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Chinese Journal of Aeronautics 2024年第10期37卷 435-444页

作者： Qi ZHONG Junxian WANG enguang xu Cheng YU Yanbiao LI College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023China Key Laboratory of Special Purpose Equipment and Advanced Processing Technology Ministry of Education and Zhejiang ProvinceZhejiang University of TechnologyHangzhou 310023China

Hydraulic circuits with high speed on/off valve(HSV)for servo control have become commonplace in ***,the individual valve that is not volume-optimized results in a large total size of hydraulic control system,diminishing the *** address this issue,the high-precision equivalent reluctance model of the HSV is established by employing an equivalent magnetic circuit,on which the dynamic characteristic of the HSV,as well as the effects of structural parameters on switching behaviour,are *** on this model,multi-objective optimization is adopted to design an HSV with faster dynamic performance and smaller volume,NSGA-II genetic algorithm is applied to obtain the Pareto front of the desired *** assess the impact before and after optimization,an HSV based on the optimized structure is manufactured and *** experimental results show that the optimized HSV reduces 47.1%of its solenoid volume while improving opening and closing dynamic performance by 14.8%and 43.0%respectively,increasing maximum switching frequency by 6.2%,and expanding flow linear control area by 6.7%.These results validate the optimized structure and indicate that the optimization method provided in the paper is beneficial for developing superior HSV.

关键词： High speed on/off valve Dynamic response Volume Multiobjective optimization NSGA-II genetic algorithm

Switching Frequency Improvement of a High Speed on/off Valve Based on Pre-excitation Control Algorithm

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Chinese Journal of Mechanical Engineering 2024年第4期37卷 94-106页

作者： Qi Zhong Xiaotian Li Yongxin Mao enguang xu Tiwei Jia Yanbiao Li Huayong Yang College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China Key Laboratory of Special Purpose Equipment and Advanced Processing Technology Ministry of Education and Zhejiang ProvinceZhejiang University of TechnologyHangzhou 310023China

The high-speed on/off valve(HSV)serves as the fundamental component responsible for generating discrete fluids within digital hydraulic *** the switching frequency of the HSV increases,the properties of the generated discrete fluid approach those of continuous ***,a higher frequency response characteristic of HSV is the key to ensure the control accuracy of digital hydraulic ***,the current research mainly focuses on its dynamic performance,but neglect its *** paper presents a theoretical analysis demonstrating that the FRC of the HSV can be enhanced by minimizing its switching *** maximum switching frequency(MSF)is mainly determined by opening dynamic performance when HSV operates with low switching duty ratio(SDR),whereas the closing dynamic performance limits the MSF when HSV operates with high *** upon these findings,the pre-excitation control algorithm(PECA)is proposed to reduce the switching time of the HSV,and consequently enhance its *** results demonstrate that PECA shortens the opening delay time of HSV by 1.12 ms,the closing delay time by 2.54 ms,and the closing moving time by 0.47 ms in comparison to the existing advanced control *** a result,a larger MSF of 417 Hz and a wider controllable SDR range from 20%to 70%were achieved at a switching frequency of 250 ***,the proposed PFCA in this paper has been verified as an effective and promising approach for enhancing the control performance of digital hydraulic systems.

关键词： High speed on/off valve Switching frequency Pre-excitation Dynamic performance Switching duty ratio

Dynamic performance and temperature rising characteristic of a high-speed on/off valve based on pre-excitation control algorithm

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Chinese Journal of Aeronautics 2023年第10期36卷 445-458页

作者： Qi ZHONG enguang xu Geng XIE Xiele WANG Yanbiao LI College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023China Key Laboratory of Special Purpose Equipment and Advanced Processing Technology Ministry of Education and Zhejiang ProvinceZhejiang University of TechnologyHangzhou 310023China

