Applied Mechanics and Materials Vols. 397-400

Abstract: Magnetic field, produced by magnetomotive force (MMF) harmonic waves, is harmful to motors, by reducing efficiency of motors, resulting in demagnetization of permanent magnets and so on. It is also responsible for the increase of eddy current loss and the rise of temperature of rotors. Thus, research on the influence of pole-slot match on MMF with concentrated fractional-slot winding is necessary. This paper aims at researching unit motors with different cooperation of slots and poles. First, basic principle of MMF is described. Then, with different kinds of unit motors, MMF of harmonic waves is analyzed. Based on these analyses, distributive regularities are summarized.

Abstract: This paper combines hardware reliability and software mobility with modern intelligent control through the analysis of the control object using intelligent decoupling control scheme to control the pressure control system of the large gas collector in coke oven. By using expert control strategies based on the DCS, the paper develops the system design which is versatile and effective.

Abstract: It is a new method of pipeline detection that pipe detector based on laser. This paper introduces the laser inner diameter detector related principle, detail the state of development and the latest development of pipe detector based on laser designed and made by domestic and international companies, and contrastive analysis the function of pipe detector. The paper proposed development prospect and the main technical difficulties of the pipeline laser detector. The development direction of pipeline laser detector is high efficiency, high precision and high speed. However, the key technical difficulties of in pipe detector based on laser, such as centering problem, reliability and accuracy problem, data analysis and processing problems. Keywords:Pipeline; Laser; Detector; Inner diameter;

Abstract: Design a step motor control system based on Field Programmable Gate Array (FPGA). Give the hardware circuit of this system and the program based on very high speed integrated circuit hardware description language (VHDL). Compared to step motor control system based on single chip microcomputer, the processing speed of this system is faster.

Abstract: With the rapid development of domestic economy and the construction, the application of 10 kV power system is more and more extensive and the environment of the application is also more and more complicated. Aiming at this situation, in this paper, a new-type circuit breaker is proposed for the outer environment, which is based on the Water pressure up case configuration. The configuration is fully-enclosed, small size, light-weight, and it is applicable to high temperature and humid areas. In order to study characteristics of the permanent magnetic force (PMA), the paper adopts the electromagnetic analysis software ANSOFT to analyze its static and dynamic characteristics. The experiment results show that the performance of PMA is reliable. In order to analyze the insulting property of its enclosure design with new-style and small size, ANSOFT electric field is adopted to conduct simulation analysis and the experiment results show that the design and improvement measure are stable and reliable.

Abstract: Vacuum heat treatment furnace temperature parameter is a large time delay, nonlinear,time-varying and complex control objects, Single-chip computer is used as the control core to achieve the temperature control through the fuzzy control algorithm, the hardware structure an software design process are given in this paper, the control precision, dynamic characteristics, and optimization of the performance are improved by this control system.

Abstract: Alternating current (AC) machine speed-adjusting system plays a very important role in our daily life. Firstly, this paper studies the basic principle of vector control system for three-phase asynchronous motor based on the MT coordinate system, and this paper especially gives the calculation principle diagram of the current model for rotor flux. Then this paper establishes the double closed-loop vector control system based on the Matlab/Simulink detail, and gives the simulation results. The simulation results of the double closed-loop vector control system verify the correctness of the simulation models and the principle of vector controlling.

Abstract: For the characteristic of the MMS series Thermo-Mechanical Simulator hydraulic control system, using traditional PID control method can not achieve the desired control effect. Basing on genetic algorithm, BP neural network, which has the arbitrary non-linear approximation ability, self-learning ability and generalization ability, has been used into the hydraulic control system to achieve the online adjustment of the weighting coefficients and the adaptive adjustment of PID control parameters. The results of simulation and online tests show that the control effect of hydraulic system has been improved significantly, and the accurate control of hydraulic system hammer displacement has been realized.

Abstract: According to the features of high sensitivity, integration, measurement accuracy of MPU-6050 MEMS sensor, this paper design a parameters acquisition and display system based on STM32 and LabVIEW for vehicle driving attitude detection. The host computer adopts LabVIEW as a development platform which display the data collected by sensor and the vehicle attitude image. Propose a variable-weights complementary filtering algorithm to fuse the data collected by sensor. Compensating the dynamic error, obtain more accurate vehicle attitude angles.

Abstract: In order to rapidly develop the control system of the Electromechanical Actuator (EMA), the DSP development platform is established using rapid prototyping method based on the MATLAB software, and all the models is configured and researched. First, the DSP development platform structure in the environment of MATLAB is mainly presented. And the operation principle has been showed. Then, the EMA control circuit board schematic diagram is necessarily introduced, which one is for the developer to conveniently configure the system model. Finally, the developer reasonably configures the control system models used in the Simulink library and constitutes them to speed closed loop control system of the EMA. The EMA control system code will be compiled and debugged rapidly through this platform. The executed program will automatically download into the DSP processor. And the result of debugging would be sent to the CAN bus receiver. For generally speaking, the difficulty of EMA control system code development method is reduced and the development cycle is shortened using this rapid prototyping method. And this system development method is fast and effective.