检索结果-内蒙古大学图书馆

Flow control characteristics of the digital and mechanical redundancy control electric modulation valve

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第8期23卷 599-609页

作者： He LIU Bin ZHAO Bo WANG Long QUAN Yun-xiao HAO Yun-wei LI Key Laboratory of Advanced Transducers and Intlligent Control System of Ministry of Education and Shanxi Province Taiyuan University of TechnologyTaiyuan 030024China Deparment of Electrical and Computer Engineering University of AlbertaEdmonton ABT6G1H9Canada

The electrical modulation valve can provide proportional output valve element displacement,flow,or pressure according to a continuously changing input electrical *** is the core component of electro-hydraulic proportional control *** remove the influence of pressure difference changes on the output flow,the traditional scheme is to use a pressure compensation valve,which increases the difficulty of both manufacturing and maintaining the *** solve this problem,a method of digital and mechanical redundancy control flow is *** sensors are installed at the inlet and outlet of the valve,and the controller adjusts the displacement of the valve element according to the pressure difference between the valve ports to realize high-precision control of the flow.A pressure compensation valve is installed in front of the valve,and a three-way solenoid valve is used to control the working of the compensation *** the case of sensor failure,the valve is switched to the mechanical compensation differential pressure mode,to control the flow and to achieve redundancy *** system security is thereby *** feasibility of this scheme is verified through simulation and *** results show that,both for digital compensation and mechanical compensation,the output flow can be kept constant when the pressure difference changes,and the system has good static and dynamic *** principle can be applied to the displacement-flow feedback type electrical modulation valve,and can realize accurate control of the flow of the pilot valve and,finally,accurate control of the flow in the main valve.

关键词： Electrical modulation valve control characteristics Co-simulation Redundancy control

来源：评论

学校读者我要写书评

暂无评论

Research Advances on Passive Knee Joints Rehabilitation Device

引用

Recent Patents on Mechanical Engineering 2022年第2期15卷 106-121页

作者： Jiang, Jingang Gao, Ziwen Wu, Dianhao Yu, Xiaoyang Guo, Yafeng Key Laboratory of Advanced Manufacturing and Intelligent Technology Ministry of Education Harbin University of Science and Technology Harbin150080 China Intelligent Machine Institute Harbin University of Science and Technology Harbin150080 China School of Measurement-Control Tech and Communications Engineering Harbin University of Science and Technology Harbin150080 China

Background: After a smooth development of life expectancy per capita and fertility in the nineteenth century, the global population increased in size. Along with the demographic shift in the late nineteenth century, the phenomenon of population aging began to appear in developed countries. A survey from UN reports that by 2050, one in six people worldwide will be over 65 years old (16%), compared to 11 (9%) in 2019. According to another survey, 55% of people over the age of 60 suffer from joint diseases, and the number of people suffering from stroke, arthritis and other knee diseases will also increase accordingly. Objective: An overview of the classification and characteristics of today's knee rehabilitation devices and future developments. Methods: This review discusses the existing knee rehabilitation devices, including various prod-ucts on the market, patents and some conceptual devices, in the context of the structural characteristics of the knee joint and the rehabilitation requirements of different knee conditions or after knee arthroplasty, and systematically introduces their structural features, differences and the rehabilitation effects achieved. Results: A comparative analysis of three types of passive knee rehabilitation devices according to their use was conducted to summarize the typical characteristics. The problems that exist in today's rehabilitation devices are also analyzed, and their development trends are looked forward to. Conclusion: Knee rehabilitation equipment has a high degree of structural richness, but it does not achieve a good balance of convenience, comfort and functionality, and there should be some room for improvement in the materials, volume of the power source and transmission form of the power system. There will be a good development in the future of knee joint recovery. © 2022 Bentham Science Publishers.

