Applied Mechanics and Materials Vols. 380-384

Abstract: In this essay, the characteristics and components are firstly introduced, and then the computational method of azimuth angle in the place of sun is stated. Moreover, as to the control accuracy issues which appear when electric eye holder traces the position of sun, through analyzing the changing relationship between solar azimuth and battery board azimuth, in view of the size of angle of deviation between the above azimuths, we adopt two tracking control methods that is PID and Fuzzy, and we have designed PID-Fuzzy controller that regards solar azimuth as input quantity and battery board azimuth as feedback quantity. By means of MATLAB simulation experiment, we analyze the performance of the designed PID-Fuzzy controller, and the results suggest that this method not only shorten the accommodation time but also enhance the tracking accuracy of this system, which reduces the steady-state error to less than 5%, enhances effectively photoelectric conversion efficiency, and offers a kind of referential method for the control of the similar tracking system.

Abstract: A VFC technique based on CPLD is proposed, by which the problems of isolation and remote transmission emerged in high voltage sampling systems could be well solved. The working principle, circuit configuration, and hardware realization of VFC are introduced in detail, respectively in this paper. Moreover, the problems of operation principle and conversion accuracy of VFC based on CPLD are emphasized and the corresponding method of V/F transition is proposed utilizing CPLD and DSP. Due to some significant advantages, such as, high voltage in circuit isolation, high sampling precision, easy realization, and the satisfaction in remote transition requirement, the developed VFC sampling system could be widely utilized in high voltage sampling systems. Finally, some experimental results are provided to show the effectiveness of the proposed VFC technique based on CPLD.

Abstract: This paper adopts frequency conversion method to avoid same frequency interfered, and deduces the dielectric loss factor and the equivalent capacitance using the harmonic analysis. Based on this theory, a DSP+FPGA detecting platform was built. At last, utilizing capacitance and resistance to simulate as dielectric loss measurement sample, the experiment was conducted.

Abstract: Firstly, this paper introduced the target device hardware system and software development tools, the former is based on TI DM3730. Secondly, by analyzed the bootloader workflow, and compared with different bootstrap process, TI UART was selected to transplant the UBOOT to target device. The paper provided detail operation procedures and pseudo code.

Abstract: Based upon the synopsis of SOA, this paper describes the SOA framework and related content, and then puts forward the SOA process and phase task of electronic information system. Meanwhile, further works are presented. This will benefit the development of electronic information system.

Abstract: BIM has been proven to be a key technology capable of enhancing informatization and realizing management improvement in the architectural industry. This paper discusses studies on building information sharing based on BIM and VR technology and relevant applications. It means to, on the basis of the building information modeling (BIM), integrate the BIM and VR technology and develop a manageable, amendable and expandable digital building/facility delivery system, so as to set up an integrated and 3D visual building information inquiry and management platform for construction and post-delivery operation & management.

Abstract: This paper describes a phase frequency detector application using 0.18μm CMOS process. In order to cover the high frequencies of input signals, TSPC D flip-flop structure are applied. The core area of proposal phase frequency detector is 60 μm×50 μm. The simulating results show that rang of operating frequency is from 500kHz to 500MHz and the power consumption is 0.722mW under a 1.8V supply.

Abstract: Low power lighting LED has the advantages of low cost and good heat dissipation. But the current driver for this kind of LED does not have a good efficiency. In this paper a new kind of LED driver circuit was designed. By using current mirror and PWM technique, the circuit has good efficiency. By simulation with PSPICE, we can prove that the circuit has can divide current equally and has a good performance while the voltage source has some jitters.

Abstract: a novel peak current PWM/PFM dual-mode boost dc-dc regulator applying for neural signal regeneration is proposed in this paper. The converter can adaptively switch between pulse-width modulation (PWM) and pulse-frequency modulation (PFM) both with relatively high conversion efficiency. Soft-start circuit is designed to eliminate the surge current at the start up stage of the regulator, other protection modules are also contained. The paper analyzes the model and stability of the system. The operation frequency of the regulator is 1MHz. The simulation results show the efficiency of the system is relatively high in PWM mode, up to 95%, in PFM mode it also has good efficiency.

Abstract: In this paper, mainly for the problem that high voltage circuit breaker closing at the random phase can bring hard harmfulness to the power system. We design the 35kV SF6-Phase Control circuit breaker can control speed smartly, and opens or closes with phase selection, which is equipped with the magnetic actuator. In the article, the static and transient simulation analysis which includes the load force, and carried out prototype trial and test validation. At last, the results of simulation and test is given.