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Interaction and coordinated development between desertification control and social economy in Xizang,China
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作者 ZHU Cai-xia ZHENG Yu-jie +1 位作者 LIU Si-yu QIN Tao 《Ecological Economy》 2024年第2期160-177,共18页
Based on the general requirements of the coordinated development of"ecological livable"and"affluent life"in the rural revitalization strategy,the evaluation index system of desertification control ... Based on the general requirements of the coordinated development of"ecological livable"and"affluent life"in the rural revitalization strategy,the evaluation index system of desertification control was constructed,the interaction between desertification control and regional social economy and the internal space-time coordination mechanism were explored,and the quality of desertification control and its coordination degree with regional economic development were quantitatively analyzed.The decoupling mechanism of desertification governance society economy system were analyzed,and the high level for the government to promote desertification governance,constructing ecological economy coordinated development pattern to provide decision basis to Xizang desertification governance-social economic system interaction and coupling coordination development as the research object,introducing the coupling decoupling model to measure the coupling coordination model and system coordination and decoupling decoupling.Desertification control in Xizang shows a trend of gradual improvement,but the overall level is still not high and there is a lot of room for optimization.The coupling coordination degree of desertification control-social and economic system is in a steady fluctuation trend,rising from D value less than 0.55 in 2004 to 0.87 in 2018,in a state of coordinated development(good),and grey prediction analysis shows that D value is in a continuous rise.The coupling coordination degree of the six prefecture-level cities in Xizang and Ngari region is different in time and space,but the overall development trend is coordinated.The development index of desertification control and the socio-economic development index show the interaction of strong decoupling,strong negative decoupling and weak decoupling,and there are interaction effects of desertification control,economic development and social development at different scales. 展开更多
关键词 desertification control coupling coordination model decoupling model economic development
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Group Hybrid Coordination Control of Multi-Agent Systems With Time-Delays and Additive Noises
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作者 Chuanjian Li Xiaofeng Zong 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第3期737-748,共12页
A new kind of group coordination control problemgroup hybrid coordination control is investigated in this paper.The group hybrid coordination control means that in a whole multi-agent system(MAS)that consists of two s... A new kind of group coordination control problemgroup hybrid coordination control is investigated in this paper.The group hybrid coordination control means that in a whole multi-agent system(MAS)that consists of two subgroups with communications between them,agents in the two subgroups achieve consensus and containment,respectively.For MASs with both time-delays and additive noises,two group control protocols are proposed to solve this problem for the containment-oriented case and consensus-oriented case,respectively.By developing a new analysis idea,some sufficient conditions and necessary conditions related to the communication intensity betw een the two subgroups are obtained for the following two types of group hybrid coordination behavior:1)Agents in one subgroup and in another subgroup achieve weak consensus and containment,respectively;2)Agents in one subgroup and in another subgroup achieve strong consensus and containment,respectively.It is revealed that the decay of the communication impact betw een the two subgroups is necessary for the consensus-oriented case.Finally,the validity of the group control results is verified by several simulation examples. 展开更多
关键词 Additive noises consensus control containment control group hybrid coordination control multi-agent systems(MASs) TIME-DELAYS
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Adaptive signal control and coordination for urban traffic control in a connected vehicle environment: A review
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作者 Jiangchen Li Liqun Peng +4 位作者 Kaizhe Hou Yong Tian Yulin Ma Shucai Xu Tony Z.Qiu 《Digital Transportation and Safety》 2023年第2期89-111,共23页
Existing signal control systems for urban traffic are usually based on traffic flow data from fixed location detectors.Because of rapid advances in emerging vehicular communication,connected vehicle(CV)-based signal c... Existing signal control systems for urban traffic are usually based on traffic flow data from fixed location detectors.Because of rapid advances in emerging vehicular communication,connected vehicle(CV)-based signal control demonstrates significant improvements over existing conventional signal control systems.Though various CV-based signal control systems have been investigated in the past decades,these approaches still have many issues and drawbacks to overcome.We summarize typical components and structures of these existing CV-based urban traffic signal control systems and digest several important issues from the summarized vital concepts.Last,future research directions are discussed with some suggestions.We hope this survey can facilitate the connected and automated vehicle and transportation research community to efficiently approach next-generation urban traffic signal control methods and systems. 展开更多