关键词： Surveys

来源：评论

学校读者我要写书评

暂无评论

InGaAlAs/InP MQW transistor lasers based on step-ridge waveguides

IEEE Electron Device Letters

引用

IEEE Electron Device Letters 2025年

作者： Liu, Yijia Qiao, Lijun Tang, Xin Liang, Song Zhang, Mingjiang Taiyuan University of Technology College of Physics and Optoelectronics Taiyuan030024 China Ministry of Education Taiyuan University of Technology Key Laboratory of Advanced Transducers and Intelligent Control System Shanxi Taiyuan030024 China Chinese Academy of Sciences Key Laboratory of Optoelectronic Materials and Devices Beijing100083 China University of Chinese Academy of Sciences Center of Materials Science and Optoelectronics Engineering Beijing100049 China

We propose and numerically investigate a new step-ridge-waveguide InGaAlAs/InP multi-quantum well (MQW) transistor laser (TL). The carrier nonradiative recombination centers caused by the exposed deep-ridge waveguide sidewall significantly degrade the optoelectronic performance of the TLs. The step-ridge-waveguide structure guides carriers through the center portion of the ridge waveguide, thereby effectively mitigating the effect of the nonradiative recombination defects. Simulation results show that the optoelectronic characteristics of the step-ridge TL are far better than those of the conventional deep-ridge TL, and the current amplification factor of the step-ridge TL is not affected by the laser excitation. This structure provides a new option for the simultaneous enhancement of the optoelectronic performance of TLs. © 1980-2012 IEEE.

关键词： Laser excitation

来源：评论

学校读者我要写书评

暂无评论

Optimal Tracking Performance of Networked control systems Under DoS and Its Applications

Optimal Tracking Performance of Networked Control Systems Un...

引用

2024 China Automation Congress, CAC 2024

作者： Ren, Xinyu Li, Bo Zhao, Feng Chen, Xiangyong Zhang, Xianhe Jiang, Xiaowei School of Automation China University of Geosciences Hubei Key Laboratory of Advanced Control and Intelligent Automation of Complex Systems Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of Education Wuhan China School of Finance Anhui University of Finance and Economics Bengbu China Key Laboratory of Complex systems and Intelligent Computing in Universities of Shandong Linyi University Linyi China School of Automation and Electrical Engineering Key Laboratory of Complex systems and Intelligent Computing in Universities of Shandong Linyi University Linyi China School of Electrical Engineering and Automation Hubei Normal University Huangshi China

ISBN: (纸本)9798350368604

This paper investigates the optimal tracking performance (OTP) of multiple-input multiple-output (MIMO) discrete networked control systems (NCSs) under the influence of Denial of Service (DoS) attack, channel noise, and bandwidth constraints. The channel noise is assumed to be additive Gaussian white noise (AWGN). Due to the randomness of DoS attack, a Bernoulli distribution is used for DoS modeling. Utilizing frequency domain analysis methods, coprime factorization, all-pass decomposition, and Youla parameterization, an explicit expression for the optimal tracking performance (OTP) of the system under the two-degree-of-freedom (TDOF) controller is derived. The analysis indicates that non-minimum phase (NMP) zeros, unstable poles (UPs), DoS attack, and network constraints affect the OTP of NCSs. Finally, the theoretical results are validated through simulations of MIMO NCS and vehicle control system. © 2024 IEEE.

关键词： White noise

来源：评论

学校读者我要写书评

暂无评论

Cascading Failure Screening Based on Gradient Boosting Decision Tree for HVDC Sending-End systems with High Wind Power Penetration

引用

IEEE Transactions on Power systems 2025年

作者： Liu, Tianhao Yan, Jiongcheng Liu, Yutian Chung, Chi Yung Shandong University Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Jinan China The Hong Kong Polytechnic University Department of Electrical and Electronic Engineering Kowloon Hong Kong

In LCC-HVDC sending-end AC systems, cascading failures combined with the dynamic response of wind turbines (WTs) can lead to HVDC commutation failures. The resulting transient voltage disturbances cause WT tripping in sending-end systems. Cascading failures that involve the interaction between WTs and HVDC significantly limit the wind power transmitted by HVDC systems. This paper proposes an online cascading failure screening method based on gradient boosting decision tree (GBDT) for HVDC sending-end systems with large-scale WTs. First, a confidence level-based WT tripping model is proposed for cascading failure risk assessment considering a typical cascading failure propagation pattern. Then, Monte Carlo tree search is improved using a contrastive pruning technique to generate evenly distributed samples of cascading failures offline. Dynamic insecure scenarios are quickly identified using an improved support vector machine. Finally, GBDT is utilized to screen for cascading failures online by predicting subsequent high-risk failures using operating features. A dynamic weighting technique is proposed for GBDT to improve the fault prediction accuracy. Simulation results of a modified New England test system and the Ningxia provincial power grid in western China demonstrate that the proposed method can quickly screen for cascading failures considering the dynamic interaction between WTs and HVDC. © 1969-2012 IEEE.

