Abstract: This paper presents a new type of anti-upsetting equipment, which is used to avoid upsetting of axle-end in wheelset disassembly and assembly. The special structure of the equipment can transmit the cylinder’s pressure to the axle-end rationally and eliminate eccentric-loaded or partial stress concentration on the section of the axle-end. The anti-upsetting equipment has been analyzed and verified with the finite element software. This new type of anti-upsetting equipment is applied on an automatic wheelset disassembly and assembly machine to ensure the anti-upsetting on axle-end.
Abstract: The phenomenon of buckling is attributed to the non-uniform stress imposed on strip. This paper investigates the occurrence of this non-uniform by calculating the stress distribution in circumferential and axial direction. The results indicate that stress distribution is even in circumferential direction, and the non-uniform happens in the axial direction. Furthermore, this non-uniform is quiet related to the proportion of strip width and the roll flat part length. Meanwhile, the roll flat part length should as long as it could be in the context of insuring the enough centripetal force to prevent the snaking.
Abstract: This paper analyzes the problems of artificial potential fields in robot path planning. A hybrid algorithm for robot path planning is proposed. Robot searching for path in artificial potential fields method, it is possible that the robot can’t reach the goal because of local minimum, when it is best to use a genetic algorithm for robot. Simulation results show the effectiveness of the models, and it can effectively solve the problem caused by defects of artificial potential fields in the path planning.
Abstract: According to the problem of low energy utilization of plane spiral coil used in micro-ICP, a kind of micro stereo helical coil was designed. Made 24 different structural parameters of stereo spiral coil whose diameter range 3~10 mm. Using comprehensive experimental method tested different parameters’ coils inspire argon plasma. In 13.56MHz RF power, relationships between argon pressure, coil turns, coil diameter and combustion /maintaining power of micro-ICP excitation source were tested. From spectrometer observed 17 argon emission spectrum in 690~860 nm. Spectral lines intensity influenced by RF power and work pressure. Experiments proved that micro-ICP excitation source using stereo helical coil is feasible. It can form Ar plasma and inspire Ar spectral lines.
Abstract: In this study, blind source separation (BSS) method was applied to separate the multi-channel fault vibration signals generated by a rotor. As the signals were non-stationary, an algorithm based on spatial time-frequency distributions was applied to the experimental vibration signals to obtain the non-stationary vibration sources that were mutually independent. Further, AR modeling estimates of these sources were calculated with BURG method. A neural network was applied to the AR modeling parameters to perform the fault classification. The separation results of an experiment on a rotor’s multi-fault show that this method is feasible for fault diagnosis.
Abstract: For various problems in the procedure of high-power induction motor’s starting and disadvantages of traditional starting methods, this paper proposed a new type of full-voltage starting method of high-power induction motor—a full-voltage starting method with dynamic reactive power compensation, introduced its principle, studied the control strategy of full-voltage starting with dynamic var compensation emphatically, and established the simulation model for direct starting, soft starting and full-voltage starting with dynamic var compensation based on the Matlab/Simulink simulation software to do digital simulation and compared three methods. The simulation results indicated that the method proposed in this paper can make the high-power induction motor start fast and smoothly with both high-torque and low starting current, and it has a better starting performance than traditional starting methods and the advantage of not affecting power quality.
Abstract: Based on mean filtering with good denoising capability for white gaussian noise and wavelet transform with high frequency denoising and singularity detection capabilities, a new method combining mean filtering and wavelet transform is proposed for extracting weak periodic impact signal in heavy noise background. Three different thresholds of wavelet transform are used to extract feature. The simulation results show that the wavelet filtering with improved threshold has the best effect. The SNR(Signal to Noise Ratio) are greatly improved and RMSE(Root Mean Square Error) are greatly reduced.This method has an excellent effect on extracting weak periodic impact feature and has very strong practicability.
Abstract: The effect of stator and rotor subsection’s characteristic to the motor design and the performance established on the basis of the structure characteristic of submersible motor has been researched in this paper. The leakage reactance which is caused by the magnetic isolated segment has been calculated by solving the three-dimensional magnetic field, the ingenuity design of rotor sheet displays a skew slot role. Some methods such as Simpson’s algorithm, layered algorithm has been used in the calculation of part of the submersible motor, so the design method has been improved. An imitation experiment model machine has been designed and manufactured on the basis of this. This method was proved to be right and practicable by comparison of design result with experiment data.
Abstract: Submersible motor is of lathy subsection structure of stator and rotor and the leakage reactance in subsection impact on motor performance. Three-dimensional finite element mathematic model of submersible motor magnetic isolated segment used to calculate leakage reactance corresponding to the leakage magnetic field in it is established in this paper. Simulation prototype is designed. The accuracy and feasibility of the method described here is directly verified by example comparison. This leakage reactance has bigger influence to performance parameter of the motor and must be taken into account in the design of submersible motor for the future.
Abstract: In recent years, the proportion of the wind power in the grid is increasing rapidly. In addition, the penetration of wind power in grid has been rising. It will lead adverse effect to grid, if the wind turbine off-grid during the fault of network. Wind power technology-leading countries have issued the quantitative standards of fault through which requires on-line operation .In this paper, the influence of wind turbines off-grid on the grid and turbines during the fault of grid is analyzed firstly. Meanwhile, the control objective of the low voltage ride through (LVRT) is proposed. Several types of LVRT technology for the Permanent Magnetic wind Power System are summarized and evaluated respectively. Finally, the developing direction of this technology is drawn from the above discussion.