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结合机器学习的无人机自主对接过程的目标识别定位

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电讯技术 2024年第9期64卷 1379-1385页

作者：姚垚李军府胡志勇艾俊强航空工业第一飞机设计研究院西安710089

针对无人机空中自主对接时,软式锥套受尾流场和牵引力强位置约束、锥套传递力等因素导致拖曳锥套运动复杂而存在扰动、鞭打等干扰的问题,提出一种基于机器视觉的单目视觉自主实时识别与定位方法,通过特征提取与分类器分类进行目标检测... 详细信息

针对无人机空中自主对接时,软式锥套受尾流场和牵引力强位置约束、锥套传递力等因素导致拖曳锥套运动复杂而存在扰动、鞭打等干扰的问题,提出一种基于机器视觉的单目视觉自主实时识别与定位方法,通过特征提取与分类器分类进行目标检测与识别,分阶段对无人机和靶标关键点进行实时相对位置测量。在机载探测与计算平台实验进行系统应用验证,完成了机动锥套自主对接地面实验,结果表明目标检测精度可达90%,平均响应帧率可达41.322 Hz,定位误差可达厘米量级,证明了所提的软式机动锥套空中自主对接方法的有效性。

关键词：无人机自主对接目标识别机器学习

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半导体桥火工品的防静电与防射频设计

爆破器材 2024年第1期53卷 30-35页

作者：袁玉红李军福周彬黄寅生南京理工大学化学与化工学院江苏南京210094 安徽红星机电科技股份有限公司安徽合肥231135 南京军事代表局驻蚌埠地区军事代表室安徽蚌埠233000

为提高半导体桥(SCB)火工品的防静电与防射频的双防能力,将静电加固器件瞬态电压抑制(TVS)二极管和射频加固器件负温度系数(NTC)热敏电阻同时集成入SCB火工品的结构中,并研究了上述组合器件对SCB火工品发火性能和抗电磁性能的影响规律... 详细信息

为提高半导体桥(SCB)火工品的防静电与防射频的双防能力,将静电加固器件瞬态电压抑制(TVS)二极管和射频加固器件负温度系数(NTC)热敏电阻同时集成入SCB火工品的结构中,并研究了上述组合器件对SCB火工品发火性能和抗电磁性能的影响规律。结果表明:集成防护器件后,SCB火工品的安全电流从1.2 A升至1.5 A;抗静电性能满足500 pF/500Ω/25 kV条件下不发火;在22μF/16 V的电容发火条件下,集成SCB火工品的平均爆发时间较SCB火工品增加了1.77μs。因此,该组合型防护器件可以在不改变SCB发火性能的基础上有效提高SCB的抗静电和抗射频的能力。

关键词：火工品电磁防护集成半导体桥瞬态电压抑制二极管射频加固器件负温度系数热敏电阻

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一种先进超声速民机低声爆高效气动布局设计

航空学报 2024年第6期45卷 115-133页

作者：李军府陈晴王伟韩忠华谭玉婷丁玉临谢露乔建领宋科艾俊强西北工业大学航空学院西安710072 航空工业第一飞机设计研究院西安710089 西北工业大学翼型、叶栅空气动力学国家级重点实验室西安710072 西北工业大学航空学院气动与多学科优化设计研究所西安710072

低声爆高效气动布局设计是超声速民机研究的重点和关键技术之一。采用基于声爆最小化理论反设计方法、波系有益干扰后体设计方法、参数化近场超压信号的混合可信度反设计方法,提出了一种先进超声速民机低声爆气动布局,对每一步降低声爆... 详细信息

低声爆高效气动布局设计是超声速民机研究的重点和关键技术之一。采用基于声爆最小化理论反设计方法、波系有益干扰后体设计方法、参数化近场超压信号的混合可信度反设计方法,提出了一种先进超声速民机低声爆气动布局,对每一步降低声爆的效果进行了分析并研究了该布局的全声爆毯特性;采用CFD数值求解近场声爆信号并通过Burgers方程传播到远场,研究了飞行高度、飞行马赫数等参数对该气动布局地面声爆响度的影响;采用CFD数值模拟方法研究了飞行高度、马赫数等参数对该气动布局气动特性的影响。研究表明,采用基于声爆最小化理论反设计方法降低了基准气动布局的地面声爆响度约6.54 PLdB,采用波系有益干扰后体设计方法进一步使地面声爆响度降低了约0.97 PLdB,采用参数化近场超压信号的混合可信度反设计方法使气动布局地面声爆响度进一步降低了约4.04 PLdB;合理地设计飞行高度、飞行马赫数,可以有效地降低地面声爆响度;合理地选择巡航飞行高度和巡航飞行马赫数,可以有效地提高巡航效率。研究工作对超声速民机气动布局设计具有一定的工程指导价值,对超声速民机总体气动方案设计亦具有一定的工程借鉴意义。

