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Research of the Unity Theory Between Three-level Space Vector and Carrier-based PWM Modulation Strategy 被引量:28
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作者 CHEN Juan HE Yingjie WANG Xinyu LIU Jinjun 《中国电机工程学报》 EI CSCD 北大核心 2013年第9期I0010-I0010,共1页
两电平空间矢量脉宽调制(space vector pulse widthmodulation,SVPWM)与正弦脉宽调制(sinusoidal pulse widthmodulation,SPWM)存有一定的本质关系,对于三电平,在常见的8段式SVPWM序列中可以证明,SVPWM与SPWM本质上也存在某种统一... 两电平空间矢量脉宽调制(space vector pulse widthmodulation,SVPWM)与正弦脉宽调制(sinusoidal pulse widthmodulation,SPWM)存有一定的本质关系,对于三电平,在常见的8段式SVPWM序列中可以证明,SVPWM与SPWM本质上也存在某种统一。实际的SVPWM调制中,由于要考虑中点电压平衡、减少谐波等其它性能问题,一般会利用开关冗余状态得到8段以上的开关调制序列。目前的文献中还未曾有对这些情况进行统一性地验证,因此三电平SVPWM与SPWM的统一理论存在一定的不足。研究发现,可通过严格地理论推导将传统意义上的调制波分解为2个子调制波,再进行SPWM调制,可以得到与SVPWM完全吻合的序列。该文在此方法基础上深入研究了8段以上(10、12、14段)的SVPWM调制序列与SPWM的统一。经过严格地理论推导,成功实现了含任意段数的SVPWM序列与SPWM的统一。仿真结果证明了该理论的正确性。 展开更多
关键词 三电平逆变器 SVpwm 调制策略 统一理论 载波 矢量和 空间 研究人员
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Human experience-guided reinforcement learning for carrier-based aircraft support operation scheduling
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作者 Xudong Chen Yizhe Luo +5 位作者 Qihang Sun Wenxiao Guo Zhao Jin Shuo Feng Yucheng Shi Mingliang Xu 《Defence Technology(防务技术)》 2025年第12期211-224,共14页
The efficiency of carrier-based aircraft support operation scheduling critically impacts aircraft carrier operational effectiveness by determining sortie generation rates,yet faces significant challenges in complex de... The efficiency of carrier-based aircraft support operation scheduling critically impacts aircraft carrier operational effectiveness by determining sortie generation rates,yet faces significant challenges in complex deck environments characterized by resource coupling,dynamic constraints,and highdimensional state-action spaces.Traditional optimization algorithms and vanilla reinforcement learning(RL)struggle with computational inefficiency,sparse rewards,and adaptability to dynamic scenarios,while human expert systems are constrained by the quality of expert knowledge,and poor expert guidance may even have a negative impact.To address these limitations,this paper proposes a human experience-guided actor-critic reinforcement learning framework that synergizes domain expertise with adaptive learning.First,a dynamic Markov decision process(MDP)model is developed to rigorously simulate carrier deck operations,explicitly encoding constraints on positions,resources,and collision avoidance.Building upon this foundation,a human experience database is constructed to enable real-time pattern-matching-based intervention during agent-environment interactions,dynamically correcting wrong actions to avoid catastrophic states while refining exploration efficiency.Finally,the policy and value network objectives are reshaped to incorporate human intent through hybrid reward functions and adaptive guidance weighting,ensuring balanced integration of expert knowledge with RL's exploration capabilities.Extensive simulations across three scenarios demonstrate superior performance compared to state-of-the-art methods and maintain robustness under suboptimal human guidance.These results validate the framework's ability to harmonize human expertise with adaptive learning,offering a practical solution for real-world carriers. 展开更多
关键词 Reinforcement learning from human feedback carrier-based aircraft scheduling Resource allocation Dynamic decision-making
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Recognition of carrier-based aircraft flight deck operations based on dynamic graph
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作者 Xingyu GUO Jiaxin LI +3 位作者 Hua WANG Junnan LIU Yafei LI Mingliang XU 《Chinese Journal of Aeronautics》 2025年第3期474-490,共17页
