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双联齿轮泵三速控制回路的分析与设计
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作者 胡燕平 齐涤非 《煤炭技术》 CAS 1997年第2期16-17,31,共3页
齿轮泵结构简单、价格便宜、抗污染能力较强,在煤矿机械和工程机械中广泛使用.但齿轮泵是定量泵,如果要调节油缸或马达的速度,则只能采用节流调速.节流调速系统容积效率低,油液温升高,影响液压件的使用寿命.有些齿轮泵液压系统采用双泵... 齿轮泵结构简单、价格便宜、抗污染能力较强,在煤矿机械和工程机械中广泛使用.但齿轮泵是定量泵,如果要调节油缸或马达的速度,则只能采用节流调速.节流调速系统容积效率低,油液温升高,影响液压件的使用寿命.有些齿轮泵液压系统采用双泵快慢速控制,如图1所示.图1中1为低压大流量泵;2为高压小流量泵;3为安全阀,起安全保护作用;4为低压溢流阀;5、6是单向阀.当系统工作在空载快速工况时,系统工作压力低,安全阀3和溢流阀4都是关闭的.此时泵1和泵2分别通过单向阀6和5向系统供油,实现快速运动.当系统在工作状态时,系统压力升高,低压溢流阀4打开,大流量泵1卸荷,单向阀6关闭,系统只由小泵2供油作慢速运动. 展开更多
关键词 齿轮泵 双联齿轮泵 回路 三速控制
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Trigonometric Regularization and Continuation Method Based Time-Optimal Control of Hypersonic Vehicles
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作者 LIN Yujie HAN Yanhua 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第S01期52-59,共8页
Aiming at the time-optimal control problem of hypersonic vehicles(HSV)in ascending stage,a trigonometric regularization method(TRM)is introduced based on the indirect method of optimal control.This method avoids analy... Aiming at the time-optimal control problem of hypersonic vehicles(HSV)in ascending stage,a trigonometric regularization method(TRM)is introduced based on the indirect method of optimal control.This method avoids analyzing the switching function and distinguishing between singular control and bang-bang control,where the singular control problem is more complicated.While in bang-bang control,the costate variables are unsmooth due to the control jumping,resulting in difficulty in solving the two-point boundary value problem(TPBVP)induced by the indirect method.Aiming at the easy divergence when solving the TPBVP,the continuation method is introduced.This method uses the solution of the simplified problem as the initial value of the iteration.Then through solving a series of TPBVP,it approximates to the solution of the original complex problem.The calculation results show that through the above two methods,the time-optimal control problem of HSV in ascending stage under the complex model can be solved conveniently. 展开更多
关键词 hypersonic vehicle(HSV) optimal control trigonometric regularization method(TRM) continuation method
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立式脱溶干燥机在醇法大豆浓缩蛋白加工中的应用 被引量:1
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作者 曹瑞军 郑圣军 申燕 《中国油脂》 CAS CSCD 北大核心 2014年第9期80-82,共3页
为了提高和完善醇法大豆浓缩蛋白的脱溶和烘干工艺,我公司研制了新型立式脱溶干燥机。介绍了立式脱溶干燥机的结构和工作原理,并对其中所用到的关键技术和参数进行了说明。实践证明,该设备具有性能稳定、操作维修简单、干燥效率高、产... 为了提高和完善醇法大豆浓缩蛋白的脱溶和烘干工艺,我公司研制了新型立式脱溶干燥机。介绍了立式脱溶干燥机的结构和工作原理,并对其中所用到的关键技术和参数进行了说明。实践证明,该设备具有性能稳定、操作维修简单、干燥效率高、产品指标好等优点,非常适用于醇法大豆浓缩蛋白的脱溶干燥。 展开更多
关键词 大豆浓缩蛋白 立式脱溶干燥机 无缝管拉撑 加热圆盘平面度 锥形转子 三速控制
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嵌入式液晶温控器
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《电气应用》 北大核心 2008年第3期93-93,共1页
(1)适用于风机盘管及单压缩机制冷。 (2)盘管风机可实现手动及自动三速控制。 (3)墙面暗装方式带来美观的外形和超大液晶显示。
关键词 嵌入式液晶温控器 三速控制 节能 红外遥控功能
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Three-dimensional nonlinear coupling guidance for hypersonic vehicle in dive phase 被引量:3
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作者 ZHU JianWen LIU LuHua +1 位作者 TANG GuoJian BAO WeiMin 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第9期1824-1833,共10页
Three-dimensional(3D)nonlinear diving guidance strategy considering the coupling between longitudinal and lateral motions for hypersonic vehicle is investigated in this paper.It constructs the complete nonlinear coupl... Three-dimensional(3D)nonlinear diving guidance strategy considering the coupling between longitudinal and lateral motions for hypersonic vehicle is investigated in this paper.It constructs the complete nonlinear coupling motion equation without any approximations based on diving relative motion relationship directly,and converts it into linear state space equation with the same relative degree by feedback linearization.With the linear equation,slide mode control with strong robustness is employed to design the guidance law,and 3D diving guidance law which can satisfy terminal impact point and falling angle constraints with high precision is obtained by substituting the previous control law into the origin nonlinear guidance system.Besides,regarding lateral overload as the standard,hybrid control strategy which can take full advantage of the excellent characters of both bank-to-turn(BTT)and skid-to-turn(STT)controls is designed to improve the guidance accuracy further.Finally,the results of CAV-H vehicle guidance test show that the algorithm can realize high accuracy guidance even if serious motion coupling exists,and has strong robustness to the path disturbances and navigation errors as well. 展开更多
关键词 hypersonic vehicle 3D diving guidance COUPLING feedback linearization slide mode control hybrid control strategy
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