关键词：超声速民机低声爆气动布局地面声爆响度巡航效率马赫数飞行高度机翼后掠角

Adaptive Fitting Capacity Prediction Method for lithium‑Ion Batteries

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Automotive Innovation 2022年第4期5卷 359-375页

作者： Xiao Chu Fangyu Xue Tao liu Junya Shao junfu li School of Automotive Engineering Harbin Institute of Technology2 West Wenhua RoadHuancui DistrictWeihai 264209China Guangdong Guanghua Sci-Tech Co. Ltd.Shantou 515000China School of Chemical Engineering and Chemistry Harbin Institute of TechnologyHarbin 150001China

lithium-ion batteries have become the mainstream power source for electric vehicles because of their excellent ***,lithium-ion batteries still experience aging and capacity attenuation during *** is therefore critical to accu-rately predict battery remaining capacity for increasing battery safety and prolonging battery *** paper first adopts the metabolism grey algorithm and a simplified electrochemical model to predict battery capacity under different operating *** improve the prediction performance where the capacity changes nonlinearly,a decoupling analysis of battery capacity loss is then conducted based on the simplified electrochemical ***,an adaptive fitting method is devel-oped for capacity prediction,aiming at improving the prediction accuracy at the inflection point of battery capacity *** prediction results indicate that the developed adaptive fitting method can achieve high prediction accuracy under battery capacity attenuation at different discharge stages with errors lower than 2.2%.And the battery capacity decay shows linear variation,and the proposed method effectively forecast the inflection point of battery capacity diving.

关键词： lithium-ion battery Capacity prediction Capacity diving Adaptive fitting capacity prediction

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氧化铝厂中间降温设备配置方案分析及应用

云南冶金 2024年第3期53卷 240-247页

作者：李俊福孙江波范超王超张旭云南文山铝业有限公司云南文山663000

通过换热器的换热计算,对Ⅰ、Ⅱ、Ⅲ组分解系统换热器使用情况进行了对比分析,结果表明:Ⅰ、Ⅱ系列宜选用螺旋板式换热器,其使用寿命可达3 a;Ⅲ系列宜选用立式宽流道板式,通过优化配置后分解系统换热器运行情况统计表可知,其换热量可达4... 详细信息

通过换热器的换热计算,对Ⅰ、Ⅱ、Ⅲ组分解系统换热器使用情况进行了对比分析,结果表明:Ⅰ、Ⅱ系列宜选用螺旋板式换热器,其使用寿命可达3 a;Ⅲ系列宜选用立式宽流道板式,通过优化配置后分解系统换热器运行情况统计表可知,其换热量可达4600 kW以上。

关键词：氧化铝分解槽中间降温换热器

A branch current estimation and correction method for a parallel connected battery system based on dual BP neural networks

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Green Energy and Intelligent Transportation 2022年第2期1卷 112-123页

作者： Quanqing Yu Yukun liu Shengwen Long Xin Jin junfu li Weixiang Shen School of Automotive Engineering Harbin Institute of TechnologyWeihaiShandong 264209China School of New Energy Harbin Institute of TechnologyWeihaiShandong 264209China School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyHawthornVictoria 3122Australia

In the actual use of a parallel battery pack in electric vehicles(EVs),current distribution in each branch will be different due to inconsistence characteristics of each battery *** the branch current is approximately calculated by the total current of the battery pack divided by the number of the parallel branches,there will be a large error between the calculated branch current and the real branch *** current sensors to measure each branch current is not practical because of the high *** estimation of branch currents can give a safety warning in time when the parallel batteries of EVs are seriously *** paper puts forward a method to estimate and correct branch currents based on dual back propagation(BP)neural *** the proposed method,one BP neural network is used to estimate branch currents,the other BP neural network is used to reduce the estimation error cause by current pulse ***,this paper makes discussions on the selection of the best inputs for the dual BP neural networks and the adaptability of the method for different battery capacity and resistence *** effectiveness of the proposed method is verified by multiple dynamic conditions of two cells connected in parallel.