关键词 Urban traffic signal control Adaptive signal control Signal coordination Connected vehicle-based signal control
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Coordinated control of coastal multi-source multi-load system with desalination load: a review 被引量:3
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作者 Ming Zhong Lu Jin +3 位作者 Jiyu Xia Ling Cheng Peiyu Chen Rong Zeng 《Global Energy Interconnection》 2019年第4期300-309,共10页
Traditional seawater desalination requires high amounts of energy, with correspondingly high costs and limited benefits, hindering wider applications of the process. To further improve the comprehensive economic benef... Traditional seawater desalination requires high amounts of energy, with correspondingly high costs and limited benefits, hindering wider applications of the process. To further improve the comprehensive economic benefits of seawater desalination, the desalination load can be combined with renewable energy sources such as solar energy, wind energy, and ocean energy or with the power grid to ensure its effective regulation. Utilizing energy internet(EI) technology, energy balance demand of the regional power grid, and coordinated control between coastal multi-source multi-load and regional distribution network with desalination load is reviewed herein. Several key technologies, including coordinated control of coastal multi-source multi-load system with seawater desalination load, flexible interaction between seawater desalination and regional distribution network, and combined control of coastal multi-source multi-load storage system with seawater desalination load, are discussed in detail. Adoption of the flexible interaction between seawater desalination and regional distribution networks is beneficial for solving water resource problems, improving the ability to dissipate distributed renewable energy, balancing and increasing grid loads, improving the safety and economy of coastal power grids, and achieving coordinated and comprehensive application of power grids, renewable energy sources, and coastal loads. 展开更多
关键词 DESALINATION Distribution network Power grids multi-source multi-load coordinATED control
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Finite-time coordination control for formation flying spacecraft 被引量:2
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作者 Yong Guo Shenmin Song Liwei Deng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第5期859-867,共9页
This paper investigates a distributed coordination control scheme using an adaptive terminal sliding mode for formation flying spacecraft with coupled attitude and translational dynamics. In order to overcome the sing... This paper investigates a distributed coordination control scheme using an adaptive terminal sliding mode for formation flying spacecraft with coupled attitude and translational dynamics. In order to overcome the singularity of the traditional fast terminal sliding manifold, a novel fast terminal sliding manifold is given. And then, based on the adaptive control method, a continuous robust coordinated controller is designed to compensate external disturbances and to alleviate the chattering phenomenon. The theoretical analysis shows that the coordinated controller can guarantee the finite-time stability of the overall closed-loop system through local information exchange, and numerical simulations also demonstrate its effectiveness. 展开更多
关键词 formation flying coordinated control attitude and translational coupling finite-time stability adaptive control.
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Coordination Control of Greenhouse Environmental Factors 被引量:2
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作者 Feng Chen Yong-Ning Tang Ming-Yu Shen 《International Journal of Automation and computing》 EI 2011年第2期147-153,共7页
Optimal control of greenhouse climate is one of the key techniques in digital agriculture.Greenhouse climate,a nonlinear and uncertain system,consists of several major environmental factors such as temperature,humidit... Optimal control of greenhouse climate is one of the key techniques in digital agriculture.Greenhouse climate,a nonlinear and uncertain system,consists of several major environmental factors such as temperature,humidity,light intensity,and CO 2 concentration.Due to the complex coupled correlations,it is a challenge to achieve coordination control of greenhouse environmental factors.This paper proposes a model-free coordination control approach for greenhouse environmental factors based on Q-learning.Coordination control policy is found through systematic interaction with the dynamic environment to achieve optimal control for greenhouse climate with the control cost constraints.In order to decrease systematic trial-and-error risk and reduce the computational complexity in Q-learning algorithm,case-based reasoning (CBR) is seamlessly incorporated into the Q-learning process.The experimental results demonstrate that this approach is practical,highly effective and efficient. 展开更多
关键词 Q-LEARNING case-based reasoning (CBR) greenhouse environmental factors coordination control coupled correlation trial-and-error.
