Applied Mechanics and Materials Vols. 496-500

Abstract: A study is made about the structure and its mathematical model of FT-PMM. The design of the vector control system (SVPWM) based on the id = 0 control strategy is proposed, which realizes the closed-loop vector control with feedback of speed, current, and position. This method is proved right by Matlab simulation. From a hardware level, the dsPIC30f4011 is used as the core of the system. With the help of the design of the bootstrap power supply of IR2110, the number of power is reduced and the cost is saved. The inverter circuit consists of 3 independent H bridges was used to control each wingding independently in order to enhance the ability of fault tolerance. Through hardware test, the result indicates that this vector control system could satisfy the demands of speed control and stable operation. After Man-made fault is set, the fault-tolerant performance is analyzed and the system is proved to have fault-tolerant capability to a certain extent.

Abstract: Quasi-homogeneous lean mixture combustion technology can take full advantages of lean-combustion, and help reduce the engine fuel consumption and emissions. Quasi-Homogeneous Lean-burn engine Control System, combined virtual instruments with engine electronic control technology, can precisely control air-fuel ratio injection, timing, fuel injection pulse and ignite on timing, which provides a reliable and convenient platform for the engine lean-burning performance tests..

Abstract: With the development of the aviation industry, the aircraft's increasingly high performance requirements, the overall application of thin-walled structural components became more widespread. However, due to the complex structure parts, thin wall, high precision machining process was complexity, the cutting force, cutting heat, clamping force under the influence of other factors, prone to machining distortion, and with the lower part wall thickness, decreased in rigidity, it was difficult to ensure processing quality. In this paper, we proposed several effective aviation thin-walled parts machining precision control program to solve the problems in the processing of machine structural characteristics of thin-walled parts .The results of experiments and production practice proved that these methods effectively control the air thin-walled parts machining precision machining to meet quality requirements, while reducing the processing time, improve processing efficiency, it was convenient and efficient processing methods.

Abstract: Spatial curved blades have been widely used in major aerospace manufacturers due to their light weight, high structural efficiency, high reliability, etc. However, their processing deformation, processing difficulty, and so on limit their use. In order to deal with the situation, flexible multi-point auxiliary supporting fixture for the processing of spatial curved thin-walled parts has become a major topic of current researches. The layout of positioning and clamping points of the flexible multi-point fixture direct affects the stiffness of clamping positions on the thin-walled parts to be processed. When cutting force is definite at a certain point in machining, the greater the stiffness at the processing positions on the part, the smaller the processing deformation due to the cutting force. Therefore, in order to reduce the machining deformation due to the poor stiffness, a suitable positioning and clamping layout is needed to improve the surface stiffness at the machining positions. Thus, the machining quality of thin-walled parts can be improved.

Abstract: The component of drive system for Electric vehicle is analyzed,and torque control strategy of motor is proposed. The design scheme of controller based on brushless direct current motor and dedicated control chip of motor TMS320LF2407A is presented. The main controller and hardware circuits of driving part is designed,and software control program is proposed,The test result shows that the design scheme proposed has high feasibility.

Abstract: In order to decrease the exhaust of the switch of inverter bridge arm, the auxiliary resonant net was imbed in the circuit structure which lead to cost ascension and credibility descend. This text discusses to design a DC/AC converter based on simplex single voltage source high frequency chain inversion technology, the output is 0.9KW/115V/400Hz.The pulse direct current voltage has been created by forward circuit and absorption branch which is controlled by voltage feedback in the input terminal of inverter bridge arm. The soft-switch of inverter bridge arm using DPM has been realized by controlling open or close of switch electric circuit on the invert bridge arm at pulse voltage for zero stages. It is not adding topology complicated degree of main circuit which could assure the reliability of the inverter.

Abstract: Body static stiffness is an important index to evaluate the vehicle performance, and test is a main evaluation method for the static stiffness. Accordance with the existed problem of static stiffness measurement, we developed a bending and torsion stiffness measurement system. The system includes loading device, test bench, displacement sensor and fixture, data-acquisition system and software. The software communicates with slave computer (PLC) through serial interface to make data process and store. It also could do stiffness analysis according to relative methods. Practical application shows that the system could measure the static stiffness accurately.

Abstract: Based on the theory of electromagnetic compatibility, in view of the automatic loading control system, and carries on the EMC design, analyzed the sensitive circuit part of the principle and method of EMC design, mainly includes the power supply part, CPU control chip, the digital interface circuit and D/A conversion circuit protective measures.

Abstract: Based on the simulation model of hydraulic servo non-sinusoidal vibration control system by MATLAB/Simulink,the paper analyzed the degree of the best performance under different types of load disturbance on the crystallizer PID control System, and discussed the influence the amplitude and frequency of load disturbance on the control system. It has certain theoretical guiding significance for practical production.

Abstract: Nowadays, the development of Power Electronics is very quickly. High frequency switching power supply has been widely used in many fields because of its advantages, such as high efficiency, low volume and low cost etc. this paper focuses on the research of DC-DC transform technology in switching power supply. In the foundation of the traditional forward converter, an active clamp forward converter based on one-cycle control is designed. The control IC is IR1150 based on one cycle control technique. The results show that the converter can effectively eliminate the interference of power ripple and switch error. The control method is simple and reliable. The peripheral circuit is easy to realize.