Accurate recognition of flight deck operations for carrier-based aircraft, based on operation trajectories, is critical for optimizing carrier-based aircraft performance. This recognition involves understanding short-... Accurate recognition of flight deck operations for carrier-based aircraft, based on operation trajectories, is critical for optimizing carrier-based aircraft performance. This recognition involves understanding short-term and long-term spatial collaborative relationships among support agents and positions from long spatial–temporal trajectories. While the existing methods excel at recognizing collaborative behaviors from short trajectories, they often struggle with long spatial–temporal trajectories. To address this challenge, this paper introduces a dynamic graph method to enhance flight deck operation recognition. First, spatial–temporal collaborative relationships are modeled as a dynamic graph. Second, a discretized and compressed method is proposed to assign values to the states of this dynamic graph. To extract features that represent diverse collaborative relationships among agents and account for the duration of these relationships, a biased random walk is then conducted. Subsequently, the Swin Transformer is employed to comprehend spatial–temporal collaborative relationships, and a fully connected layer is applied to deck operation recognition. Finally, to address the scarcity of real datasets, a simulation pipeline is introduced to generate deck operations in virtual flight deck scenarios. Experimental results on the simulation dataset demonstrate the superior performance of the proposed method. 展开更多
关键词 carrier-based aircraft Flight deck operation Operation recognition Long spatial-temporal trajectories Dynamic graph Biased random walk Graph embeddings
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Multi-agent Based Hierarchy Simulation Models of Carrier-based Aircraft Catapult Launch 被引量:19
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作者 王维军 屈香菊 郭林亮 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第3期223-231,共9页
With the aid of multi-agent based modeling approach to complex systems, the hierarchy simulation models of carrier-based aircraft catapult launch are developed. Ocean, carrier, aircraft, and atmosphere are treated as ... With the aid of multi-agent based modeling approach to complex systems, the hierarchy simulation models of carrier-based aircraft catapult launch are developed. Ocean, carrier, aircraft, and atmosphere are treated as aggregation agents, the detailed components like catapult, landing gears, and disturbances are considered as meta-agents, which belong to their aggregation agent. Thus, the model with two layers is formed i.e. the aggregation agent layer and the meta-agent layer. The information communication among all agents is described. The meta-agents within one aggregation agent communicate with each other directly by information sharing, but the meta-agents, which belong to different aggregation agents exchange their information through the aggregation layer first, and then perceive it from the sharing environment, that is the aggregation agent. Thus, not only the hierarchy model is built, but also the environment perceived by each agent is specified. Meanwhile, the problem of balancing the independency of agent and the resource consumption brought by real-time communication within multi-agent system (MAS) is resolved. Each agent involved in carrier-based aircraft catapult launch is depicted, with considering the interaction within disturbed atmospheric environment and multiple motion bodies including carrier, aircraft, and landing gears. The models of reactive agents among them are derived based on tensors, and the perceived messages and inner frameworks of each agent are characterized. Finally, some results of a simulation instance are given. The simulation and modeling of dynamic system based on multi-agent system is of benefit to express physical concepts and logical hierarchy clearly and precisely. The system model can easily draw in kinds of other agents to achieve a precise simulation of more complex system. This modeling technique makes the complex integral dynamic equations of multibodies decompose into parallel operations of single agent, and it is convenient to expand, maintain, and reuse the program codes. 展开更多
