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排序方式: 共有932条查询结果,搜索用时 140 毫秒
31.
设计并实现了一个小型风力发电机的外特性测试平台,平台包括低速开放式风洞、数据采集系统两部分.风洞设计成口径3.5 m的直流式风洞,实验段采用圆形截面,动力段采用多风机提供动力,在风流通过蜂窝器后,大大改善了风流效果并提高了可靠性.数据采集系统通过工业控制数据采集卡对风速、风力发电机转速、输出电压、电流等进行数据采集和处理.通过对某小型风力发电机进行测试的结果表明,平台可满足测试小型风机外特性的实验要求. 相似文献
32.
在电子信息专业的操作系统课程实验教学中提出并实践了一系列教改措施.编写了具有电子信息类特色的实验教材;突出了“原理—实例一实践”的具有专业特色的课堂教学与实验教学相结合新模式;实验内容具有信息与通信工程专业、电子科学技术、自动化专业和信息安全专业的特色.实践了“突出重点—因材施教—重点研讨—评析总结”4个环节构成的新型实验教学方法. 相似文献
33.
从设计、数学建模、仿真等方面研究了微电网仿真与实验系统,在微电网模型基础上,采用美国西部联合电网(Western Systems Coordinating Council,WSCC)3机9节点系统作为标准输电网模型,结合硬件仿真实验平台,开发出微电网仿真与实验系统。该系统包括风力发电系统、光伏发电系统、并网接入系统、模拟输配电系统、负荷和仿真实验平台。研制的仿真及实验系统能够稳定可靠运行,实验证实了模型的正确性。应用表明,系统设计合理、功能完善,各方面性能能够满足微电网仿真和实验的要求。 相似文献
34.
LabVIEW在运动控制系统实验平台的应用和实现 总被引:1,自引:0,他引:1
运动控制系统实验平台即要求高速的信号处理能力,强大的组网能力,又要求有可视化的控制视图。为了将LabVIEW引入到现有运动控制实验教学中,改造的平台采用LabVIEW开发平台设计上位机的人机交互界面以取代传统实验平台的触控屏,下位机的通信程序以及工艺程序则通过Twidosoft编程软件实现。PC机与PLC的通信基于Modbus串行总线;PLC与伺服驱动器的通信基于CANopen总线,整个运动控制系统实验平台为"PC+PLC+伺服驱动器"的结构模式。LabVIEW在运动控制系统平台的引入,可以方便地实现数据采集和监视控制功能,直观且逼真地显示伺服电机的控制,较好地提高了原有实验平台的功能扩展性。 相似文献
35.
文中基于美国西部联合电网(Western Systems Coordinating Council,WSCC)3机9节点系统,建立了1个带有逆变并网接口的输电网模型,并利用逆变并网接口模型模拟了微电网与上级输电网的连接,对微电网对上级电网电压与频率的支持情况进行了数字仿真。仿真结果表明在上级输电网的有功与无功负荷发生突变时,微电网的接入使上级输电系统的有功与无功功率能够实现就地平衡,并保持系统频率与电压幅值的稳定。整个微电网系统仿真环境设定均按照实验室所能达到的低电压低容量条件下完成。文中所有仿真算法及结果均在PSCAD/EMTDC软件环境及动态模拟实验室中得到验证。 相似文献
36.
Compacted graphite cast iron (CGI) has been the material for high-power diesel engines recently, but its increased strength causes poor machinability. In this study, coated and uncoated carbide tools were used in dry milling experiment and FEM simulation to study the machinability of CGI and wear behaviour of tools. The experimental and FEM simulation results show that coated tool has great advantage in dry milling of CGI. SEM and EDS analysis of tool wear indicate the wear morphology and wear mechanism. Adhesive wear is the main mechanism to cause un-coated tool wear, while abrasive wear and delamination wear are the main mechanism to cause coated tool wear. Stress and temperature distribution in FEM simulation help to understand the wear mechanism including the reason for coating peeled off. 相似文献
37.
为进一步实现CUBA与CBA联赛新时期改革计划,疏通我国篮球后备人才战略培养路径,以“新时期”CUBA与CBA的人才衔接与培育为研究对象,运用文献资料、录像观察、数理统计等方法,对CBA联赛选秀球员进行综合分析。研究结果表明:1)存在问题包括组织机构衔接不畅、选秀球员竞技水平不精、人才培养观契合度不高及俱乐部注意程度不足4个方面。2)改善路径包括逐渐推进多元主体衔接度及流畅性、全面优化高校球员竞技能力及水平、消除人才培养僵化及保守化、扎实提升俱乐部关注程度及积极性。 相似文献
38.
《Journal of The Franklin Institute》2023,360(13):9637-9662
This paper addresses the distributed control of delayed interconnected nonlinear systems with time-varying delays in both the local subsystems’ dynamics and the physical interconnections among the subsystems. The Takagi–Sugeno fuzzy model with nonlinear consequent parts (N-TS), which is capable to provide less complex representations than standard T–S fuzzy models, is considered to efficiently deal with this class of complex systems. Then, based on Lyapunov–Krasovskii stability arguments, a synthesis condition is proposed to design a distributed control law such that the origin of the closed-loop interconnected system is locally asymptotically stable together with a guaranteed set of admissible initial conditions for which the validity of the N-TS fuzzy model is ensured. Moreover, a quasi-convex optimization procedure is formulated to enlarge the set of admissible initial conditions. The effectiveness of the proposed synthesis condition is validated in two numerical examples, including an interconnected power network with seven generators. 相似文献
39.
《Journal of The Franklin Institute》2023,360(13):9579-9601
The current parking trajectory planning algorithms based on geometric connections or formulation of optimization problems in automatic parking systems have strict requirements on the starting position, lower planning efficiency and discontinuous curvature of the reference trajectory. In order to solve these problems, a hierarchical planning algorithm which is combined with nonlinear optimization and the improved RRT* algorithm (Rapidly-exploring Random Tree Star) with Reeds-Shepp curve is proposed in this paper. First, the improved RRT*RS algorithm with the rapid repulsion-straddle experiment is designed for enhancing the efficiency of path planning. Second, because of the shortcomings of the Reeds-Shepp curve that can meet the minimum turning radius but not realize the continuous curvature of the path, a nonlinear optimization problem based on convex-set obstacle constraints is formulated and solved. Finally, simulation results show that the proposed parking trajectory planning algorithm in this paper can plan an effective parking trajectory with continuous curvature in different starting positions and multiple parking scenarios. 相似文献
40.
《Journal of The Franklin Institute》2023,360(9):5929-5946
Sylvester quaternion tensor equations have a wide range of applications in image processing and system and control theory. In this paper, by the Kronecker product and vectorization operator and the properties of quaternion tensors, we focus mainly on proposing the tensor form of the generalized product-type biconjugate gradient method for solving generalized Sylvester quaternion tensor equations. As an application, we apply the proposed method to restore a blurred and noisy-free color video. The obtained numerical results illustrate the effectiveness of our method compared with some existing methods. 相似文献