关键词： BP neural Network Branch current estimation and correction Electric vehicles lithium-ion battery pack

新工科背景下车用动力电池建模理论课程改革探索

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汽车实用技术 2024年第14期49卷 131-136页

作者：李俊夫胡雪丽于全庆王大方张齐哈尔滨工业大学(威海)汽车工程学院山东威海264209

随着新一轮科技革命的兴起,新能源汽车及电池产业得到了迅猛发展,新能源汽车动力电池专业人才的需求持续增长。为提高从事动力电池研发和管理人员的理论创新和工程实践能力,对车用动力电池建模理论课程教学改革提出更高的要求。文章介... 详细信息

随着新一轮科技革命的兴起,新能源汽车及电池产业得到了迅猛发展,新能源汽车动力电池专业人才的需求持续增长。为提高从事动力电池研发和管理人员的理论创新和工程实践能力,对车用动力电池建模理论课程教学改革提出更高的要求。文章介绍了新工科背景下课程的教学内容和改革目标,分析了当前课程教学过程中存在的问题,在此基础上提出新工科背景下车用动力电池建模理论课程教学改革策略。通过不断探索科研创新与教学深度融合的培养模式,完善教学设计,设立多方位考核机制,优化实践教学环节,构建数字化教学库等教学改革,培养适应新时代社会需求的新能源汽车动力电池专业人才。

关键词：新工科新能源汽车动力电池课程改革

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Effect of Bimodal Quasicrystal Phase on the Dynamic Recrystallization of Mg–Zn–Gd Alloy during High-Pressure Torsion

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1128-1134页

作者： Ping li Shuangwu Xia junfu Dong liangwei Dai Zhicheng Luo Kemin Xue School of Material Science and Engineering Hefei University of TechnologyHefei230009China

The Mg–Zn–Gd alloy with quasicrystal icosahedral phase was processed by high-pressure torsion (HPT). The effect of bimodal I-phase on the dynamic recrystallization was analyzed by transmission electron microscopy. The results showed that the block I-phase can stimulate obvious particle-stimulated nucleation and dynamic recrystallization (DRX) grains were preferentially formed after HPT for 5 turns, while the granular I-phase only promoted the generation of sub-grains. The orientation relationship was determined as twofold//[1210] and fivefold//(0002)_(Mg). Moreover, after HPT for 9 turns, the DRX grains induced by block I-phase appeared to grow up and coarsened. Compared with block I-phase, the grains induced by granular I-phase presented much smaller size and distributed more homogeneous due to the strong pinning effect.

关键词： High-pressure torsion(HPT)-Quasicrystal phase Dynamic recrystallization Particle-stimulated nucleation Orientation relationship

Performance simulation method and state of health estimation for lithium-ion batteries based on aging-effect coupling model

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Green Energy and Intelligent Transportation 2023年第3期2卷 16-29页

作者： Deyu Fang Wentao Wu junfu li Weizhe Yuan Tao liu Changsong Dai Zhenbo Wang Ming Zhao School of Automotive Engineering Harbin Institute of TechnologyWeihai 264209ShandongChina School of New Energy Harbin Institute of TechnologyWeihai 264209ShandongChina Guangdong Guanghua Sci-Tech Co. Ltd.Shantou 515000GuangdongChina School of Chemical Engineering and Chemistry Harbin Institute of TechnologyHarbin 150001HeilongjiangChina School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001HeilongjiangChina Zhuhai Zhongli New Energy Sci-Tech Co. Ltd.Zhuhai 519000GuangdongChina

Accurate simulation of characteristics performance and state of health(SOH)estimation for lithium-ion batteries are critical for battery management systems(BMS)in electric *** simplified electrochemical model(SEM)can achieve accurate estimation of battery terminal voltage with less computing *** ensure the applica-bility of life-cycle usage,degradation physics need to be involved in SEM *** work conducts deep analysis on battery degradation physics and develops an aging-effect coupling model based on an existing improved single particle(ISP)***,three mechanisms of solid electrolyte interface(SEI)film growth throughout life cycle are analyzed,and an SEI film growth model of lithium-ion battery is built coupled with the ISP ***,a series of identification conditions for individual cells are designed to non-destructively determine model ***,battery aging experiment is designed to validate the battery performance simulation method and SOH estimation *** validation results under different aging rates indicate that this method can accurately es-timate characteristics performance and SOH for lithium-ion batteries during the whole life cycle.

关键词： Improved single particle model Failure physics Characteristics performance simulation State of health estimation