研究了传递功率对行星齿轮传动系统周期运动稳定性的局部精细分岔规律,运用直接数值积分的方法绘制了系统随功率的全局分岔图,并对两种仿真结果进行了对比。结果发现,在某些参数组合下,行星齿轮传动系统会共存几个稳定或不稳定的周期轨道;当功率在196~220 kW范围内,随着功率值的逐渐增大,行星齿轮传动系统的各种形态的周期轨道均是通过倍周期倒分岔的途径在相应功率分岔点处发生稳定性突变的;在轻载工况下(传递小功率),行星齿轮非线性系统容易呈现混沌运动状态。 相似文献
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Dynamic characteristics of multi-stage planetary gear trains in shield machine cutter drive 
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下载免费PDF全文 A purely torsional dynamic model of multi-stage planetary gear trains is developed to investigate the dynamic characteristics of the transmission system in shield machine cutter drive. In the model,phase difference between mesh stiffness and error among each stage caused by different initial mesh positions is considered,and other factors such as component bearing stiffness,time-varying mesh stiffness and error are considered as well. Inherent characteristic analysis shows there are more unique and diverse vibration modes in multi-stage planetary gear trains than in single-stage planetary gear trains. Through dynamic response analysis,time-domain and frequency-domain response of dynamic meshing force of each stage is obtained. As the frequency of exciting force of medium-speed and high-speed stage is in proximity to the natural frequency of the system,harmonic resonance tends to occur,which needs to be paid great attention to. Dynamic factors of each stage are also computed and prepare the ground for the dynamic optimizing design of planetary gear trains. 相似文献
5.
Powertrain parameter design for the electric vehicle with taking the energy consumption of air conditioner into consideration 下载免费PDF全文
下载免费PDF全文 On the basis of considering the influence of air conditioner on vehicle performance,the parameter determination of the power train composed of a battery,a traction motor and a two-speed transmission of an electric car is carried out. To ensure the economy of operation,a shifting strategy with a principle which emphasizes the high work efficiency of the power train is drawn up and the gear ratios are corrected aiming at the least energy cost over the drive cycle. The simulation results indicate that the designed parameters meet the requirements moderately and the driving range is extended by 5.28% when the air conditioner is turned off and 4.29% when turned on,compared with the initial results through the correction of the gear ratios. 相似文献
6.
Since the wind turbines are installed on the flexible support tower, the drive train of the wind turbines runs under severe work conditions with varying wind directions and loads. So its failure rate is high and it is the bottle neck of the wind power development. This work presents a study which takes the coupling effect of oscillating of tower barrel and the twisting vibration of driven train into account. Using the lumped parameter method, a coupled dynamic model for the megawatt wind turbine drive train is built by considering the flexible tower barrel support effects. Then, the dynamic characteristics of the megawatt wind turbine drive train are analyzed. The Campbell chart is used in this research to analyze the potential resonance points. And the potential resonance frequencies between the cutting in and cutting out rotational speed of the drive train are obtained. Finally, Simpack is used to analyze the dynamic characteristics of drive train and verify the correctness of the proposed method. 相似文献
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The study object of this paper is helical beveloid gears with parallel axis. Based on the gear Mshing Principles and the tooth-surface equations of pinion and gear,the mathematical model of tooth contact is developed under standard installation and installations with center distance error,axis error and multiple error respectively. The MATLAB solver is used to obtain the contact trace and the transmission error under different installing conditions and the comparative analysis is made. The results indicate that this gear drive is sensitive to axis installation errors,it forms the edge contact and cause the periodic transmission error. It can provide the foundation for designs and analysis of this gear transmission. 相似文献
8.
The current cycloid reducer drive has the shortage of needing special output mechanism, large volume and high vibration. To solve this problem, a new gyratory fixed spindle cycloid drive is designed. The drive principle of the reducer is introduced. Formula for calculating the basic parameters and tooth profile equation of cycloid gear are derived. On the basis of discussion of the mechanism and the principles of gear connection, a prototype is designed and manufactured. The results of the prototype test on the gear test rig indicate that the transmission efficiency of the new drive may reach 91.9% at rated operating conditions, the biggest vibration velocity effective value is 3.09 mm/s, and the biggest structure noise is 101.6 dB. 相似文献
9.