High speed on/off valve(HSV)is an essential component in aerospace digital hydraulic systems(ADHS).Dynamic performance and temperature rising characteristic are two important features,which determine the performance of HSV,and affect the response speed and reliability of *** the driving voltage is an effective method for improving the dynamic performance of ***,continuous high voltage excitation will lead to more wasted energy,higher temperature rising and lower *** solve this problem,a pre-excitation control algorithm(PECA)is proposed in this paper based on the theoretical model of the influence of electrical parameters on dynamic performance and temperature rising *** PECA,an appropriate initial coil current is generated by pre-excitation instead of increasing driving voltage,which significantly shortens the switching delay ***,based on real-time current online calculation and feedback mechanism,the adaptive switching of five equivalent voltages is ***,the coil current can be rapidly kept at the expected state without consuming more energy and generating more *** indicate that compared with conventional PWM control algorithm,the PECA can improve dynamic performance of HSV,shorten the total switching time by 71.5%,and increase the maximum operation ***,the linear area of flow characteristic is expended by 80.0%,the adjusting time of HSV-controlled system is reduced by 23%,while shortening steady error by 46.7%.Moreover,the temperature rising characteristics of HSV are better,the maximum operation temperature is reduced by 68.6%,and the time to reach the steady state temperature is shortened by 20%.From the results,it can be concluded that the PECA is not only an effective and practical control algorithm for improving the performance of HSVs and HSV-controlled systems while reducing the heat generation and decreasing the temperature rising of HSV,but also can be a potentia

关键词： High speed on/off valve Dynamic performance Pre-excitation Temperature rising Flow characteristic

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热处理工艺对铜电缆组织及性能的影响

热加工工艺 2024年第5期53卷 77-83页

作者：陈威祝平徐恩光汪勇陈静徐静陈兴武李华强陕西科技大学机电工程学院陕西西安710021 中国船舶集团有限公司第十二研究所陕西兴平713102 远东电缆有限公司江苏宜兴214200 西安交通大学电气绝缘与电力设备国家重点实验室陕西西安710049

针对当前新能源汽车充电电缆中铜导线强度与导电率难以兼顾的难题,采用不同工艺对常用充电电缆的铜线导体(φ0.8 mm)进行再结晶退火处理,旨在优化其力学性能与电学性能。结果表明:拉拔态铜线具有较高的强度(抗拉强度R_(m)=385 MPa),较... 详细信息

针对当前新能源汽车充电电缆中铜导线强度与导电率难以兼顾的难题,采用不同工艺对常用充电电缆的铜线导体(φ0.8 mm)进行再结晶退火处理,旨在优化其力学性能与电学性能。结果表明:拉拔态铜线具有较高的强度(抗拉强度R_(m)=385 MPa),较低的电学性能(导电率σ=99.4%IACS),以及较低的弯折性能(136次)。对拉拔态铜线进行不同温度(180、200、220、550、800℃)及保温时间(30 min、18 s、8 s)退火并测量样品的力学性能和导电率,发现在200℃×30 min退火后样品具有较好的综合性能,导电率增大至103.3%IACS,弯折性能增大至318次。再结晶退火使铜线内部的微观结构发生明显变化,性能的变化与微观组织的变化息息相关。

关键词：新能源充电电缆退火微观结构力学性能电学性能

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低碳经济模式下腐植酸类农药的作用

腐植酸 2010年第5期 1-4,28页

作者：许恩光黑龙江省林科院哈尔滨150081

低碳经济模式下,腐植酸类农药作用是多方面的,包括碳同化、节能减排和环境保护等杰出的表现,腐植酸类农药在生态农业、有机农业和农药多功能化方面的作用,已远远超出农药的范畴,在未来农药的发展中具有广阔前景。

关键词：腐植酸类农药低碳经济模式节能减排有机农业多功能

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腐植酸类农药的发展前景

腐植酸 2007年第4期 6-10页

作者：许恩光黑龙江省林业科学院哈尔滨150040

介绍了腐植酸作为农药、农药的载体、农药的增效剂所具有的功能和作用,以及腐植酸作为一种天然化合物在未来农业持续发展中的环保作用。

关键词：腐植酸农药农业持续发展

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腐植酸的活性探讨

腐植酸 2013年第3期 1-5页

作者：许恩光黑龙江省林业科学院哈尔滨150081

腐植酸是有活性的有机质,其活性是连结大农业、大工业、大医药、大环境的纽带,抓住这个纽带就能更深入了解腐植酸的多功能,更好地利用它为低碳经济服务。探讨有活性的有机质形成,可以促使我们在开发腐植酸各种产品上注入新的思维,不断创... 详细信息

腐植酸是有活性的有机质,其活性是连结大农业、大工业、大医药、大环境的纽带,抓住这个纽带就能更深入了解腐植酸的多功能,更好地利用它为低碳经济服务。探讨有活性的有机质形成,可以促使我们在开发腐植酸各种产品上注入新的思维,不断创新,开拓腐植酸发展的新局面。

