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基于改进灰狼优化算法的有源配电网重构方法

河北电力技术 2024年第4期43卷 10-14,79页

作者：姚琦黎曜刘闯国网湖北省电力有限公司荆门供电公司湖北荆门448000

为了提高有源配电网系统运行的经济性和稳定性,提出了一种基于改进灰狼算法的有源配电网重构方法。以配电网系统网损最小和电压偏移最小为目标函数建立有源配电网重构模型,并将多目标转化为单目标进行求解。采用Tent混沌映射、收敛系数... 详细信息

为了提高有源配电网系统运行的经济性和稳定性,提出了一种基于改进灰狼算法的有源配电网重构方法。以配电网系统网损最小和电压偏移最小为目标函数建立有源配电网重构模型,并将多目标转化为单目标进行求解。采用Tent混沌映射、收敛系数指数调整和自适应位移等策略对灰狼优化算法进行改进,使IGWO算法的寻优能力得到显著提升。利用改进IEEE33节点系统进行仿真测试,并将IGWO算法的重构效果与GWO算法和PSO算法进行对比,结果表明,采用IGWO算法重构后的最低网损和最小电压偏移分别为54.89kW和0.00772,两项指标均优于GWO算法和PSO算法,验证了所提有源配电网重构方法的实用性和优越性。

关键词：有源配电网重构改进灰狼优化算法综合目标分布式电源

航天器多级自由边界模拟系统姿态平衡协调控制

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航天器环境工程 2024年第1期41卷 101-108页

作者：张大志骆巍刘闯朱万铖北京科技大学机械工程学院北京100083 北京卫星环境工程研究所北京100094

为了消除天地力学环境不一致对航天器在轨运行精度的影响,需要在地面开展航天器在轨微振动环境模拟试验,因此针对航天器的设施部分和平台部分,在航天器上、下两端建立了自由边界模拟系统和自动控制模块,通过力闭环和位移闭环对航天器重... 详细信息

为了消除天地力学环境不一致对航天器在轨运行精度的影响,需要在地面开展航天器在轨微振动环境模拟试验,因此针对航天器的设施部分和平台部分,在航天器上、下两端建立了自由边界模拟系统和自动控制模块,通过力闭环和位移闭环对航天器重力卸载过程的平衡协调控制算法进行了设计和实施;并通过硬件设施搭建和软件程序编写完成现场试验,验证了控制系统的可行性和稳定性,也为未来航天器地面模拟试验中重力卸载过程控制系统的设计提供技术支撑并积累了工程经验。

关键词：航天器自由边界模拟自动闭环控制姿态平衡协调控制

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抽水蓄能电站下水库进/出水口附近区域水流汇聚和分散特性研究

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水电能源科学 2024年第10期42卷 176-180,195页

作者：任在民鞠彬孙田田刘创中国电建集团华东勘测设计研究院有限公司浙江杭州311122 中水北方勘测设计研究有限责任公司天津300222 武汉大学水资源工程与调度全国重点实验室湖北武汉430072

研究抽水蓄能电站进/出水口区域的水动力特性,对保障电站取水防沙以及安全运行具有指导意义。采用平面二维非恒定流水动力数学模型,对MQ抽水蓄能电站下水库进/出水口水动力特性开展数值模拟研究。结果表明,抽水过程中进/出水口上游“汇... 详细信息

研究抽水蓄能电站进/出水口区域的水动力特性,对保障电站取水防沙以及安全运行具有指导意义。采用平面二维非恒定流水动力数学模型,对MQ抽水蓄能电站下水库进/出水口水动力特性开展数值模拟研究。结果表明,抽水过程中进/出水口上游“汇聚”效应、放水发电过程中向进/出水口上游“分散”效应均逐渐减小,下游均逐渐增加;抽水工况下,进/出水口附近水域流态整体平顺,对岸出现环流,并逐渐扩散移动至上游;放水发电工况下,进/出水口放水水流两侧形成环流,上游侧环流在放水发电过程中向对岸移动,并向上游扩散,下游侧环流在放水过程中向下游扩散;河段内放水发电工况流态较抽水工况更为复杂,环流的数量、尺度均大于抽水工况。结果可为电站取水防沙及水工设计提供依据,并可为其他类型抽水蓄能电站建设提供参考。

关键词：抽水蓄能电站进/出水口汇聚分散数学模型

面向东北电网调峰辅助服务市场交易主体的分摊上限动态机制设计

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电力自动化设备 2024年第3期44卷 142-149页