The dynamic behavior of railway bridges (dynamic deflection and acceleration) is one of the running safety control indices for high speed trains. Therefore, the dynamic behavior of railway bridges is studied based on the concept of the dynamic signatures of the train and the bridge. By simplifying the train excitation as a series of moving concentrated forces, the mathematical expressions of the dynamic signatures of the train are obtained through theoretical derivations, and then a method is presented for calculating the resonance speed of trains and the maximum vertical acceleration of the bridge. With this method, the dynamic responses of the simple supported bridge can be calculated quickly. The feasibility of this method is validated through some examples, in which the resonance mechanism of train bridge system and the influencing factors are investigated. In addition, the effect of high frequency components to the bridge acceleration is also analyzed. 相似文献
10.
Taking the sliding bearing into account, the lateral vibration analysis models of two single rotor were built respectively using the transfer matrix method. The transmission matrix of herringbone gear coupled unit is derived. Using whole transfer matrix method, the lateral torsional coupling analysis model of herringbone gear rotor system is set up, and the vibration characteristics of gear rotor bearing system in gas turbine is analyzed. Through numerical calculation and anlysis, the eigenvalue of gear rotor system, the Logarithmic decrement and the critical speed are obtained. The result shows that the working speed of this gear rotor bearing system is far away from the critical speed, therefore the system is stable and safe. 相似文献
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The double drive hoist reducer developed in the planetary gear is a new generation of energy saving and environment protecting hoist product. The multi flow transmission system theory of hoist is analyzed. With the theory and method of bond graph,a bond graph model with coupled vibration is established for hoist multi flow transmission system for the first time. The state equation of the system is developed and dynamic simulation analysis is also carried out. The internal changing law and relationship of the system for the state variable are got. Therefore, the dynamic properties and gearing features of this system are revealed comprehensively. The research results can provide the dynamic analysis method and design basis for multi flow transmission system of hoist. 相似文献
13.
Design of Self-adjusting Planetary Gear Rotation Mechanism Based on Planetary Gear Structures Muster
Self-adjusting planetary gear rational mechanism can eliminate the influence of various uncertain errors in mechanism. Therefore ,it's method of self-adjusting designing is attented by machine designer. For seeking a simple, regular, and widely realizing self-adjusting designing way, this article uses approach of the follow text to design no over-constraint and self-adjusting mechanism. First, the article advances the conception of planetary gear structure muster and it's plotting basis, through using for reference the strategy and method of self-adjusting structure groups in planar linkage mechanism. Second, it designs the self-adjusting planetary gear structure muster, through analyzing the constraint and freedom of planetary gear structure muster. Third, it designs the self-adjusting mechanism, through adding aptitude rotational links outside of self-adjusting planetary gear structure muster. This mechanism can realizes the self-adjusting in the interior of muster and self-adapting in the exterior of muster. This designing plan possesses a series of excellence, such as, theoretical, simple, feasible, widely self-adjusting. Consequently, the mechanism can eliminate the working capability influence of various errors. 相似文献
14.
随着我国果品加工业的迅速发展,水果清洗机的应用越来越广泛,为此,研制了一台轻便灵活、适用于中小型企业的喷刷式水果清洗机。介绍了该机结构特点、工作原理,以及水果清洗刷的清洗过程分析,确定清洗刷辊转速ω与出料翻斗转速n的关系。该机采用了带螺旋板和毛刷的清洗刷辊,采用蜗轮—蜗杆传动形式,运用出料翻斗将水果清洗后送出机体,具有启动平稳、工作可靠和效率高等特点,适合苹果、桃和红枣等水果的清洗加工。 相似文献
15.
