Advanced Materials Research Vols. 383-390

Abstract: The performance of a doubly excited brushless machine (DEBM) with radially laminated magnetic barrier rotor (RLMB-rotor) is investigated by using the 2D transient finite element analysis model and the experimental method. The magnetic fields, the mutual coupling of the dual stator windings, the no-load characteristics and the electromagnetic torque characteristics of the sample machine are presented. The results of the experiment validate the theoretical analysis and simulation results.

Abstract: Electronic excitation temperature is an important indicator of the spectrometer excitation source. This work experimented self-made micro-ICP excitation spectroscopy based on PCB technology, and detected 17 spectral lines in 690~860 nm of argon atom. 763.51 nm and 772.42 nm spectral lines whose wavelengths are close to were used to calculate electronic excitation temperature of argon excited by micro-ICP, and results show in 1600~3000 K. Experimental test data shows effects of argon gas pressure on electronic excitation temperature that in 20~210 Pa electronic excitation temperature increases with pressure on the whole. When argon pressure is greater than 220 Pa, plasma flame flickers and the electronic excitation temperature shows greater fluctuation; Experimental test shows effects of RF power on electronic excitation temperature that in 3~23 W electronic excitation temperature gradually increases with RF power. Causes of electronic excitation temperature with pressure, RF power variation are analyzed.

Abstract: How the mechanical parameters of rock change with the development of joints and fractures is still a puzzle. It is hard to measure rock joints accurately at present. Resistivity is an important parameter of rock and its value can reflect the degree of fragmentation of rock. A new method combining measurement method of Young’s modulus with resistivity survey method is proposed in this paper. To determine the variation of mechanical parameters in the process of rock damage, the uniaxial, tri-axial compression tests and resistivity survey on rock specimens are done. The results showed that the values of resistivity were continuously increasing, but Young’s modulus and mechanical parameters were decreasing in the process of rock damage. The relationships between resistivity and mechanical parameters are established based on the experiments in the process of rock damage. Therefore, the damage state of rock and the change of mechanical parameters of rock can be determined according to the variance of resistivity. The study is helpful for design and real- time stability evaluation on rock engineering.

Abstract: Permanent magnet synchronous motor (PMSM) used for driving hybrid electric vehicle (HEV) have the characteristics of high power density, high efficiency, high reliability and good dynamic performance. However, it’s a very complex process for PMSM pulling into synchronization and it is difficult to analyze and calculate the starting and operating performance exactly, which would be very important for HEV application. So based on the requirement of HEV, a 30kw PMSM is studied. The 2D transient electromagnetic fields of this motor were calculated by using an improved finite element method. Starting performance was analyzed, and some parameters such as stator current and time-speed characteristic could be obtained. From the study on performance of machine with different ratio of spacing of damping bar (Lb) / stator pitch (Ls) in solid rotor and different number of damping bars in laminated rotor, that influence of rotor structure on starting process were studied. The calculated results show good agreement with the experimental data. Some reasonable conclusions were obtained, which could provide some help for the design of this kind of PMSM and the application of it in HEV.

Abstract: Induction motor is widely applied to people's lives and production. This paper presents the simple and sophisticated of some methods which are used to diagnose the rotor fault. After analyzing the advantage and disadvantage of these methods, this paper tells what the key of rotor fault diagnosis of induction motor is, and put forward a new method.

Abstract: This paper introduces working process of the once forming leaf-spring rolling mill, and specific to the problems that the two vertical rollers must realize synchronous control in the rolling process, puts forward the master-slave synchronous mode base on fuzzy control to achieve synchronous control. The various performance indicators of master-slave mode hydraulic synchronization control system are superior to the equivalence mode, and obtain satisfactory effect. Finally, fuzzy toolbox based on the MATLAB/SIMULINK simulates the systems respectively, and the simulation results prove the above conclusions.

Abstract: An oscillation model of a single free piston engine generator which is coupled with a linear generator is presented in this paper. Based on the dynamics and energy equilibrium, the oscillation model is described by the mass spring damping system. It demonstrates that the generator could be regarded as a single freedom self-exited vibration system. The excitation is the periodical combustion in the cylinder. And the system reaches a limit loop after several cycles. The frequency and amplitude characteristics with the effects of key variables are shown. It provides a power map as function of the stiffness and mass, which will be applied into the match design and optimization.

Abstract: The factors affecting regenerative braking performance of brushless DC motor(BLDCM) were analyzed by means of bench test and road test .the BLDCM was used as drive motor in a four –wheel-independent-drive EV. The relation between PWM duty and motor rotation speed, charging current and voltage were determined by test, which can benefit design of control strategy of regenerative braking for electric motor and help to improve energy efficiency.

Abstract: Depending on the mechanical characteristics of casing located at the bending part of sidetrack horizontal well, the calculation model of casing collapsing strength under the effect of bending load is established, and corresponding theoretical formulae is derived. During the process of deducing formulas, the influence of bending load on the casing section out of roundness is ignored, which made the calculation formula benefits intuition and practicality comparing to the T.Tamano formula. The result of this paper is verified through the simulation value and laboratory test of casing used in the Jilin oilfield. It shows that the formula of this paper can meet the engineering commands; the axial load is significant to affect casing collapsing strength, and in the actual production process should be strictly controlled.

Abstract: Adopting a new kind of transducer technology vibration cable technology, can round-guard in large region without bodyguard whole day, and using display and warning on the end equipments may judge abnormal conditions occurred in what time and in what place. The system makes use of quadratic and own source filter, suppress the disorder waves induced in transducer, install two-rank amplifier which kernel being operation amplifier, especially for micro-vibration originating undercut can judge illegal invader, and can judge the invaders are human or heavy equipment according to vibration intensities.