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Table of Content

    25 June 2019, Volume 39 Issue 3 Previous Issue    Next Issue
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    An electric thrust vector calibrating algorithm using angular momentum
    CUI Zhen-Jiang, ZHOU Liang, HU Shao-Chun, GONG Jian-Jun
    2019, 39 (3):  1.  doi: 10.16708/j.cnki.1000-758X.2019.0014
    Abstract ( 418 )   PDF (3310KB) ( 552 )   Save
    More and more electric propulsion (EP) systems have been used on spacecraft for orbit correction. The configuration, installation and usage modes of electric thruster determine the adjustment strategy of EP. In most cases, the satellite in orbit needs calibration and adjustment of the electric thrust vector. An algorithm to calibrate and adjust the electric thrust vector of a certain type of GEO satellite using the change of angular momentum was presented, as well as an application case of this algorithm in orbit for the first time in China. The result of inorbit calibration suggests that the algorithm is correct and practical, providing a solution for the calibration and adjustment of EP on satellite.
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    Analysis and simulation of influence factors of spacebased optical space debris detection
    XING Bi-Da, XIN Tian, ZHENG Chang-Wen
    2019, 39 (3):  9.  doi: 10.16708/j.cnki.1000-758X.2019.0015
    Abstract ( 682 )   PDF (6312KB) ( 573 )   Save
    Optical methods are widely used in spacebased space debris detection, but they are vulnerable to stray light and other factors The factors which affect spacebased optical space debris detection are analyzed from the two aspects of detectors and debris based on the experimental data The factors affecting the detection effect include stray light such as sunlight, moonlight, earthatmosphere light and airglow, as well as radiation in South Atlantic Anomaly region The factors affecting the visibility of debris include earth occlusion, earth shadow and reflected sunlight At the same time, the characteristic quantities involved in the above factors and the calculation methods to avoid the effects are put forward The simulation results of a spacebased detection equipment show that the above effects may occur in both normal rendezvous and attitude maneuver modes, so that they should be fully considered in the experiment design Finally, a spacebased space debris detection mission is planned The article has certain guiding significance for the experiment design of spacebased optical detection.
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    Miniaturization design and implementation of solidstate currentlimit protection circuit for space
    NI Chun-Xiao, ZHAO Guo-Qing
    2019, 39 (3):  17.  doi: 10.16708/j.cnki.1000-758X.2019.0016
    Abstract ( 460 )   PDF (1346KB) ( 701 )   Save
    A solidstate currentlimit protection circuit with command control mode,onoff indication and currentlimit protection adjustment function is designed to replace the fuse in the space power bus for inrush current suppression and load overcurrent protection In order to meet the miniaturization design requirements of the products, the circuit adopts thick film process layout and wiring, and is manufactured by microassembly technology Through circuit simulation, layout design and application testing, the circuit performance meets the design requirements, and the product size is only 25mm×23mm×55mm, showing significant advantages in miniaturization design As an emerging solidstate power distribution protection product, it has broad application prospects in space power supply and distribution system。
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    Analysis of influence of solar radiation pressure on ground track keeping control in zero yaw attitude mode
    ZENG Guang, WU Xin-Lin, GONG Bing, LI Dong-Lin, WANG Chao
    2019, 39 (3):  23.  doi: 10.16708/j.cnki.1000-758X.2019.0017
    Abstract ( 417 )   PDF (4126KB) ( 410 )   Save
    The intrinsic "anomaly"  mechanism of the ground track drift of a satellite in orbit is analyzed and the model of solar radiation pressure accumulation effect in alongtrack direction in zero yaw attitude mode(keeping yaw angle zero in one orbit cycle) is built. Then, the model parameters are estimated using historical observation data through POD. Finally, the accuracy of the new model is verified by using the real ground track of the satellite in 2018. The results show that the accuracy of satellite ground track drift forecast is significantly improved by using the new model. It can provide technical support for developing the control strategy of ground track keeping for this kind of satellite.
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    Recent progress and prospect of hightemperature heat
    pipes technology
    LI Jin-Wang, DAI Shu-Gang
    2019, 39 (3):  30.  doi: 10.16708/j.cnki.1000-758X.2019.0018
    Abstract ( 1036 )   PDF (1715KB) ( 1732 )   Save
    Hightemperature heat pipes have a good heat transfer performance and can be used for high working temperature. They have an expansive application prospect in the field of thermal protection system of hypersonic vehicle, cooling of space reactor and utilization of solar energy, and so on. The recent progress of hightemperature heat pipes is reported,including the startup characteristic from the frozen state and heat transfer performance of hightemperature heat pipes, the experimental studies, the numerical analysis studies. The effects of the inclination angles, the working fluid parameters, the fill charge ratio, the noncondensable gas, the material, the structure and the sizes on the startup characteristic from the frozen state and heat transfer performance of hightemperature heat pipes are presented.The applications of hightemperature heat pipes for thermal management of hypersonic flight vehicles, cooling of space reactor and utilization of solar energy are summarized. The future development direction is also pointed out, such as the numerical analysis model and engineering application of hightemperature heat pipes. The future research suggestions of hightemperature heat pipes are also put forward.