作者：王一帆王艺博尹立敏刘闯蔡国伟徐粤洋东北电力大学电气工程学院吉林吉林132012

东北电网现行的调峰辅助服务市场机制难以应对市场结构变化带来的交易主体实际调峰收益低于预期、积极性降低等问题,且难以满足未来我国以新能源为主体的新型电力系统发展需求。在介绍东北电网现行调峰辅助服务市场费用分摊机制的基础上... 详细信息

东北电网现行的调峰辅助服务市场机制难以应对市场结构变化带来的交易主体实际调峰收益低于预期、积极性降低等问题,且难以满足未来我国以新能源为主体的新型电力系统发展需求。在介绍东北电网现行调峰辅助服务市场费用分摊机制的基础上,分析其局限性,提出面向市场参与主体的分摊上限动态调整机制,以保障调峰供应方的调峰收益;构建以市场交易主体综合收益最高为目标的动态分摊上限数学模型,并提出用于评估调峰辅助服务市场的指标体系。基于辽宁省电网实际运营数据的算例结果验证了所提机制的合理性与有效性。

关键词：东北电网辅助服务分摊机制电力市场新能源消纳

起爆方式对椭圆截面战斗部破片速度分布的影响

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爆炸与冲击 2024年第10期44卷 98-112页

作者：邓宇轩张先锋刘闯李鹏程马正伟刘子涵南京理工大学机械工程学院

为研究椭圆截面战斗部在不同起爆方式下破片速度的分布特性，建立了5种具有不同短长轴比的椭圆截面战斗部数值模拟模型。开展了端面中心单点、短(长)轴中点双点、短长轴中点4点以及端面面起爆5种起爆方式数值模拟研究，分析了不同起爆... 详细信息

为研究椭圆截面战斗部在不同起爆方式下破片速度的分布特性，建立了5种具有不同短长轴比的椭圆截面战斗部数值模拟模型。开展了端面中心单点、短(长)轴中点双点、短长轴中点4点以及端面面起爆5种起爆方式数值模拟研究，分析了不同起爆方式下椭圆截面战斗部破片的速度分布及能量输出特性。研究结果表明：在径向方向，战斗部在不同起爆方式下破片最大径向速度变化规律基本一致，均呈现由长轴至短轴方向对数增长，且随着短长轴比的增大，短长轴方向破片速度差值逐渐减小。然而，不同起爆方式下椭圆截面战斗部最大速度截面上破片速度平均值存在明显差异，具体表现为端面起爆时的破片径向平均速度最高，单点起爆最低，且随着起爆点数量的增加，最大速度截面上的破片的整体平均速度逐渐增大。在轴向方向，受端面稀疏波的影响，不同方位角最大破片速度均出现在靠近非起爆端1/4处，且起爆点在短轴轴线上相较于在长轴轴线上会提高靠近起爆端长轴方向的破片速度，但短轴方向沿轴向的破片速度分布无明显差异。此外，不同起爆方式对椭圆截面装药爆炸能量输出特性无明显影响，其中27%的装药能量转化为壳体动能，有50%的能量被壳体断裂变形以及空气冲击波消耗。

关键词：椭圆截面战斗部爆炸驱动破片速度起爆方式能量输出

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Numerical simulation study on the relationship between mining heights and shield resistance in longwall panel

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International Journal of Mining Science and Technology 2017年第2期27卷 293-297页

作者： liu chuang Li Huamin Jiang Dongjie School of Energy Science and Engineering Henan Polytechnic University School of Safety Science and Engineering Henan Institute of Engineering

A numerical model based on a Continuum-based Distinct Element Method(CDEM) was used to carry out a dynamic simulation of the interaction between shield and rock strata movement in longwall mining. In Northern China, the Ordos coal field geological conditions and operational characteristics were used as a case example. The CDEM was constructed on Ordos coal field shield's operation characteristics and geological conditions. Numerical modelling was carried out to investigate the effects of different mining heights on the caving process, movement characteristics, equilibrium and stability conditions of overburden as the interaction between shield and surrounding rocks. With the numerical model, the internal factors for changes in shield resistance under different mining heights was found. The quantitative relationship between mining heights and shield resistance was also obtained by the numerical simulation.

