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基于Floquet理论的模块化多电平换流器小信号稳定性分析

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电力系统保护与控制 2021年第21期49卷 1-8页

作者：阮博郑雪朱蜀乐健国网湖北省电力公司经济技术研究院湖北武汉430077 武汉电力职业技术学院湖北武汉430079 武汉大学电气与自动化学院湖北武汉430072

为更好地描述模块化多电平换流器(Modular Multilevel Converter,MMC)中高次谐波动态的相互作用,基于线性时间周期(Linear Time-Periodic,LTP)系统理论对MMC进行建模,并基于Floquet理论进行MMC系统的小信号稳定性分析。首先通过MMC的桥... 详细信息

为更好地描述模块化多电平换流器(Modular Multilevel Converter,MMC)中高次谐波动态的相互作用,基于线性时间周期(Linear Time-Periodic,LTP)系统理论对MMC进行建模,并基于Floquet理论进行MMC系统的小信号稳定性分析。首先通过MMC的桥臂平均值模型建立系统的非线性时间周期系统模型,然后围绕周期轨道将该模型线性化得到MMC的LTP模型,最后通过针对LTP系统的Floquet理论分析MMC的小信号稳定性。分析结果表明:LTP模型可以准确描述MMC的小信号动态响应特性;Floquet分析可以精确刻画MMC参数构成的稳定边界。此外,所提模型和稳定性分析结果通过了基于MMC聚合模型的电磁暂态仿真和验证。

关键词：模块化多电平换流器线性时间周期小信号稳定性 Floquet理论次同步振荡

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2D阀控电液激振器偏置控制的特性分析

西安交通大学学报 2010年第9期44卷 82-86,127页

作者：任燕阮健贾文昂浙江工业大学机械制造及自动化教育部重点实验室杭州310014

为实现对液压缸活塞杆振动中心平衡位置偏置量的精确控制,提出2D阀与电液数字阀并联机构的新方案.在产生相同流量平均值的条件下,将并联机构等效为正开口滑阀,求解出振动中心的平衡位置,然后将并联数字阀等效为恒定负载,推导出偏置控制... 详细信息

为实现对液压缸活塞杆振动中心平衡位置偏置量的精确控制,提出2D阀与电液数字阀并联机构的新方案.在产生相同流量平均值的条件下,将并联机构等效为正开口滑阀,求解出振动中心的平衡位置,然后将并联数字阀等效为恒定负载,推导出偏置控制下振动波形的解析解.在5～200Hz范围内进行振动疲劳试验,试验结果表明:当2D阀阀开口一定时,并联数字阀阀口与活塞杆振动中心平衡位置点成线性关系,但偏置量不会大于最大振幅,振动波形类似正弦波;当并联数字阀阀口一定时,随2D阀阀口面积系数的增大,偏置的平衡位置点减小,振动的最大位置点呈先减小再增大的规律;当振动频率为200Hz、并联数字阀开口面积占最大并联阀阀口面积的25%时,振动的最大位置点在2D阀阀口面积的20%处最小.这一并联机构不仅能提高频响,保证电液激振器工作频率和激振幅值的分别控制,而且能够实现偏载量的独立、精确控制.

关键词： 2D阀偏置控制振动波形

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2D高速开关阀结构参数优化设计与实验

农业机械学报 2016年第11期47卷 391-398页

作者：贾文昂阮健李胜浙江工业大学机械制造及自动化教育部重点实验室杭州310014

对高速开关阀的结构参数进行优化设计,以提高其动态响应性能。主要从伺服螺旋机构导控面积的增大、旋转电磁铁转动惯量的降低和将传动机构设计成变传动比3方面进行结构优化和改进。提出斜槽型的阀芯结构以增大伺服螺旋导控级的面积梯度... 详细信息