关键词： Risk assessment

来源：评论

学校读者我要写书评

暂无评论

A Novel Integrated Energy Management Strategy of Energy Storage system for a Pure Electric-Driven Mining Hydraulic Excavator

引用

Chinese Journal of Mechanical Engineering 2025年第2期 465-481页

作者： Tao Qin Yunhua Li Long Quang Yu Yao Liman Yang School of Automation Science and Electrical Engineering Beihang University Beijing Tianma Intelligent Control Technology Co. Ltd. Key Lab of Advanced Transducers and Intelligent Control System of Ministry of Education Taiyuan University of Technology

Using electric motors instead of diesel engines as the driving system for mining excavators can reduce the energy consumption and operating costs. However, pure electric-driven mining excavators are prone to unexpected power outages in mines because of drastic changes in load power, leading to significant fluctuations in the power demand of the grid, which in turn affects production. To solve the above problem, a pure electric-driven mining hydraulic excavator based on electric-motor-driven swing platform and hydraulic pumps was used as the research object. Moreover, supercapacitors and DC/DC converter, as the energy storage system(ESS) adjust the output power of the grid and recover the braking kinetic energy of the swing platform. Subsequently, a novel integrated energy management strategy for a DC bus voltage predictive controller based on the power feedforward of fuzzy rules is proposed to run mining excavators efficiently and reliably. Specifically, the working modes of the ESS are determined by the DC bus voltage and state of charge(SOC) of the supercapacitor. Next, the output power of the supercapacitor and the DC bus voltage were controlled by adjusting the charging and discharging currents of the DC/DC converter using a predictive controller and fuzzy rules. In addition, a digital prototype of the excavator was verified using an original machine test. The performance of the different strategies and driven systems were analyzed using digital prototypes. The results showed that, compared with traditional excavators with diesel engines, the operational cost of the developed excavators was reduced by 54.02%. Compared to pure electric-driven excavators without an ESS, the peak power of the grid for the developed excavators was reduced by 10%. This study designed an integrated energy management strategy for a pure electric mining excavator that can regulate the power output of the grid and maintain the stability of the bus voltage and SOC of the ESS.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Optimal Scheduling Strategy of Limited Electricity Based on Energy Sharing of Multi-microgrid

Optimal Scheduling Strategy of Limited Electricity Based on ...

引用

2022 Chinese Automation Congress, CAC 2022

作者： Zeng, Zihan Li, Danyun Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Wuhan430074 China Ministry of Education Wuhan430074 China Engineering Research Center of Intelligent Technology for Geo-Exploration Wuhan China

ISBN: (纸本)9781665465335

In the environment of limited electricity supply in distribution network, due to the limitation of its own power capacity and the uncertainty of new energy output, there will be insufficient electricity supply in microgrid, which will affect the economy and comfort of users in microgrid system. Therefore, aiming at the situation of limited electricity supply in distribution network, multi-microgrid system is taken as the research object, and the cooperative game method is adopted to realize the energy sharing of multi-microgrid system, and then the limited electricity optimal dispatching model of multi-microgrid system is constructed to realize the reasonable power distribution for different types of loads. Finally, the simulation results show that this strategy can effectively realize power sharing, reduce outage loss and improve user satisfaction. © 2022 IEEE.

关键词： Electric power distribution

来源：评论

学校读者我要写书评

暂无评论

Structure design and kinematics modeling of a new continuum parallel robot 20

Structure design and kinematics modeling of a new continuum ...