关键词 multi-agent system (MAS) multi-agent based modeling (MABM) TENSOR carrier-based aircraft catapult launch hierarchy simulation model
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基于DITC的开关磁阻电机软斩波PWM控制
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作者 蔡燕 刘慧 《天津工业大学学报》 北大核心 2025年第6期55-63,共9页
针对传统直接瞬时转矩控制(DITC)在每个采样周期下只施加给电机绕组固定的电压,不能根据转矩误差的大小及时调整电机绕组两端电压而造成转矩脉动大的问题,提出了一种软斩波PWM控制与双滞环DITC控制相结合的控制方法。根据转矩误差的大... 针对传统直接瞬时转矩控制(DITC)在每个采样周期下只施加给电机绕组固定的电压,不能根据转矩误差的大小及时调整电机绕组两端电压而造成转矩脉动大的问题,提出了一种软斩波PWM控制与双滞环DITC控制相结合的控制方法。根据转矩误差的大小及时调整施加在绕组两端的平均电压,并通过重新划分导通区域,根据区域特点制定合适的控制策略,以达到抑制转矩脉动的目的。基于MATLAB/Simulink构建系统的仿真模型,比较传统DITC控制与新型PWM-DITC控制的转矩脉动,并探究不同滞环宽度和开关频率对转矩脉动的影响。仿真结果表明:本文PWM-DITC控制方法克服了传统DITC控制不能根据转矩误差的大小及时提供给绕组两端合适电压的缺点,有效地抑制了开关磁阻电机的转矩脉动,相比于传统DITC控制,转矩脉动降低幅度在8~16个百分点。 展开更多
关键词 开关磁阻电机(SRM) 转矩脉动 直接瞬时转矩控制(DITC) 软斩波pwm控制
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PWM驱动的直流电机线束串扰仿真分析与试验验证
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作者 张彬 李强 +1 位作者 朱冬冬 楚艳钢 《环境技术》 2025年第5期105-111,共7页
在车载电气系统中,由PWM驱动的直流电机系统是一稳定的骚扰源,在测试及用户使用中,经常因PWM驱动的电机线束串扰导致敏感电路内波形畸变,车辆报故障,分析其原因为电机中产生的振铃通过线束分布参数串扰至敏感电路中。本文基于骚扰源仿... 在车载电气系统中,由PWM驱动的直流电机系统是一稳定的骚扰源,在测试及用户使用中,经常因PWM驱动的电机线束串扰导致敏感电路内波形畸变,车辆报故障,分析其原因为电机中产生的振铃通过线束分布参数串扰至敏感电路中。本文基于骚扰源仿真模型,研究建立线束串扰仿真模型,通过仿真数据与实际采集数据对比,验证了模型的准确性。并采用验证后的模型分析了在线束串扰中的主要影响参数,提出优化线束串扰的方法。 展开更多
关键词 pwm 电机系统 分布参数 线束串扰
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基于单环控制结构的三相PWM整流器离散滑模直接功率控制
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作者 侯波 刘唐旺 《电子测量技术》 北大核心 2025年第21期129-138,共10页
针对双环控制结构下三相PWM整流器直接功率控制存在的控制结构复杂、动态响应速度慢等问题,同时考虑控制算法在微处理器中应用的适用性,提出一种基于离散非线性扰动观测器的三相PWM整流器单环离散滑模直接功率控制方法。首先,将整流器... 针对双环控制结构下三相PWM整流器直接功率控制存在的控制结构复杂、动态响应速度慢等问题,同时考虑控制算法在微处理器中应用的适用性,提出一种基于离散非线性扰动观测器的三相PWM整流器单环离散滑模直接功率控制方法。首先,将整流器直流侧功率模型和网侧有功功率模型视为整体,得到直流侧-网侧有功功率模型;其次,设计了一种离散非线性扰动观测器,并构建了一种含有功率扰动估计的新型滑模面,以提高单环离散滑模控制的抗功率扰动能力,减小其功率跟踪误差;最后,在处理器在环测试平台上对双环PI控制、传统离散滑模控制和本文所提控制进行了对比。相比于双环PI控制,阻性负载突变和恒功率负载突变时,所提控制的调节时间和电压跌落分别减少了90%、35.7%和91%、41%。稳态运行时,所提控制的电流总谐波畸变率与传统离散滑模控制和双环PI控制相比分别减少了36%和15%。测试结果验证了所提控制方法的有效性和优越性。 展开更多
关键词 三相pwm整流器 离散滑模控制 直接功率控制 非匹配扰动
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基于线性自抗扰和复合控制的单相PWM整流器研究 被引量:1
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作者 王晓雷 张雷 +1 位作者 郭飞亚 林智博 《机械工程与自动化》 2025年第1期31-34,37,共5页
为了提高整流器输出直流电压的抗干扰能力,以及降低交流输入侧电流的谐波含量,对其采用电流内环重复控制(Repeat Control,RC)+PI(Proportional Integral,PI)的复合控制及电压外环线性自抗扰控制(Linear Active Disturbance Rejection Co... 为了提高整流器输出直流电压的抗干扰能力,以及降低交流输入侧电流的谐波含量,对其采用电流内环重复控制(Repeat Control,RC)+PI(Proportional Integral,PI)的复合控制及电压外环线性自抗扰控制(Linear Active Disturbance Rejection Control,LADRC)的控制方法。首先建立单相PWM整流器的数学模型,并在此基础上设计了LADRC电压外环和复合控制电流内环的控制方案。对其仿真和实验结果与PI双闭环控制结果进行对比,结果表明:LADRC电压外环控制可以有效提高直流侧电压的稳定性和响应速度以及受到扰动时的调节能力,与此同时复合控制电流内环不仅降低了交流侧电流的谐波含量,对周期性扰动的抑制作用也得到增强,同时其动态性能也得到提高。 展开更多
关键词 pwm整流器 PI控制 重复控制 LADRC
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单相两电平PWM整流器传感器故障诊断与容错控制
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作者 李常贤 李征宇 孙燕楠 《大连交通大学学报》 2025年第6期149-156,共8页
为了保证高速动车组牵引系统的可靠运行,以单相两电平整流器为研究对象,针对其中的网侧电流传感器和中间直流链电压传感器,提出了一种基于Luenberger观测器的改进故障诊断方法。通过建立整流器状态空间模型,设计了全状态可观且收敛迅速... 为了保证高速动车组牵引系统的可靠运行,以单相两电平整流器为研究对象,针对其中的网侧电流传感器和中间直流链电压传感器,提出了一种基于Luenberger观测器的改进故障诊断方法。通过建立整流器状态空间模型,设计了全状态可观且收敛迅速的观测器,准确估计网侧电流值和直流链电压值。在此基础上,通过重构控制量,将传感器的采集值与观测器的估计值作差建立电流与电压残差,从而实现快速容错控制。仿真结果表明,系统可在故障发生后短时内完成故障诊断,通过容错控制单元使系统快速恢复稳定运行。所提方法对变流器故障诊断具有一定的参考价值。 展开更多