对高速开关阀的结构参数进行优化设计,以提高其动态响应性能。主要从伺服螺旋机构导控面积的增大、旋转电磁铁转动惯量的降低和将传动机构设计成变传动比3方面进行结构优化和改进。提出斜槽型的阀芯结构以增大伺服螺旋导控级的面积梯度;为降低旋转电磁铁的转动惯量,提高其动态响应,引入6片26°均布结构的旋转电磁铁;为提高力矩输出,改善初始阶段的快速性,提出了变传动比的传动机构,并给出变传动比曲线和力矩变化曲线。在分析其工作原理和过程后建立旋转电磁铁、传动机构和伺服螺旋导控机构的数学模型;并在Matlab平台进行仿真分析,研究表明,结构优化后的开关阀幅频特性曲线在-3 d B下频率为240 Hz左右;最后建立2D高速开关阀的实验装置,通过满量程阶跃响应和零位泄漏率对仿真结果进行实验研究。在工作压力14、21 MPa下,阶跃响应时间分别为8.9、8.0 ms,零位泄漏分别为4.7、5.6 L/min。

关键词：高速开关阀传动机构快速响应优化设计

Eu^(3+)离子激活荧光粉Ca_(1.9)Eu_(0.1)NaMg_(2-x)Zn_x(VO_4)_3(0≤x≤1)的发光性质

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发光学报 2017年第8期38卷 995-1002页

作者：阮威威刘志国刘成振阮健韩建军赵修建硅酸盐建筑材料国家重点实验室武汉理工大学湖北武汉430070

采用固相反应法合成了Eu^(3+)离子激活的Ca_(1.9)Eu_(0.1)NaMg_(2-x)Zn_x(VO_4)_3(0≤x≤1),并研究了其发光和热猝灭性能。经粉末X射线衍射确认,反应产物由目标相和微量杂质相EuVO_4构成。在355 nm激发下,样品中均能同时观察到来自[VO_4... 详细信息

采用固相反应法合成了Eu^(3+)离子激活的Ca_(1.9)Eu_(0.1)NaMg_(2-x)Zn_x(VO_4)_3(0≤x≤1),并研究了其发光和热猝灭性能。经粉末X射线衍射确认,反应产物由目标相和微量杂质相EuVO_4构成。在355 nm激发下,样品中均能同时观察到来自[VO_4]_3-基团和Eu^(3+)离子的特征发光。研究结果表明:随着x值的增加,上述两种发光的强度均先增加后降低;而它们的最强激发峰位置由347 nm逐渐地红移至356 nm,Stokes位移也逐渐地减小。这种现象应归因于Zn3d轨道和O2p轨道间很强的轨道杂化效应,这种效应随着x值的增加而逐渐增强。此外,Eu^(3+)离子荧光发射强度最大值对应的x值与自激活荧光的不同。当x=1.0时,两者的相对强度差别最大。经荧光热猝灭测试确认,上述现象是由样品中的自激活荧光表现出比Eu^(3+)离子荧光更严重的荧光热猝灭造成的。因而,在紫外光激发下,样品发出荧光的颜色具有温度敏感性。

关键词：荧光粉碱土钒酸盐自激活荧光 Eu3+离子荧光热猝灭

Versatile application of wet-oxidation for ambient CO abatement over Fe(OH)_x supported subnanometer platinum group metal catalysts

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Chinese Journal of Catalysis 2020年第4期41卷 613-621页

作者： Hongling Guan Yang Chen Chongyan ruan jian Lin Yang Su Xiaodong Wang Lingbo Qu School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001HenanChina CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina College of Chemistry Zhengzhou UniversityZhengzhou 450001HenanChina

The efficient and stable abatement of CO pollutant under ambient conditions is of great significance;however,it remains a formidable ***,we report the versatile application of wet oxidation over Fe(OH)x supported subnanometer Pt group metal(PGM)catalysts for the complete removal of CO under ambient temperature and humidity ***,the 1.8 wt%Rh/Fe(OH)x catalyst exhibited better durability during a^1400 min run for wet oxidation than for dry CO *** characterization results including HR-TEM,H2-TPR,and in-situ DRIFTS suggested that Fe(OH)x,with good reducibility,promoted by the subnanometer Rh clusters,provided sites for the adsorption and reaction of O2 and H2 O to form OH ***,these OH species reacted with the adsorbed CO on Rh sites with a considerably lower activation energy(9 kJ mol^-1)than that of dissociated 0 species(22 kJ mol^-1),thus rationalizing the outstanding performance of Rh/Fe(OH)x for wet *** experiments with other PGMs revealed a good generality for the application of wet oxidation in the efficient abatement of CO under humid conditions with Fe(OH)x as the support.