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An Overview of Research in Distributed Attitude Coordination Control 被引量:2
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作者 Long Ma Haibo Min +2 位作者 Shicheng Wang Yuan Liu Shouyi Liao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2015年第2期121-133,共13页
This paper provides an overview of attitude coordination problems of multi-rigid-body with the goal of promoting research in this area. Theoretical results regarding consensus seeking with different system models, dif... This paper provides an overview of attitude coordination problems of multi-rigid-body with the goal of promoting research in this area. Theoretical results regarding consensus seeking with different system models, different communication topologies, different control goals and different techniques are summarized. And applications of consensus protocols to multirigid-body coordination are investigated. Finally, some future research directions and open problems are also proposed. 展开更多
关键词 Multi-rigid-body attitude coordination coordination control CONSENSUS SYNCHRONIZATION
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Step-coordination Algorithm of Traffic Control Based on Multi-agent System 被引量:1
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作者 Hai-Tao Zhang Fang Yu Wen Li 《International Journal of Automation and computing》 EI 2009年第3期308-313,共6页
Aiming at the deficiency of conventional traffic control method, this paper proposes a new method based on multi-agent technology for traffic control. Different from many existing methods, this paper distinguishes tra... Aiming at the deficiency of conventional traffic control method, this paper proposes a new method based on multi-agent technology for traffic control. Different from many existing methods, this paper distinguishes traffic control on the basis of the agent technology from conventional traffic control method. The composition and structure of a multi-agent system (MAS) is first discussed. Then, the step-coordination strategies of intersection-agent, segment-agent, and area-agent are put forward. The advantages of the algorithm are demonstrated by a simulation study. 展开更多
关键词 Traffic control coordination algorithm multi-agent system (MAS) traffic control system agent.
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Novel ARC-Fuzzy Coordinated Automatic Tracking Control of Four-Wheeled Mobile Robot
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作者 G.Pandiaraj S.Muralidharan 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期3713-3726,共14页
Four-wheeled,individual-driven,nonholonomic structured mobile robots are widely used in industries for automated work,inspection and explora-tion purposes.The trajectory tracking control of the four-wheel individual-d... Four-wheeled,individual-driven,nonholonomic structured mobile robots are widely used in industries for automated work,inspection and explora-tion purposes.The trajectory tracking control of the four-wheel individual-driven mobile robot is one of the most blooming research topics due to its nonholonomic structure.The wheel velocities are separately adjusted to follow the trajectory in the old-fashioned kinematic control of skid-steered mobile robots.However,there is no consideration for robot dynamics when using a kinematic controller that solely addresses the robot chassis’s motion.As a result,the mobile robot has lim-ited performance,such as chattering during curved movement.In this research work,a three-tiered adaptive robust control with fuzzy parameter estimation,including dynamic modeling,direct torque control and wheel slip control is pro-posed.Fuzzy logic-based parameter estimation is a valuable tool for adjusting adaptive robust controller(ARC)parameters and tracking the trajectories with less tracking error as well as high tracking accuracy.This research considers the O type and 8 type trajectories for performance analysis of the proposed novel control technique.Our suggested approach outperforms the existing control methods such as Fuzzy,proportional–integral–derivative(PID)and adaptive robust controller with discrete projection(ARC–DP).The experimental results show that the scheduled performance index decreases by 2.77%and 4.76%.All the experimen-tal simulations obviously proved that the proposed ARC-Fuzzy performed well in smooth groud surfaces compared to other approaches. 展开更多
关键词 Adaptive robust control coordinated control mobile robot fuzzy adaptation law fuzzy parameter adjustment direct torque allocation
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Inter-limb and intra-limb coordination control of quadruped robots 被引量:1
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作者 李华师 韩宝玲 罗庆生 《Journal of Beijing Institute of Technology》 EI CAS 2015年第4期478-486,共9页