关键词 单相pwm整流器 Luenberger观测器 传感器故障 故障诊断 容错控制
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逆变器中应用PWM展频降低EMI的方式研究 被引量:1
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作者 赵武玲 《机电信息》 2025年第12期14-17,共4页
在现代电力系统中,无论是大电流、高电压、快速运行的电源开关系统,还是高速电机的驱动系统,电磁干扰的传播一直是系统设计的难点。鉴于此,介绍了通过控制高速开关核心模块PWM(脉宽调制)的展频方式来减少EMI(电磁干扰)的方法,对周期展... 在现代电力系统中,无论是大电流、高电压、快速运行的电源开关系统,还是高速电机的驱动系统,电磁干扰的传播一直是系统设计的难点。鉴于此,介绍了通过控制高速开关核心模块PWM(脉宽调制)的展频方式来减少EMI(电磁干扰)的方法,对周期展频、随机展频、混沌展频、混合展频等方式进行了介绍,分析了各方式的优缺点,对选择合适的展频技术方案有一定的指导意义。 展开更多
关键词 电磁干扰(EMI) 脉宽调制(pwm) 展频
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Dynamics Model of Carrier-based Aircraft Landing Gears Landed on Dynamic Deck 被引量:11
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作者 Zhang Wen,Zhang Zhi,Zhu Qidan,Xu Shiyue Department of Automation,Harbin Engineering University,Harbin 150001,China 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2009年第4期371-379,共9页
In order to study the carrier-based aircraft landing laws landed on the carrier, the dynamics model of carrier-based aircraft landing gears landed on dynamic deck is built. In this model, the interactions of the carri... In order to study the carrier-based aircraft landing laws landed on the carrier, the dynamics model of carrier-based aircraft landing gears landed on dynamic deck is built. In this model, the interactions of the carrier-based aircraft landing attitude and the damping force acting on landing gears are considered, and the influence of dynamic deck is introduced into the model through the deck normal vectors. The wheel-deck coordinate system is put forward to solve the complex simulation problem of force-onwheel which comes from the dynamic deck. At last, by simulation, it is demonstrated that the model can be applied to landing attitude when the carrier-based aircraft is landing on the dynamic deck, it is also proved that the model is comprehensive and suitable for any abnormal landing situation. 展开更多
关键词 carrier-based aircraft landing gear DECK wheel-deck coordinate system LANDING
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基于梅森旋转算法的双随机PWM电机噪声抑制策略
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作者 高剑 刘晨旭 +1 位作者 刘锟 吕达飞 《防爆电机》 2025年第5期1-9,共9页
针对采用传统空间矢量脉宽调制(SVPWM)技术调制逆变器开关管时,较高的电压变化率会导致能量集中在载波频率及其倍频从而产生高频脉冲谐波的问题,在传统线性同余法的基础上提出了一种基于梅森旋转算法的双随机调制策略。通过分析梅森旋... 针对采用传统空间矢量脉宽调制(SVPWM)技术调制逆变器开关管时,较高的电压变化率会导致能量集中在载波频率及其倍频从而产生高频脉冲谐波的问题,在传统线性同余法的基础上提出了一种基于梅森旋转算法的双随机调制策略。通过分析梅森旋转算法产生伪随机数的原理,来弥补传统线性同余法不能最大程度地发挥随机脉宽调制技术(PWM)策略的谐波分散特性的不足。最后采用仿真对比不同调制策略下电流的傅里叶分析频谱图,验证该方法的有效性及优越性。仿真结果表示,采用梅森旋转调制策略对开关频率次谐波幅值以及开关频率次二倍频的谐波幅值抑制效果更为优异,能够大幅度抑制由PWM谐波引起的噪声,提升电机系统整体性能。 展开更多
关键词 空间矢量脉宽调制 线性同余法 双随机调制策略 梅森旋转算法 pwm谐波
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Guidance and Control Techniques of Carrier-Based Aircraft for Automatic Carrier Landing 被引量:10
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作者 Zhen Ziyang Zhang Zhibin Zhang Junhong 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第6期600-608,共9页
We summarize the guidance and control techniques of automatic carrier landing for carrier-based aircraft.First,we analyze the carrier landing operations of the manned fixed-wing aircraft,unmanned fixed-wing aircraft a... We summarize the guidance and control techniques of automatic carrier landing for carrier-based aircraft.First,we analyze the carrier landing operations of the manned fixed-wing aircraft,unmanned fixed-wing aircraft and helicopters.Second,we look into the navigation and guidance system and the flight control methods for current different aircraft.Finally,we draw several conclusions of the development prospects for aircraft carrier landing,including the precision landing control techniques,precision approach and landing guidance techniques,and adaptive,reconfigurable and intelligent flight control techniques. 展开更多
