High-efficiency switch-linear-hybrid space solar array simulator with a simple thermal design method for linear power stage

Switching power supply is an important field of application of power electronic technology, the high frequency switching DC power supply with high efficiency, small size, light weight and other advantages obtain the widespread application. The application of synchronous rectifier technology, photoelectric coupling isolation technology and the active clamp forward converter design high frequency switching power supply with 16~40V DC input and 5V/100W DC output . its operational principle is analyzed, and using LM5026 control chip describes design method of switching power supply.

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Development of a New Design Method for High Efficiency Swept Low Pressure Axial Fans With Small Hub/Tip Ratio

Volume 1A: Aircraft Engine; Fans and Blowers ◽

10.1115/gt2014-25932 ◽

2014 ◽

Cited By ~ 1

Author(s):

Thore Bastian Lindemann ◽

Jens Friedrichs ◽

Udo Stark

Keyword(s):

High Efficiency ◽

Design Method ◽

Tangential Velocity ◽

Pressure Rise ◽

Low Pressure ◽

Aerodynamic Performance ◽

Low Noise ◽

Angle Distribution ◽

Sweep Angle ◽

Reduced Pressure

For a competitive low pressure axial fan design low noise emission is as important as high efficiency. In this paper a new design method for low pressure fans with a small hub to tip ratio including blade sweep is introduced and discussed based on experimental investigations. Basis is an empirical axial and tangential velocity distribution at the rotor outlet combined with a distinctive sweep angle distribution along the stacking line. Several fans were designed, built and tested in order to analyze the aerodynamic as well as the aeroacoustic behavior. For the aerodynamic performance particular attention was paid to compensate the influence of reduced pressure rise and efficiency due to increasing blade sweep. This was achieved by a method of increasing the blade chord depending on the local sweep angle which is based on single airfoil data. The tested fans without this compensation revealed a significant noise reduction effect of up to approx. 6 dB(A) for a tip sweep angle of 64° which was accompanied by an unsatisfactory effect of reduced overall aerodynamic performance. The second group of fans did not only confirm the method of the aerodynamic compensation by a nearly unchanged pressure rise and efficiency characteristic but also revealed an increased aeroacoustic benefit of in average 9.5 dB(A) compared to the unswept version. Beside the overall characteristics the individual differences between the designs are also discussed using results of wall pressure measurements which show some significant changes of the blade tip flow structure.

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NUMERICAL THERMAL MODEL OF AN INCANDESCENT LAMP FOR SATELLITES TESTING

10.15593/2224-9982/2020.61.06 ◽

2020 ◽

pp. 50-58

Author(s):

Dmitriy Kulikov ◽

Keyword(s):

Mathematical Modeling ◽

Thermal Model ◽

High Efficiency ◽

Complex Problem ◽

Thermal Design ◽

Halogen Lamp ◽

Quality Model ◽

Good Convergence ◽

The Monte Carlo Method ◽

Model Generator

In the present article the author gives the results work to create a numerical thermal model of infrared (IR) emitter on the base of tubular halogen lamp (THL) KGT-220-1300, as one of the elements of the equipment used when conducting thermal vacuum tests (TVT) of satellites. As a tool to solve complex problem of heat transfer used software Thermal Model Generator. Variants of calculations for the operation of the lamp at different voltages are carried out. The results of mathematical modeling using band approximation of the properties of the system elements in combination with the Monte Carlo method in solving the problem of heat exchange by radiation showed high efficiency. The performed analysis of the correctness of the results showed good convergence with the data of previous experiments on measuring the temperature of the quartz bulb, which confirms the reliability of the results. Getting a high-quality model of this type at the disposal of satellite thermal engineer is an important step in the complex work aimed at conducting end-to-end mathematical modeling of satellite thermal design, and will also solve a number of issues related to the methodological support of TVT, their implementation and optimization.