To realize the coordinated and stable rhythmic motion of quadruped robots (QRs), the locomotion control method of QRs based on central pattern generator (CPG) was explored. In tradi- tional control strategies base... To realize the coordinated and stable rhythmic motion of quadruped robots (QRs), the locomotion control method of QRs based on central pattern generator (CPG) was explored. In tradi- tional control strategies based on CPG, few CPG models care about the intra-limb coordination of QRs, and the durations of stance phase and swing phase are always equal. In view of these deficien- cies, a new and simpler multi-joint coordinated control method for both inter-limb and intra-limb was proposed in this paper. A layered CPG control network to realize the locomotion control of QRs was constructed by using modified Hopf oscillators. The coupled relationships among hip joints of all limbs and between hip joint and knee joint within a limb were established. Using the co-simulation method of ADAMS and MATLAB/Simulink, various gait simulation experiments were carried out and the effectiveness of the designed control network was tested. Simulation results show that the pro- posed control method is effective for QRs and can meet the control requirements of QRs' gaits with different duty factors. 展开更多
关键词 quadruped robot locomotion control central pattern generator (CPG) inter-limb co-ordination intra-limb coordination Hopf oscillator
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A New Design of Robust H&infin;Load-Frequency Controller for Optimal Coordination of Energy Generation in Power System Stability Using LMI Approach 被引量:1
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作者 Chamni Jaipradidtham Chatchai U-thaiwasin 《Journal of Power and Energy Engineering》 2015年第4期146-154,共9页
This paper presents the problem of robust H&infin;?load frequency controller design and robust H¥ based approach called advanced frequency control (AFC). The objective is to split the task of balancing frequency ... This paper presents the problem of robust H&infin;?load frequency controller design and robust H¥ based approach called advanced frequency control (AFC). The objective is to split the task of balancing frequency deviations introduced by renewable energy source (RES) and load variations according to the capabilities of storage and generators. The problem we address is to design an output feedback controller such that, all admissible parameter uncertainties, the closed-loop system satisfies not only the prespecified H&infin;? norm constraint on the transfer function from the disturbance input to the system output. The conventional generators mainly balance the low-frequency components and load variations while the energy storage devices compensate the high- frequency components. In order to enable the controller design for storage devices located at buses with no generators, a model for the frequency at such a bus is developed. Then, AEC controllers are synthesized through decentralized static output feedback to reduce the complexity. The conditions for the existence of desired controllers are derived in terms of a linear matrix inequality (LMI) algorithm is improved. From the simulation results, the system responses with the proposed controller are the best transient responses. 展开更多
关键词 Optimal coordination ROBUST H∞ controller Load Frequency control LMI Approach
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Intelligent Sensing and Control of Road Construction Robot Scenes Based on Road Construction
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作者 Zhongping Chen Weigong Zhang 《Structural Durability & Health Monitoring》 EI 2024年第2期111-124,共14页
Automatic control technology is the basis of road robot improvement,according to the characteristics of construction equipment and functions,the research will be input type perception from positioning acquisition,real... Automatic control technology is the basis of road robot improvement,according to the characteristics of construction equipment and functions,the research will be input type perception from positioning acquisition,real-world monitoring,the process will use RTK-GNSS positional perception technology,by projecting the left side of the earth from Gauss-Krueger projection method,and then carry out the Cartesian conversion based on the characteristics of drawing;steering control system is the core of the electric drive unmanned module,on the basis of the analysis of the composition of the steering system of unmanned engineering vehicles,the steering system key components such as direction,torque sensor,drive motor and other models are established,the joint simulation model of unmanned engineering vehicles is established,the steering controller is designed using the PID method,the simulation results show that the control method can meet the construction path demand for automatic steering.The path planning will first formulate the construction area with preset values and realize the steering angle correction during driving by PID algorithm,and never realize the construction-based path planning,and the results show that the method can control the straight path within the error of 10 cm and the curve error within 20 cm.With the collaboration of various modules,the automatic construction simulation results of this robot show that the design path and control method is effective. 展开更多
关键词 Scene perception remote control technology cartesian coordinate system construction robot highway construction
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Multi-agent coordination strategy estimation method based on control domain
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作者 曙光 洪炳熔 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2001年第3期249-252,共4页