关键词 carrier-based aircraft automatic carrier landing GUIDANCE flight control
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Modeling of Carrier-based Aircraft Ski Jump Take-off Based on Tensor 被引量:8
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作者 刘伟伟 屈香菊 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2005年第4期326-335,共10页
A general mathematical model of carrier-based aircraft ski jump take-off is derived based on tensor. The carrier, the aircraft body and the movable parts of the landing gears are treated as independent entities. These... A general mathematical model of carrier-based aircraft ski jump take-off is derived based on tensor. The carrier, the aircraft body and the movable parts of the landing gears are treated as independent entities. These entities are assembled into a multi-rigid-body system with flexible links. Dynamical equations of each entity are derived on the basis of the Newton law and the Euler transformation. Using the invariance property of the tensor, the dynamical and kinematical equations are converted to tensor forms which are invariant under time-dependent coordinate transformations. Then the tensor-formed equations are expressed by the matrix operation. Differential equation group of the matrix form is formulated for the programming. The closure of the model is discussed, and the simulation results are given. 展开更多
关键词 mathematical model TENSOR carrier-based aircraft ski jump TAKE-OFF
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Multi-body dynamic system simulation of carrier-based aircraft ski-jump takeoff 被引量:6
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作者 Wang Yangang Wang Weijun Qu Xiangju 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第1期104-111,共8页
The flight safety is threatened by the special flight conditions and the low speed of carrier-based aircraft ski-jump takeoff. The aircraft carrier motion, aircraft dynamics, landing gears and wind field of sea state ... The flight safety is threatened by the special flight conditions and the low speed of carrier-based aircraft ski-jump takeoff. The aircraft carrier motion, aircraft dynamics, landing gears and wind field of sea state are comprehensively considered to dispose this multidiscipline intersection problem. According to the particular naval operating environment of the carrier-based aircraft ski-jump takeoff, the integrated dynamic simulation models of multi-body system are developed, which involves the movement entities of the carrier, the aircraft and the landing gears, and involves takeoff instruction, control system and the deck wind disturbance. Based on Matlab/Simulink environment, the multi-body system simulation is realized. The validity of the model and the rationality of the result are verified by an example simulation of carrier-based aircraft ski-jump takeoff. The simulation model and the software are suitable for the study of the multidiscipline intersection problems which are involved in the performance, flight quality and safety of carrier-based aircraft takeoff, the effects of landing gear loads, parameters of carrier deck, etc. 展开更多
关键词 Aircraft carrier carrier-based aircraft MODELS Multi-body dynamics SIMULATION Ski-jump takeoff
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Parameter Optimization of Nose Landing Gear Considering Both Take-off and Landing Performance of Catapult Take-off Carrier-Based Aircraft 被引量:5
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作者 Zhang Ming Nie Hong He Zhihang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第2期187-198,共12页