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High-efficiency antenna-to-antenna polarization converters for customized polarization angle deflection

International Journal of Microwave and Wireless Technologies ◽

10.1017/s175907872000001x ◽

2020 ◽

Vol 12 (7) ◽

pp. 688-694

Author(s):

Manlan Deng

Keyword(s):

High Efficiency ◽

Design Method ◽

Ring Resonators ◽

Polarization Angle ◽

Dipole Antennas ◽

Transmitted Waves ◽

Angle Rotation ◽

Transmitting Antenna ◽

Antenna Polarization ◽

Polarization Converters

AbstractIn this paper, an antenna-to-antenna method to design high-efficiency polarization converters was proposed. Two in-linked split ring resonators (SRRs) were used as the fundamental unit cell, which can effectively make the original linear polarization angle deflected into a customized one (include but not limited to 90°). The same as the process of energy reception and transmitting of microstrip symmetric dipole antennas, the top SRR plays the role of a receiving antenna and the bottom one acts as a transmitting antenna. Under normal illumination, the strong coupling between electric resonance and magnetic resonance can result in high transmission and broad bandwidth. Since the two SRRs act as two independently polarization selective components, the polarization angle of transmitted waves can be easily controlled by rotating the transmitting SRRs around the center. The proposed concept and the design method are validated using numerical simulations, as well as experimental results of three examples for 45, 60 and 90° polarization angle rotation, the polarization conversion ratio of which is about 92.2, 88.9 and 91.9% from 7.5 to 10 GHz.

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Optimization thermal design method for space cameras based on thermo-optical analysis and Taguchi method

Optical Engineering ◽

10.1117/1.oe.59.7.075101 ◽

2020 ◽

Vol 59 (07) ◽

pp. 1 ◽

Cited By ~ 1

Author(s):

Gaopeng Zhang ◽

Hong Zhao ◽

Yaohong Chen ◽

Guangdong Zhang ◽

Zhi Zhang ◽

...

Keyword(s):

Taguchi Method ◽

Design Method ◽

Thermal Design ◽

Optical Analysis

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Topology optimization of induction heating model using sequential linear programming based on move limit with adaptive relaxation

Open Physics ◽

10.1515/phys-2017-0100 ◽

2017 ◽

Vol 15 (1) ◽

pp. 845-850 ◽

Cited By ~ 3

Author(s):

Hiroshi Masuda ◽

Yutaro Kanda ◽

Yoshifumi Okamoto ◽

Kazuki Hirono ◽

Reona Hoshino ◽

...

Keyword(s):

Linear Programming ◽

Topology Optimization ◽

Induction Heating ◽

High Efficiency ◽

Magnetic Energy ◽

Design Method ◽

Point Of View ◽

Sequential Linear Programming ◽

Electrical Machinery ◽

Heating Model

AbstractIt is very important to design electrical machineries with high efficiency from the point of view of saving energy. Therefore, topology optimization (TO) is occasionally used as a design method for improving the performance of electrical machinery under the reasonable constraints. Because TO can achieve a design with much higher degree of freedom in terms of structure, there is a possibility for deriving the novel structure which would be quite different from the conventional structure. In this paper, topology optimization using sequential linear programming using move limit based on adaptive relaxation is applied to two models. The magnetic shielding, in which there are many local minima, is firstly employed as firstly benchmarking for the performance evaluation among several mathematical programming methods. Secondly, induction heating model is defined in 2-D axisymmetric field. In this model, the magnetic energy stored in the magnetic body is maximized under the constraint on the volume of magnetic body. Furthermore, the influence of the location of the design domain on the solutions is investigated.

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Improved adaptive input voltage control of a solar array interfacing current mode controlled boost power stage

Energy Conversion and Management ◽

10.1016/j.enconman.2015.03.100 ◽

2015 ◽

Vol 98 ◽

pp. 369-375 ◽

Cited By ~ 15

Author(s):

Moshe Sitbon ◽

Shmuel Schacham ◽

Teuvo Suntio ◽

Alon Kuperman

Keyword(s):

Voltage Control ◽

Current Mode ◽

Input Voltage ◽

Solar Array ◽

Power Stage

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Some Issues of BIM Application in Landscape Architecture

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.368-370.92 ◽

2013 ◽

Vol 368-370 ◽

pp. 92-98 ◽

Cited By ~ 1

Author(s):

Sheng Lu ◽

Fang Wang

Keyword(s):

Construction Industry ◽

Landscape Architecture ◽

High Efficiency ◽

Design Method ◽

Digital Age ◽

Landscape Design ◽

Digital Resource

With Chinese construction industry into the digital age. BIM became mainstream of design method with its advantages of high efficiency, wholeness and visualization. Landscape Architecture must be aware that BIM application is necessary to development in landscape design, especially Landscape Architecture as a new first level discipline since 2011 in China. On the basis of issues that BIM application encountered in the Chinese construction industry, this paper discuss important issues of BIM application that Landscape Architecture must to be solved firstly, namely the awareness of BIM, BIM standard for Landscape Architecture, software and digital resource.

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