Applied Mechanics and Materials Vols. 291-294

Abstract: The steady voltage theory of permanent-magnet generator with pressure roller is analyzed, permanent-magnet with the high remanence intensity is adopted, generator’s structure is designed with creativity, and output voltage is increased at low rotate speed of generator. Using the parallel electronic voltage stabilizer stabilizes output voltage at high rotate speed, and solves vehicle’s permanent-magnet generator’s problem of generating stable voltage at wide speed and wide load.

Abstract: The paper analyzes the process characteristics of mechanical and electrical products' industrial design, and emphasizes that products' industrial design adequately use more methods in premises of considering more technology and other restrictions. The comprehensive method is more suitable for the industrial design of new mechanical and electrical products, which can truly achieve the human-centered design aim.

Abstract: The switched reluctance drive (SRD) is a new-type speed regulating motor drive system. It’s developed rapidly in the 1980s. The SRD is studied and designed all over the world. A simple SRD system had been designed based on the single chip microcomputer (C8051F310). The asymmetric bridge circuit is used to drive switched reluctance motor (SRM). Programming for microcomputer is based on the operation principle of SRM. Testing system could work well.

Abstract: For shortcomings and deficiencies of FFT and Wavelet Transform, Hilbert Huang Transform is used in power harmonic analysis, EMD method is applied to decompose these signals from the timescale of its characteristics to realize adaptive signal of the band, And then the characteristics of frequency and amplitude of each disturbance signal are extracted on the basis of Hilbert transform. Furthermore, the paper designed a data processing platform based on the integrated software LabVIEW and Matlab with NI PXI-1042 as the carrier. The system can analyze and process the power harmonic data in real-time with the calculation of HHT, compared with the traditional analyzer, with simple operation, processing ability, graphics output etc. Experiments have proved the stability, fast calculation capability, and high precision of the system.

Abstract: Harmonic rejection ability and reflection coefficient are the most important factors in the design of impedance matching network. However, stability of impedance matching should be taken into account in applications existing load impedance variation and component deviation due to tolerance and process variation. This paper investigates variability of Pi network impedance matching analytically. The relationships between resulting reflection coefficient with component deviation and load impedance variation are theoretically derived on the basis of Q-based design method. The deviation from perfect match due to component deviation is proportional to quality factor. Higher quality factor probably means poorer quality in terms of variability. The resulting reflection coefficient caused by load impedance variation increases rapidly when the load reflection coefficient is larger than 0.66. A small variation in the load impedance will cause a large deviation from perfect match when the impedance difference between load and source is quite large.

Abstract: Multi path routing protocol plays important part in the multi hop heterogeneous wireless sensor network. To get better performance, adaptive Wireless Senor Network Multi Path Routing Scheme (AMRH) is proposed, which is made up of three phrases: initial setup, route discovery and establishment, route maintenance. In the first phrase, every node gets the initial route table. In the second phrase, source node will find minimum-cost path among multiple paths. In the third phrase, route maintenance is conducted under adaptive mechanism. Simulation shows that AMRH scheme can prolong sensor network lifetime by 19.5%, increase data delivery ratio by 5.6%.

Abstract: This paper mainly studies the integrated navigation system technology of GPS and microelectronic mechanical system (MEMS) concerning on embedded processor S3C2440A. The system has the advantages of low cost, fast speed and small size, etc., which give wide prospects in a personal navigation application. This paper introduces the system hardware circuit structure design, emphasize on GPS navigation, MEMS inertial device for auxiliary navigation system software algorithm, and use Matlab to do data simulation on system model. The results show that GPS/MEMS inertial component integrated navigation obviously improved relative to separate GPS navigation or Strapdown inertial navigation in the accuracy and application value.

Abstract: This paper introduces the capacitor bank equipped with overvoltage protection and overcurrent protection. Then with a group of capacitor for reactive power compensation as the research object, this paper analyses the influence of harmonic to the two protection modes when the electromagnetic, static or microcomputer relay are applied.

Abstract: According to the three-phase squirrel-cage asynchronous motor rotor broken bar fault, presented with parameters identification method of asynchronous motor parameter identification to monitoring and diagnosis of rotor resistance variation of rotor bar breaking principle. Choose a three-phase squirrel-cage asynchronous motor in three working points of experiments, results show that the method is correct and feasible. This method is based on the three-phase squirrel-cage asynchronous motor steady state model parameter equation, using the method of least squares identification parameters, and consider the effects of temperature on the parameters, by the parameter variation in diagnosis of broken rotor bar fault. Advantages of simple scientific method, this method can also be used in conjunction with other methods and, on the three-phase squirrel-cage asynchronous motor rotor has no fault diagnosis.

Abstract: A bi-directional inverter for AC bus wind-solar-diesel hybrid generation system is studied in this paper. Topology of power circuit is optimized. And novel current decoupling deadbeat control strategy is adopted in current loop to improve dynamic performances. Small capacity prototype is implemented based on dsPIC30F3011.The experimental results show that the bi-directional inverter has unity power factor and can realize bi-directional power flowing.