Optimization of the parameters of landing gear systems with double-stage air springs of catapult take-off carrier-based aircraft is here studied based on the mathematical equations of the classic dual mass spring-damp... Optimization of the parameters of landing gear systems with double-stage air springs of catapult take-off carrier-based aircraft is here studied based on the mathematical equations of the classic dual mass spring-damper dynamic model.Certain standards for both take-off and landing performance are put forward.The contradictory factors between take-off and landing processes are analyzed.The optimization of oil in the pin area and the area near the rear oil hole is performed.Then these optimized parameters are used to assess the influence of the initial pressure of the low chamber,the ratio of the high chamber to the low chamber,and the tire inflation pressure on the performance of arresting landing and catapult take-off.The influences of these parameters on carrier-based aircraft and the aircraft-carrier on aircraft catapult take-off is also assessed.Based on the results of the simulation,respective take-off criteria must be drafted considering different types of aircraft and different take-off load cases,all of which must be matched to parameters relevant to catapult take-off. 展开更多
关键词 carrier-based AIRCRAFT BUFFER PERFORMANCE fast-extension PERFORMANCE AIRCRAFT design optimization sensitivity analysis
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错相位驱动PWM变量喷雾系统设计与试验 被引量:1
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作者 张春凤 张萌 +3 位作者 邹伟 翟长远 张弛 赵春江 《农业工程学报》 北大核心 2025年第16期25-34,共10页
针对脉宽调制(pulse width modulation, PWM)变量喷雾系统电磁阀同步启闭造成管路压力波动严重的问题,该研究提出一种基于错相位驱动的压力波动抑制方法,基于C37控制器开发了支持不同相位差驱动的PWM变量控制系统,设计并搭建试验平台,开... 针对脉宽调制(pulse width modulation, PWM)变量喷雾系统电磁阀同步启闭造成管路压力波动严重的问题,该研究提出一种基于错相位驱动的压力波动抑制方法,基于C37控制器开发了支持不同相位差驱动的PWM变量控制系统,设计并搭建试验平台,开展PWM变量喷雾系统压力波动特性试验、雾化特性试验及雾滴沉积试验。压力波动试验结果表明,错相位驱动方式有效降低了系统压力波动峰峰值和变异系数,且随着占空比的增加,压力波动降低趋势逐渐缩小。当占空比为20%和70%时,错相位120°的压力波动变异系数(CV)比同相位驱动分别减小66.61%和19.48%。占空比对变异系数影响最小的相位差区间是60°~90°驱动,相位差120°时,不同占空比下系统压力波动CV值均最小;对比试验结果表明,错相位驱动的系统雾滴粒径统计项均略低于同相位驱动,错相位驱动系统的雾滴相对跨度(RS)低于同相位驱动,占空比50%时,RS下降最多,为5.56%;雾滴沉积对比试验结果表明,错相位驱动PWM喷雾系统的雾滴覆盖率变异系数相比同相位驱动方式减小了31.75%,错相位驱动方式可有效改善PWM变量喷药系统低频控制条件下药液沉积均匀性。研究结果可为PWM变量喷雾技术研发与应用提供依据,为精准变量施药装置的进一步优化提供技术支撑。 展开更多
关键词 pwm 变量喷雾 压力波动 雾化特性 雾滴粒径 雾滴沉积
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Dynamics Analysis of Carrier-Based Aircraft with Off-Center Catapult Launch 被引量:2
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作者 ZHOU Jin ZHU Jianhui TONG Mingbo 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第3期468-478,共11页
In order to enhance the safety of the catapult launch of the carrier-based aircraft,the catapult launch multibody dynamic model is established aiming at the problem of off center catapult launch.The whole catapult pro... In order to enhance the safety of the catapult launch of the carrier-based aircraft,the catapult launch multibody dynamic model is established aiming at the problem of off center catapult launch.The whole catapult process including four stages which are buffering,tensioning,releasing and taxiing is taken into consideration and the body dynamics of the off-center catapult during each stage is analyzed.The catapult launch dynamic differences between the conditions only considering taxiing and that considering four stages are compared,and the effects of the different initial off center distances considering four stages on the attitude,landing gear load and acceleration of the carrier based aircraft during catapult launch are discussed.The results show that only considering taxiing may underestimate the dynamics of the carrier-based aircraft substantially.When taking four stages into consideration,the initial off-center distance has small influence on the aircraft dynamic characteristics during buffering and tensioning but has larger influence on that during releasing and taxiing.The increase of the off-center distance will cause the enhancement of the aircraft rolling and yawing,which may lead to the load difference between the left and right landing gears and the increase of the aircraft lateral acceleration.The establishment and simulation of the catapult launch multi body dynamic model founded on buffering,tensioning,releasing and taxiing provide reference for the carrier-based aircraft design and analysis of the catapult launch dynamics. 展开更多