关键词：腐植酸活性有机质低碳经济创新

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腐植酸类农药及其发展前景

腐植酸 2004年第2期 1-6,36页

作者：许恩光曾宪成黑龙江省林科院哈尔滨150040 中国腐植酸工业协会北京100011

腐植酸类农药是一种新型的绿色环保农药,具有高效、低毒、安全、环保等特点。腐植酸类农药的出现,标志着一类环保型无公害农药的开发方向。它把原农药的单向调节(即靶标生物)扩展到环境保护,将有害生物宏观调节扩大到微生态调节。腐植... 详细信息

腐植酸类农药是一种新型的绿色环保农药,具有高效、低毒、安全、环保等特点。腐植酸类农药的出现,标志着一类环保型无公害农药的开发方向。它把原农药的单向调节(即靶标生物)扩展到环境保护,将有害生物宏观调节扩大到微生态调节。腐植酸类农药还可将化学农药与生物农药联结到一起,建立一个化学农药——腐植酸类物质——生物农药三位一体的绿色环保农药支柱,为农业可持续发展提供一条新路。

关键词：腐植酸类农药无公害农药环境保护微生态调节生物农药发展前景

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滇西南地区樟科17种木材解剖特征研究

华南农业大学学报 2014年第5期35卷 102-107页

作者：孙瑾王晓静王飞徐恩光高振忠华南农业大学林学院广东广州510642

【目的】为樟科木材识别与系统分类研究提供依据。【方法】利用光学显微镜及扫描电子显微镜对木材结构进行观察。【结果和结论】观察结果表明17种樟科木材结构具有以下特征：散孔材，管孔组合主要为单管孔和短径列复管孔（2～3细胞），... 详细信息

【目的】为樟科木材识别与系统分类研究提供依据。【方法】利用光学显微镜及扫描电子显微镜对木材结构进行观察。【结果和结论】观察结果表明17种樟科木材结构具有以下特征：散孔材，管孔组合主要为单管孔和短径列复管孔（2～3细胞），偶见管孔团。导管分子仅具单穿孔或兼有单穿孔和梯状穿孔，梯状穿孔横隔数3～14个；管间纹孔式互列。木射线由单列射线和多列射线构成，单列射线稀少，多列射线宽多为2～3细胞。射线类型主要为异形Ⅱ型和异形Ⅲ型，少数异形I型。导管射线间纹孔式多为大圆形及圆肾形。轴向薄壁组织主要为环管束状、轮界状。射线细胞和轴向薄壁细胞中普遍存在油细胞或黏液细胞。根据观察结果，依据17种木材结构编制木材分类检索表。对导管分子穿孔板的研究表明，樟科木材属间和种间的进化程度不一致，琼楠属Beilschmiedia和厚壳桂属Cryp-tocarya木材在一定程度上是较为进化的属种。

关键词：樟科木材结构木材识别

杉木液化液交联苯酚-甲醛合成新型木材胶黏剂(英文)

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林业科学 2014年第1期50卷 140-148页

作者：孙瑾林锐航李晓增王晓波朱晓枫徐恩光华南农业大学林学院木材科学与工程系广州510642 广州市质量监督检测研究院广州510110

探讨一种无污染、无废弃物排放的胶黏剂合成工艺———碱性的杉木液化物与少量的苯酚、甲醛合成一种高性能的木材胶黏剂。检测胶黏剂的游离苯酚和游离甲醛、胶合板的胶合性能和甲醛释放量,并与工业用酚醛树脂进行性能比对。结果表明:杉... 详细信息

探讨一种无污染、无废弃物排放的胶黏剂合成工艺———碱性的杉木液化物与少量的苯酚、甲醛合成一种高性能的木材胶黏剂。检测胶黏剂的游离苯酚和游离甲醛、胶合板的胶合性能和甲醛释放量,并与工业用酚醛树脂进行性能比对。结果表明:杉木液化物-苯酚甲醛胶黏剂具有较低的游离苯酚和游离甲醛,其制得的胶合板具有更好的胶接性能和更低的甲醛释放量。红外分析结果表明:杉木液化物与苯酚、甲醛发生了化学反应,并生成了高聚物化学结构。DSC结果显示:杉木液化物-苯酚甲醛胶黏剂需要更高的固化温度,但不影响其实用性。

关键词：改性酚醛树脂液化胶接性能结构分析固化