关键词： Numerical simulation Shield resistance Interaction between shield and surrounding rock Mining heights

Evolutionary algorithm based on dynamical structure of membrane systems in uncertain environments

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International Journal of Biomathematics 2016年第2期9卷 1-16页

作者： chuang liu Linan Fan School of Information Engineering Shenyang University Shenyang Liaoning 110044 P. R. China

In this paper, a new evolutionary algorithm based on a membrane system is proposed to solve the dynamic or uncertain optimization problems. The proposed algorithm employs objects, a dynamical membrane structure and several reaction rules of the membrane systems. The object represents a candidate solution of the optimization problems. The dynamical structure consists of the nested membranes where a skin membrane contains several membranes, which is useful for the proposed algorithm that finds optimal solutions. The reaction rules are designed to locate and track the optimal solutions of the dynamic optimization problems （DOPs）, which are inspired by processing the chemical compounds in the region of cellular membranes. Experimental study is conducted based on the moving peaks benchmark to evaluate the performance of the proposed algorithm in comparison with three state-of-the-art dynamic optimization algorithms. The results indicate the proposed algorithm is effective to solve the DOPs.

关键词： Membrane systems membrane algorithm dynamic optimization problems.

A progressive approach to predict shot peening process parameters for forming integral panel of Al7050-T7451

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Chinese Journal of Aeronautics 2021年第5期34卷 617-627页

作者： chuang liu Zhiyong ZHAO Xianjie ZHANG Junbiao WANG School of Mechanical Engineering Northwestern Poly technical UniversityXi'an 710072China

In this paper,a progressive approach to predict the multiple shot peening process parameters for complex integral panel is ***,the invariable parameters in the forming process including shot size,mass flow,peening distance and peening angle are determined according to the empirical and machine ***,the optimal value of air pressure for the whole shot peening is selected by the experimental ***,the feeding speed for every shot peening path is predicted by regression *** integral panel part with thickness from 2 mm to 5 mm and curvature radius from 3200 mm to 16000 mm is taken as a research object,and four experiments are *** order to design specimens for acquiring the forming data,one experiment is conducted to compare the curvature radius of the plate and stringer-structural specimens,which were peened along the middle of the two *** most striking finding of this experiment is that the outer shape error range is below 3.9%,so the plate specimens can be used in predicting feeding speed of the integral *** second experiment is performed and results show that when the coverage reaches the limit of 80%,the minimum feeding speed is 50 mm/*** this feeding speed,the forming curvature radius of the specimens with different thickness from the third experiment is measured and compared with the research object,and the optimal air pressure is 0.15 ***,the plate specimens with thickness from 2 mm to 5 mm are peened in the fourth experiment,and the measured curvature radius data are used to calculate the feeding speed of different shot peening path by regressive analysis *** algorithm is validated by forming a test part and the average deviation is 0.496 *** is shown that the approach can realize the forming of the integral panel precisely.

关键词： Curvature radius measure Integral panel Process parameters prediction Regressive analysis method Shot peening process

Full-State-Constrained Non-Certainty-Equivalent Adaptive Control for Satellite Swarm Subject to Input Fault

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IEEE/CAA Journal of Automatica Sinica 2022年第3期9卷 482-495页

作者： Zhiwei Hao Xiaokui Yue Haowei Wen chuang liu National Key Laboratory of Aerospace Flight Dynamics School of AstronauticsNorthwestern Polytechnical UniversityXi’an 710072China IEEE

Satellite swarm coordinated flight(SSCF)technology has promising applications,but its complex nature poses significant challenges for control *** response,this paper proposes an easily solvable adaptive control scheme to achieve high-performance trajectory tracking of the SSCF system subject to actuator efficiency losses and external *** existing adaptive controllers based on the certaintyequivalent(CE)principle show unpredictability and nonconvergence in their online parameter *** overcome the above vulnerabilities and the difficulties caused by input failures of SSCF,this paper proposes an adaptive estimator based on scaling immersion and invariance(I&I),which reduces the computational complexity while improving the performance of the parameter ***,a barrier Lyapunov function(BLF)is applied to satisfy both the boundedness of the system states and the singularity avoidance of the *** is proved that the estimator error becomes sufficiently small to converge to a specified attractive invariant manifold and the closed-loop SSCF system can obtain asymptotic stability under full-state ***,numerical simulations are performed for comparison and analysis to verify the effectiveness and superiority of the proposed method.

关键词： Dynamic scaling full-state constraints input faulttolerance non-CE adaptive control satellite swarm