关键词 carrier-based aircraft catapult LAUNCH OFF center distance ATTITUDE angle LANDING GEAR
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DYNAMIC RESPONSE ANALYSIS OF CARRIER-BASED AIRCRAFT DURING LANDING 被引量:1
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作者 段萍萍 聂宏 魏小辉 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2013年第4期306-316,共11页
In view of the complexity of landing on the deck of aircraft carrier,a systematic model,composed of sixdegree-of-freedom mathematic model of carrier-based aircraft,four-degree-of-freedom model of landing gears and six... In view of the complexity of landing on the deck of aircraft carrier,a systematic model,composed of sixdegree-of-freedom mathematic model of carrier-based aircraft,four-degree-of-freedom model of landing gears and six-degree-of-freedom mathematic model of carrier,is established in the Matlab-Simulink environment,with damping function of landing gears and dynamic characteristics of tires being considered.The model,where the carrier movement is introduced,is applicable for any abnormal landing condition.Moreover,the equations of motion and relevant parameter are also derived.The dynamic response of aircraft is calculated via the variable step-size RungeKuta algorithm.The effect of attitude angles of aircraft and carrier movement during the process of landing is illustrated in details.The analytical results can provide some reference for carrier-based aircraft design and maintenance. 展开更多
关键词 carrier-based aircraft LANDING carrier movement dynamic response landing gear
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Optimal Preview Control for Automatic Carrier Landing System of Carrier-Based Aircraft with Air Wake 被引量:1
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作者 Li Meng Zhen Ziyang +2 位作者 Gong Huajun Hou Min Huang Shuhong 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第6期659-668,共10页
Carrier-based aircraft carrier landing is a special kind of tracking control problem and not suitable for classical control methods,which may miss the desired performance or result in overdesign.Therefore,we present a... Carrier-based aircraft carrier landing is a special kind of tracking control problem and not suitable for classical control methods,which may miss the desired performance or result in overdesign.Therefore,we present an optimal preview control for automatic carrier landing system(ACLS)by using state information of system,as well as future reference information,which can avoid the shortcomings of classical control methods.Since the flight performance of carrier-based aircraft is disturbed by air wake when the aircraft flies near the area of carrier stern,we design a disturbance rejection strategy to ensure that aircraft track the glide path with high precision and robustness.Further,carrier-based aircraft is a complex nonlinear system.However,the nonlinear model of carrier-based aircraft can be linearized at equilibrium landing state and decoupled into the longitudinal model and the lateral model.Therefore,an optimal preview control system is designed.The simulation results of a carrier-based aircraft show that the optimal preview control system can effectively suppress air wake.Tracking accuracy of optimal preview controller is higher than that of the proportional integral differential(PID)control system. 展开更多
关键词 carrier-based aircraft carrier landing optimal control preview control nonlinear model
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