An Increment Transfer Matrix Method for the Torsional Vibration Response of Steam Turbo-Generator Shaft System

2010 ◽  
Vol 34-35 ◽  
pp. 1082-1087 ◽  
Author(s):  
Cheng Bing He ◽  
Cheng Xing ◽  
Jian Shen
Keyword(s):  
Transfer Matrix ◽  
Torsional Vibration ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Short Circuit ◽  
Nonlinear Differential Equations ◽  
Mass Model ◽  
Shaft System ◽  
Turbo Generator ◽  
Generator Unit

In order to solve nonlinear system torsion response of turbo-generator unit, an increment transfer matrix method based on step-by-step integration method and traditional transfer matrix method was put forward. The method can be directly used to analyze nonlinear differential equations. Combined with Riccati method, the increment transfer matrix method was used in a multi-mass model. And matrix equations calculating the responses of torsional vibrations were deduced. Torsional vibration resulted from the faults of short circuit and asynchronous synchronization of 600MW steam turbo-generator unit were discussed in this work by using the increment transfer matrix method which can also extend the application of transfer matrix method in nonlinear field.

Study on the Coupled Bending and Torsional Vibrations of Turbo-Generator Unit with Rub-Impact

2012 ◽  
Vol 246-247 ◽  
pp. 1273-1277
Author(s):  
Cheng Bing He ◽  
Shi Chao Wang
Keyword(s):  
Transfer Matrix ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Vibration Amplitude ◽  
Critical Speed ◽  
Torsional Vibrations ◽  
Mass Model ◽  
Mass Unbalance ◽  
Turbo Generator ◽  
Generator Unit

An increment transfer matrix equations based on step-by-step integration method and traditional transfer matrix method are deduced Combined with multi-mass model and Riccati method, the increment transfer matrix method is put forward, that can be directly used to analyze the dynamic response of the coupled bending and torsional vibrations of turbo-generator shafts with rub-impact. Taking a turbo-generator unit as example, the vibration character of rub-impact fault is analyzed when unit starts up. The research results show that rubbing will make vibration amplitude increase when the rotational speed is lower than the first critical speed; however, when the speed is higher than the first critical speed, rubbing will make the rotor mass unbalance reduce, thereby vibration amplitude will reduce slightly.

scholarly journals Torsional Vibration of a Shafting System under Electrical Disturbances

2012 ◽  
Vol 19 (6) ◽  
pp. 1223-1233 ◽  
Author(s):  
Ling Xiang ◽  
Shixi Yang ◽  
Chunbiao Gan
Keyword(s):  
Transfer Matrix ◽  
Torsional Vibration ◽  
Simulation Analysis ◽  
Short Circuit ◽  
Lumped Mass ◽  
Concentrated Mass ◽  
Dynamical Equations ◽  
Mass Model ◽  
Two Phase ◽  
Turbo Generator

Torsional vibration responses of a nonlinear shafting system are studied by a modified Riccati torsional transfer matrix combining with the Newmark-βmethod. Firstly, the system is modeled as a chain consisting of an elastic spring with concentrated mass points, from which a multi-segment lumped mass model is established. Secondly, accumulated errors are eliminated from the eigenfrequencies and responses of the system's torsional vibration by this newly developed procedure. The incremental transfer matrix method, combining the modified Riccati torsional transfer matrix with Newmark-βmethod, is further applied to solve the dynamical equations for the torsional vibration of the nonlinear shafting system. Lastly, the shafting system of a turbine-generator is employed as an illustrating example, and simulation analysis has been performed on the transient responses of the shaft's torsional vibrations during typical power network disturbances, such as three-phase short circuit, two-phase short circuit and asynchronous juxtaposition. The results validate the present method and are instructive for the design of a turbo-generator shaft.

A System of Calculation and Analysis of Torsional Vibration for Turbine-Generator Shafts

2007 ◽  
Author(s):  
Dongmei Du ◽  
Zhi Zhang ◽  
Qing He
Keyword(s):  
Power System ◽  
Electric Power ◽  
Transfer Matrix ◽  
Torsional Vibration ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Electric Power System ◽  
Torsional Angle ◽  
Good Precision ◽  
Turbine Generator