关键词： Platinum group metals CO Oxidation Ambient condition Fe(OH)x Subnanometer clusters

Analysis of Accuracy of a High-speed Mobile Platform Control System

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厦门大学学报（自然科学版） 2002年第S1期41卷 38-39页

作者： ruan jian, YUAN Ju-long, ZHANG Li-bin, JI Shi-ming, LI Sheng (College of Mechanical & Electrical Engineering, Zhejinag University of Technology, Hangzhou 310014, China)

The efficient manufacture technique involves a high-speed control of platform mobile system. A linear acutor is presented in this paper. The linear acutor is constructed as a linear stepper motor. However, to sustain both high accuracy and high speed for the position and speed control, A single-stack computer system is constructed and a special control algorithm is prescribed to controled the linear actuator continuously. In this paper, the nonlinear errors resulted from the magnetic saturation and the hysteresis is anaysis and discussed. In the view of electromagnetic propotional control, the actuator is a stage proportional magnet, because the driving current to the linear acuator changes for a number of cycles and a series of reset points will occur as the current undergoes cyclic changes. At each reset point the original starting characteristics of the system are re-established. A large number of reset points across the full stroke of the platform results in a significant reduction in the nonlinear behavior. The stage control is first discussed. Experiments carried out to obtain the characteristics of the mobile platform control system. It is demonstrated that with the introduction of stage control, nonlinearities, such as saturation and hysteresis, are greatly reduced, system stiffness is increased, and the positioning accuracy and resolution are improved. The effect of dither due to a "digital fragment" signal is also examined and found to be crucial in reducing the hysteresis and in improving the resolution accuracy.

关键词： high-speed control mobile platform nonlinearities

组合人工湿地系统对污水处理厂二级出水的深度处理效果

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环境科学研究 2018年第12期31卷 2028-2036页

作者：祝志超缪恒锋崔健黄振兴阮文权江南大学环境与土木工程学院江苏无锡214122 江苏省厌氧生物技术重点实验室江苏无锡214122

为了解组合人工湿地系统深度处理污水的效果,利用水质分析和微生物多样性分析相结合的方法,研究了VF-HF组合人工湿地系统[由VFCW(垂直流人工湿地)与HFCW(水平流人工湿地)串联组成]深度处理污水处理厂二级出水的效果.结果表明:(1)稳定运... 详细信息

为了解组合人工湿地系统深度处理污水的效果,利用水质分析和微生物多样性分析相结合的方法,研究了VF-HF组合人工湿地系统[由VFCW(垂直流人工湿地)与HFCW(水平流人工湿地)串联组成]深度处理污水处理厂二级出水的效果.结果表明:(1)稳定运行期间,VF-HF组合人工湿地系统出水的ρ(CODCr)、ρ(NH4+-N)、ρ(TN)和ρ(TP)的平均值分别为18. 11、0. 41、0. 96和0. 16 mg/L,对CODCr、NH4+-N、TN和TP的平均去除率分别为67. 21%、89. 83%、90. 08%和70. 91%,且VFCW对CODCr的去除性能好于HFCW,HFCW对氮的去除性能好于VFCW.(2)VF-HF组合人工湿地系统中细菌的丰富度和多样性差异明显,VFCW和HFCW中上层填料中细菌的丰富度和多样性均大于下层,且系统中优势细菌富集明显,其中VFCW沸石层富集了优势反硝化细菌菌科(Comamonadaceae)和优势菌属(Desulfomicrobium),HFCW的石英砂层富集了优势反硝化细菌菌科(Xanthomonadaceae)和优势菌属(Silanimonas),HFCW的沸石层富集了优势反硝化细菌菌科(Rhodocyclaceae).研究显示,VF-HF组合人工湿地系统深度处理二级出水的效果较好,出水水质达到GB 3938—2002《地表水环境质量标准》Ⅲ类水质要求,且系统中富集了优势反硝化细菌菌科(Comamonadaceae,Xanthomonadaceae,Rhodocyclacea)以及优势菌属(Desulfomicrobium,Silanimonas).