引用

20th IEEE International Conference on Mechatronics and Automation, ICMA 2023

作者： Wang, Xinjie Li, Bin Ma, Yue Peng, Wei Peng, Pai Wang, Jinyuan Tianjin University of Technology Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin300384 China Tianjin University of Technology National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin China

ISBN: (纸本)9798350320831

Compared with the traditional rigid robots, the continuum robot has been widely studied because of its advantages of compact design and flexible motion. The design of continuum parallel robots are similar to that of the traditional rigid-link parallel robot, and the precision, stability and strength characteristics of rigid-link parallel robots are combined with the compactness and flexibility characteristics of continuum robots. In recent research advances, it is well appreciated to suggest that the use of parallel continuum robots with passive supports is supported by elastic rods. The passive branch undergoes deformation along its entire length and uses complex formulas to describe its shape and kinematics. According to different methods, this paper proposes the design of a parallel robot dual continuum translation passive branch chain. This continuum joint will assume a constant curvature bend and use this assumption for kinematic modeling. Since the continuum joint is a flexible joint that utilizes the characteristics of new materials, it uses material deformation to replace the motion pair, which successfully realizes that the passive branch joint can replace the universal joint and the ball hinge in the parallel robot, and the joint can be bent more than 90 0 to achieve a larger range of workspace. Each passive branch of the new continuum robot is a continuum structure composed of two mutually coupled flexible hinge joints, and the translational motion of the end effector is inherently realized by using its material properties. The paper includes a new mechanism description and kinematics modeling. © 2023 IEEE.

关键词： Kinematics

来源：评论

学校读者我要写书评

暂无评论

Gait Planning and Simulation of 3-RRP Legged Mobile Robot 20

Gait Planning and Simulation of 3-RRP Legged Mobile Robot

引用

20th IEEE International Conference on Mechatronics and Automation, ICMA 2023

作者： Wang, Jinyuan Li, Bin Ma, Yue Wang, Xinjie Peng, Pai Peng, Wei Tianjin University of Technology Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin300384 China Tianjin University of Technology National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin China

ISBN: (纸本)9798350320831

In order to meet the requirements of keeping the body posture level with the ground during the movement of the quadruped robots, this paper designs a quadruped robot with three joints and three degrees of freedom in each leg, which is a 3-RRP kinematic chain. The legs and body of the quadruped robot are virtually modeled by SolidWorks. Combining the forward and inverse kinematics analysis, the reasonable and ideal foot trajectory and body motion trajectory are planned in Matlab. The gait stability is based on the ZMP stability criterion and is quantified by the stability margin. According to the structural characteristics of the quadruped robot in this paper, the body posture adjustment strategy is proposed. Finally, the simulation is carried out under the two gait plannings of straight driving and turning using ADAMS. The simulation results show that the quadruped robot has a reasonable walking gait on the flat road surface with little impact on the body. The minimum stability margin of the strategy with body adjustment is improved compared with the strategy without body adjustment. © 2023 IEEE.

关键词： Stability criteria

来源：评论

学校读者我要写书评

暂无评论

Maxwell's demon-like nonreciprocity by non-Hermitian gyrotropic metasurfaces

引用

Physical Review Research 2021年第2期3卷 L022006-L022006页

作者： Wenyan Wang Wang Tat Yau Yanxia Cui Jin Wang Kin Hung Fung College of Physics and Optoelectronics Key Lab of Advanced Transducers and Intelligent Control System of Ministry of Education Taiyuan University of Technology Taiyuan 030024 China Department of Applied Physics The Hong Kong Polytechnic University Hong Kong China School of Physics Southeast University Nanjing 211189 China

We show that Maxwell's demon-like nonreciprocity can be supported in a class of non-Hermitian gyrotropic metasurfaces in the linear regime. The proposed metasurface functions as a transmission-only Maxwell's demon operating at a pair of photon energies. Based on multiple scattering theory, we construct a dual-dipole model to explain the underlying mechanism that leads to the antisymmetric nonreciprocal transmission. The results may inspire new designs of compact nonreciprocal devices for photonics.

关键词： Geometrical & wave optics Light propagation, transmission & absorption Magneto-optical effect Magnons Photonic crystals

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：