Study on Surface Noise Distribution of Three ring Reducer 总被引：1，自引：0，他引：1
The three ring reducer is a kind of gear drive developed in the past decade. Adopting the new conception of "parallel and movable axis" of multiple mechanisms, this kind of gear drive has many characteristics such as large transmission ratio, high efficiency and so on. As the three ring reducer has been invented only for ten years, up to date the design of the gear drive is only made with analogue method, no design theory can be followed, there exist serious vibration and noise in transmission, which limit its wide application in industry. In this paper, the transmission principle of SHQ50 reducer is studied, the surface noise distribution of the reducer, transmission ratio 49.5 , is measured and analyzed by means of sound intensity method. The 3D distribution maps of noise on top of reducer, input side and output side of reducer, and left side and right side of reducer are drawn. With the sound intensity frequency maps of each measuring point, the sources of giving out noise are analyzed. The reducer of low vibration and noise can be designed rightly according to the analysis. 相似文献
16.
Mechanical analysis for the discrete teeth harmonic drive gear pair is carried out. The force on discrete teeth is calculated based on the deformation coordination equation,and the contact stress of meshing pair is obtained by Hertz equation. According to transmission periodicity of the discrete gear harmonic wave and the input angle values of continuous sampling wave generator,the distribution of discrete teeth harmonic drive meshing force and contract stress in rigid tooth profile,tooth wave generator and discrete teeth is obtained. By studying the top cutting phenomena in rigid tooth profiles,the change trend of meshing force and contact stress on the contact surface is found,and positions for high meshing force and high contact stress in transmission are also found,in order to provide reference for further intensity and structure optimization design. 相似文献
17.
This paper develops a generalized 3-dimensional 14-DOF dynamic model for hypoid gear which considers the time-varying friction coefficient and lubrication situation. We propose a mixed elastohydrodynamic lubrication(EHL) friction model of hypoid gear tooth contact to reflect the realistic lubricant situation in gear transmission system consisted of full film contact and asperity contact. Under the mixed lubrication condition, the effects of time-varying friction coefficient on gear dynamic is analyzed. The load sharing coefficient is used to calculate the instantaneous friction coefficient at each contact point along the contact path. Friction coefficient model based on mixed elastohydrodynamic lubrication(Mixed EHL) is incorporated into the dynamic model to predict the dynamic mesh force and transmission error with constant and time-varying friction coefficient. The simulation results under a wide range of speed and load show that the time-varying friction coefficient has a marginal effect on the dynamic response. 相似文献
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To address the problems of low carrying capacity and short life of bearings in current ring reducers, a new type of ring reducer is proposed which consists of a two stepped transmission. One is a planetary transmission, and the other is an N type planetary transmission with a low tooth number difference. Based on the analysis of structural features, the transmission principle, and a transmission load situation, a contact finite element model of the new type of ring reducer is set up, and the stress value and the actual pairs of meshing teeth are derived by calculation. Based on gear modification research theory, the second stage transmission gear pairs of the new reducer are modified on its teeth profiles. Results demonstrate that the load capacity of transmission gear pairs have been enhanced greatly. 相似文献
20.
The finite element model is developed for the multi stage planetary gearbox housing in shield tunnelling machine (STM), and the the eigenvalue problem is solved by using block Lanczos method, and then the low order natural frequencies and corresponding modes are extracted. Based on the theory of experimental modal analysis, the modal testing is made for the gearbox housing by pulse excitation method. The least squares complex frequency domain (LSCF) estimation method is used to analyze the modal data, and the natural characteristics of housing is obtained. According to the modal assurance criterion (MAC), the experimental modal parameters are validated. Modal analysis shows that the experimental data is coincided with analytical results, which indicates the accuracy of the theoretical model and testing method. The coupling sympathetic vibration is disappearing between the gears train and housing, the local vibration is large at the high speed side of gearbox housing, and the torsional mode is outstanding under operating condition. The research results provide theoretical basis and experimental support for the structural optimization of the gearbox of STM. 相似文献