Wei Nan Zhu

Vibration Test of Bearing Ball Fatigue Testing Machine Based on VB

Ball bearing life test, once the failure specimen ball fatigue, if not timely shutdown, will lead to a series of chain reactions caused by the fault processing is not seasonable, serious word may also lead to the damage of equipment. Therefore the vibration test is very important to accurately determine the specimen failure, ball. In this paper, the vibration test for bearing fatigue testing machine, the test results to be real-time and accurate judgment sample ball failure.

Modal Analysis and Application Based on Finite Element Method

Mode is the natural vibration characteristics of the mechanical structure. Each mode has the specific natural frequency, damping ratio and modal shape. These modal parameters can be obtained by the calculation and experimental analysis. A calculation or test analysis process is called modal analysis. The analysis process is achieved if calculated by the finite element method, is called the analysis of calculating mode. The spindle mode of driving roll was analyzed in this paper. If clear structure in one easy frequency affected range of each order main modal characteristics through modal analysis method, it can predict the vibration response of this band structure of external or internal variety under the action of vibration. Therefore, the modal analysis is an important method for fault diagnosis of structure dynamic design. Comparing theory results with finite element results indicated that the error was less than 10 percent. The accuracy on the shaft modal analysis finite element method was improved.

Statics Analysis on Workbenches of Three Kinds of Electromaglev Linear Feed Unit

Based on the disciplines theory such as the mechanics and electromagnetics, this paper presents three kinds of electromaglev linear feed unit, with the help of the 3D modeling software Solidworks and large general purpose finite element analysis software ANSYS. The statics analysis on workbenches of the three kinds of electromaglev linear feed unit are made by using of ANSYS, then the results are analyzed and compared. It can be identified as the conclusion that, the structural stiffness on workbenches of the three kinds of magnetic linear feed unit can basically meets the requirement, and all of them can be selected as the needed structural design. But the four-L separately suspended and oriented type electromaglev linear feed unit has the better structure stiffness, and take the weight, cost, load capacity and dynamic characteristics and other factors into account, we preferred to choose the workbench design of the four-L-pillar separately suspended and oriented type electromaglev linear feed unit.

Correlated and Coherent Analysis Based on Vibration Data of Fatigue Life Test Rig for Ball with Three Point Contact

The exciting input signals of the parts in a fatigue life test rig for ball with three point contact and the system’s output signals were analyzed by auto-correlation and cross-correlation with MATLAB software, which eliminated the impact of noise to a certain extent and got the response signals of same frequencies caused by exciting input signals. Finally, the result showed that the text rig was linear by coherent function analysis, which provided the theory basis for modal and dynamic analysis further.

Finite Element Analysis to Ceramic Ball Pure Rolling Contact Stresses

The RCF (Rolling Contact Fatigue) life of bearing balls is a main method, to evaluate the performance of bearing materials and their production technology. In general, The RCF life of ceramic balls is a reliable technique to asses whether or not they are suitable to be used in rolling bearings. The RCF life of ceramic balls is depend on contact stresses chiefly. It applies the finite element analysis to calculate the surface stresses and subsurface stresses, including 1st principal tensile stresses and shear stresses. The theory results are compared with the finite element solutions. Very good agreement is observed. The finite element results in this paper have an important applied value. The results provided theoretical basis for rolling contact fatigue life prediction of the ceramic balls.

The Modal Analysis of the Ceramic Ball’s Rolling Contact Fatigue Tester’s Drive Shaft

The Modal Analysis of the Ceramic Ball Rolling Contact Fatigue Life Test Rig Drive Shaft Abstract: With the increasing of the rolling contact fatigue life tester’s speed, the vibration problem is getting more and more serious. In order to optimize the dynamic performance test rig, the modal analysis of the drive shaft was carried. First the vibration mechanics model was got by simplifying the shaft and get the first order of horizontal natural frequency which is 787.4266Hz with the theoretic algorithm. Then the drive shaft’s modal analysis was made by using the finite element software and that is 779Hz. The relative error between the former and the latter is 1.1%. It has demonstrated the accuracy of the finite element result, and its modal analysis could be the basis of the dynamic optimization.

Finite Element Analysis of Radial Bearing Magnetic Field

There is a magnetic field inside of the radial bearing. The magnetic field distribution is one of the key factors that decides the running state and performance of the system. By using the finite element ANSYS software, the magnetic field of radial bearing was analyzed. The analysis indicated that NSSN mode is suiTable for magnetic radial bearing and NSNS mode unsuiTable. There is a magnetic coupling between magnetic poles. There is magnetic leakage for radial bearing, which leaks towards spindle center through rotor and to coil, but it is very little, less than 5%. The research provides a theoretical basis for optimization of system structure and controller design.

Devise of the RCF Test Rig for Ceramic Bearing Ball by Design Methodology

It is presented to apply the designing methodology in design of an accelerated pure rolling contact fatigue test rig for ceramic bearing ball. Starting with function analysis, the request and structure of test rig are analysed. Meanwhile, the form matrix table is established, from which many designing schemes can be obtained. In accordance with several kinds of innovation schemes, the appraised decision of product is analyzed. The specimen machine is made according to the design scheme in the design of innovation.

Simulation of Vector Control Strategy of PMSM Based on MATLAB

In the fields of numerical control machine, robot etc, vector control system of permanent magnet synchronous motor (PMSM) has widely application prospects. Proportion integration (PI) adjustment block, coordinate transformation block, space vector pulse width module (SVPWM) block and the simulation model of the whole system are built in MATLAB/SIMULINK according to the mathematical model, SVPWM technique and vector control theory of PMSM. The simulation results show that stator winding triphase current can run smoothly, speed and output torque can be accurately follow the given value. The results provide the basis for further research of the performance of the PMSM control system.

Simulation and Experiment Based on the Mixed Robust Optimal and H∞ Controller of PMLSM

There are many uncertain sensitive issues such as parameter disturbance and edge effect when PMLSM running. In order to solve these problems, a method called mixed robust optimal and H controller is presented. Robust optimal and H∞ control strategy is made use to design the mixed robust optimal and H controller of PMLSM. Large external disturbance and internal nonlinear perturbations can well be eliminated by this controller, and it’s easy to be practiced. MATLAB/SIMULINK is made use to simulate the system. With the help of PMAC board and COPLY controller permanent brushless motor controller, hardware test platform is built. The test results show that mixed robust optimal and H controller has strong robustness and traceability compared with traditional PID control method.