For estimation group competition and multiagent coordination strategy, this paper introduces a notion based on multiagent group. According to the control domain, it analyzes the multiagent strategy during competition ... For estimation group competition and multiagent coordination strategy, this paper introduces a notion based on multiagent group. According to the control domain, it analyzes the multiagent strategy during competition in the macroscopic. It has been adopted in robot soccer and result enunciates that our method does not depend on competition result. It can objectively quantitatively estimate coordination strategy. 展开更多
关键词 MULTIAGENT coordination control domain color histogram
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Improved Voltage Control Strategy for Photovoltaic Grid-Connected System Based on DoubleLayer Coordination Control 被引量:3
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作者 戚艳 贾宏杰 《Transactions of Tianjin University》 EI CAS 2012年第4期271-278,共8页
An improved automatic voltage coordination control strategy(AVCCS) based on automatic voltage control(AVC) and battery energy storage control(BESC) is proposed for photovoltaic grid-connected system(PVGS) to mitigate ... An improved automatic voltage coordination control strategy(AVCCS) based on automatic voltage control(AVC) and battery energy storage control(BESC) is proposed for photovoltaic grid-connected system(PVGS) to mitigate the voltage fluctuations caused by environmental disturbances.Only AVC is used when small environmental disturbances happen,while BESC is incorporated with AVC to restrain the voltage fluctuations when large disturbances happen.An adjustable parameter determining the allowed amplitudes of voltage fluctuations is introduced to realize the above switching process.A benchmark low voltage distribution system including PVGS is established by using the commercial software DIg SILENT.Simulation results show that the voltage under AVCCS satisfies the IEEE Standard 1547,and the installed battery capacity is also reduced.Meanwhile,the battery's service life is extended by avoiding frequent charges/discharges in the control process. 展开更多
关键词 协调控制策略 自动电压控制 低压配电系统 光伏并网 电压波动 IEEE标准 电池容量 环境干扰
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Coordination control for crankshaft forging hydraulic press 被引量:1
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作者 姚静 Li Yao +1 位作者 Cao Xiaoming Sha Tong 《High Technology Letters》 EI CAS 2019年第4期452-460,共9页
Taking a new type of full-fiber crankshaft forging hydraulic press as the research object,an upsetting-bending stroke coordination control is studied to improve crankshaft forming accuracy.A master-slave proportion in... Taking a new type of full-fiber crankshaft forging hydraulic press as the research object,an upsetting-bending stroke coordination control is studied to improve crankshaft forming accuracy.A master-slave proportion integration differentiation(PID)coordination control strategy based on velocity feed-forward is proposed to improve the coordination control accuracy.The structure and working process of the full-fiber crankshaft forging hydraulic press are introduced,and a mathematical model of the upsetting and bending control system are established.The coordination control strategy is verified experimentally.The experimental results show that the maximum tracking error of the coordination control strategy is reduced by 66%compared with the traditional PID controller,and the coordination motion accuracy is improved effectively. 展开更多
关键词 coordination SHAFT BENDING
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Optimal design of coordination control strategy for distributed generation system
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作者 王爱华 Norapon Kanjanapadit 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第1期51-56,共6页
This paper presents a novel design procedure for optimizing the power distribution strategy in distributed generation system. A coordinating controller, responsible to distribute the total load power request among mul... This paper presents a novel design procedure for optimizing the power distribution strategy in distributed generation system. A coordinating controller, responsible to distribute the total load power request among multiple DG units, is suggested based on the conception of hierarchical control structure in the dynamic system. The optimal control problem was formulated as a nonlinear optimization problem subject to set of constraints. The resulting problem was solved using the Kuhn-Tucker method. Computer simulation results demonstrate that the proposed method can provide better efficiency in terms of reducing total costs compared to existing methods. In addition, the proposed optimal load distribution strategy can be easily implemented in real-time thanks to the simplicity of closed-form solutions. 展开更多
关键词 分布式发电系统 优化设计 协调控制策略 非线性优化问题 最优控制问题 分配策略 负荷功率 协调控制器
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Bus coordination holding control for transit hubs under APTS
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作者 滕靖 赵明 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第1期131-137,共7页
