Advanced Materials Research Vols. 986-987

Abstract: This paper is about how to design an improved anti-ribboning method for the winder system. The system is based on the principle of a brushless DC motor control, which constantly changes relative velocity between the grooved drum and the yarn bobbin. This in turn, causes the changing of the winding ratio value. Therefore, it will accomplish the anti-ribboning control. Compared with the traditional anti-ribboning methods, the improved method can save more mechanical components and maintenance costs. Also, this method can develop different programs for different yarns. Therefore, this method is more efficient and versatile.

Abstract: High-frequency electronic circuit is an important basic specialized course for the major of electronic information engineering, communication engineering, and electronic science and technology. Combined with a dozen years of classroom teaching experience and started from several aspects like relevancy of front-back courses, teaching framework and theoretical teaching content, this paper will discuss analogy teaching method of related content about signal amplifier, mixing, modulation and demodulation in order to help students to understand chapter structure. In the process of teaching, we should pay more attention to students ' weaknesses of knowledge, then stimulate their interests in learning and improve the teaching effectively quality.

Abstract: The establishment of an accurate battery model is crucial to the design and research of battery and battery management system. This paper takes 180Ah LiFePO4 as research object, adopts PNGV model to describe the working characteristics of the battery,establishes PNGV simulation model in MATLAB/Simulink, recognizes the model parameters based on the experiment of HPPC pulse, verifies the accuracy of model in different conditions. The results show that PNGV model can show the dynamic characteristic of battery well.

Abstract: Auxiliary power of Three-phase photovoltaic inverter is supplied by solar cells with wide input ranging from 140V to 1000V.The conventional single-switch flyback converter exists too high voltage stress in power switch to be applied in this inverter. This paper presents a dual-switch flyback converter in which the voltage stress of each switch is slightly higher than the input voltage when switches turn off, at the same time , the leakage inductance energy is recycled back into the inputside; otherwise, this topology needs no snubber circuit, so it is much more efficient than single switch flyback. The dual switch flyback converter with seven outputs is successfully applied in 10KW three phase PV inverter.

Abstract: Spatial chirp will cause temporal width broadening and wave front aberration with the femtosecond pulse beam. So effectively controlling and utilizing the spatial chirp has great significance. In this manuscript, the properties of the spatial chirp are theoretically investigated. An experimental setup which can easily control the spatial chirp of the femtosecond laser pulse beam and generate vortex femtosecond pulse beam with different spatial chirp parameters is proposed. The relationships between the spatial chirp and the temporal and spatial properties including the cross section intensity distributions and the temporal width and chirp of the femtosecond pulse beams are obtained. Both theoretical and experimental results indicate that as the spatial chirp parameter becomes larger, both the temporal and spatial pulse beam widths are broadening and the wave front aberration also becomes larger quickly. Moreover, the temporal chirp is also becoming larger when the spatial chirp parameter becomes larger. The spatial chirp properties of vortex and Gaussian femtosecond pulse beams are similar with each other.

Abstract: The leakage magnetic field and equivalent circuit model of OLTC double-winding power transformer has been established by electromagnetic field Finite Element analysis software. The method of field-circuit coupled method has been used to calculate its magnetic field leakage, the short circuit impedance obtained by the calculation of formula and compared with the experimental data. At the same time, based on the calculation method for the Visual Basic language as a tool for MAGNET software for secondary development, obtain the software to calculate the short-circuit impedance of power transformer simulation software, and is verified by using the typical products, proves the validity of this software.

Abstract: The amorphous core dry-type transformer is a new energy-saving transformer. In this paper, a SCBH15-600/10 type amorphous core dry-type transformer is analyzed by 3-D finite element calculation of iron core and winding thermal. Analyzing the temperature distribution characteristics of amorphous transformer, assure the temperature rise highest point. It is in the permitted error between the simulation value and test value. It has important engineering value for the calculation of similar transformer temperature rise; and has certain guiding significance on the amorphous transformer structure design.

Abstract: According to the technical requirement of biogas power generation system, introducing the working principle of electronic igniter which is controlled by MCU; Designing and developing the electronic igniter which used STC 89 C-52 RC MCU as the core;Having completed the hardware circuit designs of power supply module, main control module and ignition module of electronic igniter. After testing the signal of circuit, it meets the technical requirements of biogas power generation system.

Abstract: Analyze the necessity of the standard management of explosive in the blasting equipment library of the coal mine, use digital monitoring technology, communications technology, software technology and sensor technology, use high-performance MCU STC12C5A60S2 and according to the instructions, control the opening and closing of the electronic lock, providing intelligent management

Abstract: A microstrip leaky wave antenna with operating frequency 2.5GHz is designed based on composite right/left handed transmission line. The beam scanning of the antenna can be controlled by changing the bias voltage of varactor in the antenna. And the performance, S-parameters and horizontal polarization pattern, of the antenna are investigated by simulation and experimental measurement, respectively. The results show that the designed antenna has better beam scanning, which is proper to be used in wireless local area networks and short-range wireless technology.