关键词：人工湿地深度处理反硝化细菌

Modelling and Identification of a Digital Feed Drive

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厦门大学学报（自然科学版） 2002年第S1期41卷 21-22页

作者： LI Sheng, ruan jian, YUAN Ju-long, ZHANG Li-bin, JI Shi-ming (College of Mechanical & Electrical Engineering, Zhejinag University of Technology, Hangzhou 310014, China)

In many cases, the cutting method is usually adopted for the efficient machining of non-circular body of revolution and a feed drive is needed to actuate the cutting tool to and fro according to input signal wave. The feed drive for the purpose is required of fast response and accurate positioning. Both of these are highly dependent upon the actuating elements. Several schemes of actuation are specially interested. One is the introduction of piezoelectric actuation. However, the tiny working stroke of the piezoelectric material limits its application to a narrow range. Another is the application of electro-magnetic actuator. An innovative feed drive actuated by the stepper motor is introduced for the purpose. For a conventional step operating mode, a stepper motor can only be controlled to position at finite discrete points. Thus, when it is applied as an actuator of the feed drive, it is very difficult to maintain high accuracy and fast response. To eliminate quantitative error, the stepper motor is controlled under the continual mode. It is achieved with a micro-controller system and a built-in control algorithm program, called "tracking algorithm". Within each sampling cycle, the micro-controller will sample the input signal and the time interval will be divided into two parts according to the relative position between two adjacent stepping points. The phase coils correspondent to the two adjacent stepping points are energized respectively with calculated time duration. In the way, the motion of the tool frame smoothly tracks the input signal. This paper presents modeling and identification of frequency response of the proposed drive. The dynamic response of the feed drive is manly decided by the natural frequency of the stepper motor. For the conventional small-size stepper motors, the natural frequency is within the range 200～400 Hz. Experimental results show that the stepper motor actuated tool frame can smoothly keep in track of the input signal wave under "t

关键词： feed drive digital control frequency response identification

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基于FPGA的数字保护中卡尔曼滤波的实现

电力系统保护与控制 2009年第22期37卷 121-125页

作者：阮建国陈炯华东理工大学上海200237

卡尔曼滤波算法具有收敛速度快、收敛精度高等优点,但由于卡尔曼滤波算法不仅包含矩阵的连乘,而且还有矩阵的求逆运算和迭代算法,这使得卡尔曼滤波算法难以在MCU和DSP这类数字平台上实时地高速实现。介绍了一种基于FPGA的卡尔曼滤波算... 详细信息

卡尔曼滤波算法具有收敛速度快、收敛精度高等优点,但由于卡尔曼滤波算法不仅包含矩阵的连乘,而且还有矩阵的求逆运算和迭代算法,这使得卡尔曼滤波算法难以在MCU和DSP这类数字平台上实时地高速实现。介绍了一种基于FPGA的卡尔曼滤波算法的实现方法,该方法针对数字保护中卡尔曼滤波算法的特点,结合FPGA的结构特性,对算法的结构进行适当的改进和变换,避开难以实现的矩阵求逆运算和运算量巨大的矩阵连乘运算,大大简化了迭代的过程。在此基础上,利用FPGA的高速性和灵活性实现了基于硬件逻辑的卡尔曼滤波。

关键词：卡尔曼滤波数字保护 FPGA 基波分量状态机