To increase the passenger transferring efficiency, the bus coordination holding control for transit hubs, which is as an important dynamic dispatching method for improving the service level of transit hubs, was studie... To increase the passenger transferring efficiency, the bus coordination holding control for transit hubs, which is as an important dynamic dispatching method for improving the service level of transit hubs, was studied in the framework of bus coordination dispatching mode. Firstly, the bus coordination holding control flow was studied based on Advanced Public Transportation Systems (APTS) environment. Then a control model was presented to optimize the bus vehicle holding time, and a genetic algorithm was designed as the solving method. In the end, an example was given to illustrate the effectiveness of the control strategy and the algorithm. 展开更多
关键词 交通枢纽 APTS 协调控制 总线 公共交通系统 算法设计 传输效率 调度方法
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Angle Control of a Pneumatically Driven Musculoskeletal Model Based on Coordination of Agonist-Antagonist Muscle
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作者 Yuki Honda Fumio Miyazaki Atsushi Nishikawa 《Journal of Mechanics Engineering and Automation》 2012年第12期709-719,共11页
关键词 气动肌肉 骨骼模型 角度控制 拮抗 激动剂 气动执行器 关节模型 反馈控制系统
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Research on Distributed Coordination Control Method for Microgrid System Based on Finite-time Event-triggered Consensus Algorithm
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作者 Lizhen Wu Heng Yang +1 位作者 Jianping Wei Wendong Jiang 《Chinese Journal of Electrical Engineering》 EI CSCD 2024年第2期103-115,共13页
Microgrids are networked control systems with multiple distributed generators(DGs).Microgrids are associated with many problems,such as communication delays,high sampling rates,and frequent controller updates,which ma... Microgrids are networked control systems with multiple distributed generators(DGs).Microgrids are associated with many problems,such as communication delays,high sampling rates,and frequent controller updates,which make it challenging to realize coordination control among the DGs.Therefore,finite-time consensus algorithms and event-triggered control methods are combined to propose a distributed coordination control method for microgrid systems.The DG in the microgrid system serves as an agent node in the control network,and a distributed secondary controller is designed using finite-time consensus algorithm,such that the frequency and voltage restoration control has a faster convergence time and better anti-interference performance.The event-triggered function was designed based on the state information of the agents.The controller exchanges the state information at the trigger instants.System stability is analyzed using the Lyapunov stability theory,and it is verified that the controller cannot exhibit the Zeno phenomenon in the event-triggered process.A simulation platform was developed in Matlab/Simulink to verify that the proposed control method can effectively reduce the frequency of controller updates during communication delays and the burden on the communication network. 展开更多
关键词 MICROGRID event-triggered control distributed secondary control finite-time consensus algorithm coordination control
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Motion Planning Based Coordinated Control for Hydraulic Excavators 被引量:4
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作者 GAO Yingjie JIN Yanchao ZHANG Qin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第1期97-101,共5页
Hydraulic excavator is one type of the most widely applied construction equipment for various applications mainly because of its versatility and mobility. Among the tasks performed by a hydraulic excavator, repeatable... Hydraulic excavator is one type of the most widely applied construction equipment for various applications mainly because of its versatility and mobility. Among the tasks performed by a hydraulic excavator, repeatable level digging or flat surface finishing may take a large percentage. Using automated functions to perform such repeatable and tedious jobs will not only greatly increase the overall productivity but more importantly also improve the operation safety. For the purpose of investigating the technology without loss of generality, this research is conducted to create a coordinate control method for the boom, arm and bucket cylinders on a hydraulic excavator to perform accurate and effective works. On the basis of the kinematic analysis of the excavator linkage system, the tip trajectory of the end-effector can be determined in terms of three hydraulic cylinders coordinated motion with a visualized method. The coordination of those hydraulic cylinders is realized by controlling three electro-hydraulic proportional valves coordinately. Therefore, the complex control algorithm of a hydraulic excavator can be simplified into coordinated motion control of three individual systems. This coordinate control algorithm was validated on a wheeled hydraulic excavator, and the validation results indicated that this developed control method could satisfactorily accomplish the auto-digging function for level digging or flat surface finishing. 展开更多
关键词 hydraulic excavator motion planning coordinated control
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