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    Recent advances of multipactor suppression by surface treatment for highpower microwave components in China
    SONG Qiang-Qiang, CUI Wan-Zhao, YANG Jing, HU Tian-Cun
    2019, 39 (3):  43.  doi: 10.16708/j.cnki.1000-758X.2019.0019
    Abstract ( 648 )   PDF (4096KB) ( 549 )   Save
    The Secondary Electron Emission (SEE) from materials used in highpower RF devices in space is the main trigger and sustaining mechanism of the resonant avalanche electron discharge known as the multipactor effect. Multipactor effect is one of the key issues to limit the application of highpower microwave components in space. Starting from the mechanism of multipactor, the basic physical mechanism of two types of multipactors (singlesurface and twosurface)is briefly introduced, and then the current mainstream of multipactor suppression methods are summarized and the limitations of their respective applications in space highpower microwave components are given. Finally, focusing on the special problem of multipactor suppression in aerospace highpower microwave components, the research work on surface treatment to inhibit multipactor in the past five years is reviewed and the tendencies of multipactor suppression technology are predicted.
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    Satellite video pointtarget tracking  based on Hu correlation filter
    WU Jia-Qi, WANG Tao-Yang, YAN Jun, ZHANG Guo, JIANG Xiao-Hua, WANG Yun-Ming, BAI Qian, YUAN Chong
    2019, 39 (3):  55.  doi: 10.16708/j.cnki.1000-758X.2018.0059
    Abstract ( 487 )   PDF (4317KB) ( 728 )   Save
    Aiming at the moving object tracking problem of satellite video, a robust method of feature description and matching based pointtarget tracking is proposed. The idea of correlation filter is introduced. Firstly, Hu invariant moments and median filtering of the sample set are used to establish the tracking template of the target and describe the target features. Then, the dimension of the decision area of target tracking is reduced and the Hu confidence model of the judgment area is established. Finally, the target tracking is achieved by finding the maximum value of the tracking confidence map by using the fast FFT derivation correlation method. Moreover, the robustness of the algorithm is improved by using Kalman filtering to assist and optimize the tracking process. The experimental video data are taken from SkySat1 and Jinlin1 satellites. The tracking experiments of 5 point targets show that the proposed method achieves good results in the satellite video, and that the accuracy is better than 90%. The target is not lost in the whole tracking process and the tracking trajectory is smooth. In addition, for the 13×13 judgment area, the processing speed of the confidence map is about 5 times higher than the conventional correlation method. This method can provide a technical basis for achieving fast and reliable tracking of point targets in satellite video.
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    Numerical simulation and experimental analysis for cavitation in composite centrifugal pump
    CHAO Wen-Xiong, WANG Jun-Ru, WANG Fei, ZANG Hua-Bing, SHI Bao-Lu
    2019, 39 (3):  64.  doi: 10.16708/j.cnki.1000-758X.2019.0020
    Abstract ( 445 )   PDF (2775KB) ( 712 )   Save
    In order to study the cavitation of certain type of aerospace centrifugal pump, the multiphase model on the basis of Mixture was used together with cavitation modelThe steady constant value of vaporliquid phases was simulated under the condition of different negative pressures at inlet of water glycol inside the centrifugal pump with long and short composite impellers, and the cavitation test was conducted with different inlet pressures The results indicate that the vaporization area expands along with the increase of negative pressure In case the negative pressure at inlet is -50kPa and the pressure difference at pump inlet and outlet is 155kPa,already approaching the 3% allowance of rated pressure difference, the pressure at outlet of centrifugal pump is 105kPa which is the critical cavitation pressure at outlet In case the negative pressure at inlet is -60kPa, the flow rate at outlet suddenly changes to 300L/h, the critical cavitation state occurs to the pump, and the inlet pressure is less than 10kPa that is the minimum pressure required in technical specification Therefore, cavitation will not occur when the pump operates at its working range, and reliability of the value simulation in this paper is also verified.
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    Research and realization of model based satellite telemetry and command information flow digital design method
    YE Mian, HAN Xiao-Dong, HAO Yan-Yan, WANG Yi-Yi
    2019, 39 (3):  71.  doi: 10.16708/j.cnki.1000-758X.2019.0021
    Abstract ( 480 )   PDF (3118KB) ( 455 )   Save
    Information flow design for telemetry and command(T&C) is one of the essential parts of satellite general information design. The information flow design for telemetry and command reflects the movement of telemetries and commands. Satellite resource distribution and onboard equipment layout are determined by the rationality and validity of design result. Nowadays, traditional T&C information flow design method cannot satisfy the requirements of digital design mode and increasing assignment demand. To solve these problems, a new modelbased satellite T&C information flow digital design method is proposed by using graphic equivalent model. This method not only remedies the disadvantage of traditional design method, but also can be used in optimal design. This method has been tested by a satellite project,and test result shows that manhour is reduced by 975%. At the same time, the validity reaches 100%. It is proved that the new method can increase design efficiency, enhance designing quality, and improve standardization of T&C information flow design process, method and product. Moreover, it can promote the automatization level of information flow design.
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    Application of selfadaptive fuzzy PID technology in launch site gas supply system
    YANG Yi-Qi, LIU Hao-Yang, YUE Long-Hua, WANG Tian-Hang
    2019, 39 (3):  81.  doi: 10.16708/j.cnki.1000-758X.2019.0022
    Abstract ( 379 )   PDF (2252KB) ( 480 )   Save
    Aiming at the problems of nonlinear pressure control, large timelag and variable parameters, a closed loop pressure control system is designed based on selfadaption fuzzy PID technology. By online adjusting of the proportional coefficient Kp,the integral coefficient Ki and the differential coefficient Kd of the controller, high precision control of the pressure is realized. Based on the test data, a secondorder lag inertia model is established by curve fitting and simulation. The simulation verifies the validity of the model. The conclusion shows that this control effect is better than the conventional PID control, and can effectively improve the dynamic performance and steadystate accuracy of the system. It can be widely used in the automatic control system of the launch site where PLC control is a core method.
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