Due to the disturbance of electric power system or other shock load, the torsional vibration of turbine-generator shafts occurs. Alternative shear stress due to torsional vibration decreases the shafts life, even results in shafts broken. It is significant to calculate and analyze natural properties and the responses of tosional vibration excited by the disturbance of electric power system in order to analyze and prevent catastrophic accident. The calculation and analysis system of torsional vibration of turbine-generator shafts is developed. With multi-mass lumped model, the model of torsional vibration of turbine-generator shafts is obtained. The system calculates the natural frequencies and the modal shapes of torsional vibration with the transfer matrix method, the response of torsional vibration of shafts with the increment transfer matrix method, such as torsional angle, angular velocity, angular acceleration, cross-section torque, and torsional stress. The response spectrum of torsional vibration can be obtained by fast Fourier transform algorithm Take an example of a 200MW turbine-generator, which is in the condition of non-all-phase operation. The responses of torsional vibration of shafts are calculated and analyzed. The bolt broken reasons of the coupling of inter-pressure rotor and low-pressure rotor and the coupling of generator and exciter are discussed. The results are identical with the data recorded in field. It is proved that the system is good precision, convenient using, friendly interfacing, and visual calculating.

Application of Transfer Matrix Method to Analysis of Transient Response of Beam

1987 ◽  
Vol 109 (3) ◽  
pp. 248-254 ◽  
Author(s):  
Moriaki Goya ◽  
Takuo Hayashi ◽  
Koichi Ito ◽  
Hiroshi Ohki
Keyword(s):  
Transfer Matrix ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Nonlinear Differential Equations ◽  
Effective Means ◽  
Linear Equations ◽  
Elastic Beam ◽  
Transient Responses ◽  
Concentrated Mass ◽  
Finite Difference Equations

The transient responses of an elastic beam to large dynamic deformations were analyzed numerically, using the transfer matrix method. Geometrically nonlinear differential equations were linearized by introducing increments of unknown functions, and the resulting linear equations were approximated by finite difference equations. A field transfer matrix was introduced for the analyses of large deformations; this determined the relationship between the incremental state vectors at both ends of the elastic segments. The Newmark β formulation was chosen to approximate the equation of motion for concentrated masses. A concentrated mass point transfer matrix and an inhomogeneous vector were introduced for analyses of the transient responses of the beams. A superposition scheme for the transfer matrix method was proposed as an effective means of obtaining a solution satisfying the boundary conditions at both ends of the beam.

Dynamic characteristics of coupling shaft system in tufting machine based on the Riccati whole transfer matrix method

2016 ◽  
Vol 231 (2) ◽  
pp. 356-371 ◽  
Author(s):  
Shuang Huang ◽  
Xinfu Chi ◽  
Yang Xu ◽  
Yize Sun
Keyword(s):  
Transfer Matrix ◽  
Dynamic Characteristics ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Natural Frequencies ◽  
Mode Shapes ◽  
Complex Dynamic ◽  
Rotor Systems ◽  
Machine Type ◽  
Shaft System

Focusing on tufting machine type DHUN801D-400, the complex dynamic model of coupling shaft system is built by using Riccati whole transfer matrix method, and the natural frequencies and mode shapes are analyzed. First, the components of coupling shafts system in tufting machine are introduced. Second, the structures of coupling shafts system are discretized and simplified. Third, the transfer matrix is constructed, the model is solved by using Riccati whole transfer matrix method, and then natural frequencies and mode shapes are obtained. Finally, the experimental results are quoted to demonstrate the applicability of the model. The results indicate that the Riccati whole transfer matrix method is well applicable for modeling the dynamics of complex multi-rotor systems.

Torsional Vibration Dynamic Analysis of the Test Rig for Intersecting Axes Gears of Helicopters

2011 ◽  
Vol 42 (11) ◽  
pp. 3-8
Author(s):  
Xiangyang Jin ◽  
Li Gui Xian ◽  
Zhao Yong Qiang
Keyword(s):  
Dynamic Analysis ◽  
Transfer Matrix ◽  
Torsional Vibration ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Test Rig ◽  
Vibration Load ◽  
Beveloid Gears ◽  
Vibration Dynamics ◽  
The Mathematical Model

In this paper, the transfer matrix method has been employed to analyze the torsional vibration dynamics of the test rig for closed intersecting axes beveloid gears of helicopter. The torsional vibration dynamic model has been established through adopting the transfer matrix method. At the same time, the mathematical model of the branch nodes and the dynamic analysis of test rig closed system have been also derived. The dynamic simulation principle of the test rig is studied and the corresponding dynamic load coefficients are also solved. Finally, the simulation curve of the vibration load coefficients of the test gears under different speed is drawn. The results shows that both the dynamic character of test rig and the loading precision can meet the test requirement.

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