76 research outputs found

    Dynamic Economic Dispatch of Wind Power Integrated System With Fully Developed Supply Responses of Thermal Units

    Get PDF
    已有文献分析了传统的离散时间调度模型,并指出这类调度模型存在备用容量上、下限不可达的问题。该文进一步指出这类调度模型中存在备用容量上、下限约束过; 于严格、限制机组的深度变负荷能力的不足。以连续时间调度模型为基础,建立了充分发挥机组深度变负荷能力的风火电联合随机调度模型。仿真实验结果表明,这; 种含风电场的电力系统动态经济调度模型能有效应对风电出力的随机波动性特征,充分发挥机组深度变负荷能力,在保证系统可靠性的前提下能节省更多的成本。Some researchers analyzed the traditional discrete-time scheduling; model, and pointed out that the upper and lower bounds of spinning; reserve offered by thermal units are unreachable. We further find that; the upper and lower bounds of spinning reserve modeled in the; discrete-time scheduling model are too strict in some situation. In; order to solve this problem, we analyzed the thermal units supply; responses based on the continuous time scheduling. And then a stochastic; scheduling model of wind & thermal power joint operation was established; in consideration of the thermal units supply responses. Simulation; results show the new model can effectively cope with random fluctuation; characteristics of wind power output, take full advantage of the supply; responses of thermal units, and save more cost while guaranteeing the; system reliability.国家自然科学基金项目; 福建省自然科学基金项

    Research Progress of Silicon-Based Spin Injection

    Get PDF
    自旋注入、自旋探测和自旋操控是构建半导体自旋电子器件的基础。在硅基材料上采用电的方式进行自旋注入,有利于自旋器件与微电子芯片的集成化,是当前该领域的研究热点课题之一。简要概述了硅基自旋注入的研究进展,首先介绍了半导体自旋注入的原理和方法,着重评述了以磁隧道结(MTJ)结构为核心的硅基自旋注入的研究进程,然后详细论述了硅基自旋注入的测试原理、器件结构和实验方法,最后给出了硅基自旋注入的主要研究目标和发展方向,并展望了硅基自旋电子器件的前景。The spin injection,spin detection and spin manipulation in semiconductor are the foundation for building spintronic devices.The silicon-based materials using electrical methods to spin injection can be beneficial to the integration of microelectronic chip with spintronic devices,and which is one of hot topics of research in this field.The research progress of the silicon-based spin injection is summarized briefly.The principle and method of the spin injection for semiconductors are introduced firstly.And then the research progress of silicon-based spin injection with magnetic tunnel junction( MTJ) as the core structure is reviewed.After that,the test principle,device structure and experimental method of silicon-based spin injection are discussed in detail.Finally,the main direction and research goal of silicon-based spin injection are pointed out,and the outlook of silicon-based spintronic devices is prospected.国家自然科学基金资助项目(61176092); 国家自然科学青年基金资助项目(11104232); 陇原青年创新人才扶持计

    Joint Optimization Scheduling ofWind-thermal Power System Considering Realizability

    No full text
    随着风电大规模地接入电力系统,目前迫切需要探索能够充分发挥风火发 电的互补机制与理论方法,以应对风电的随机性和不确定性。本文研究的主要 内容包括以下几个方面: 通过引入机会约束规划来处理风电的随机性,并建立了含概率约束的不确定模型。针对传统的离散时间调度模型中存在的能量不可交付和备用容量上下限不可达的问题,采用了含积分约束的连续时间调度模型,并最终将含概率约束的不确定非线性规划问题转化为一个确定性问题进行求解。 在此基础上进一步发现离散时间调度模型中除了存在备用上下限不可达的问题,同时也存在着备用容量上下限约束过于严格的问题,从而限制了机组的深度变负荷能力。针对这一问题,深入分析了机组...With large-scale wind power integrated into power system, we urgently need to explore and fully develop the complementary mechanism and theory method of wind thermal power generation to deal with the randomness and uncertainty of wind power. The major work of this paper includes the following parts: Through introducing chance constrained programming to cope with the randomness of wind power...学位:工程硕士院系专业:航空航天学院_工程硕士(控制工程)学号:2322013115336

    用高能量密度等离子体在室温下制备氮化钛薄膜

    No full text

    一种快速变温真空炉

    No full text
    一种快速变温真空炉,其主要包括炉管和加热炉,炉管分成高温区炉管、低温区炉管,高温区炉管与低温取炉管连接,实现在高温区炉管和低温区炉管快速移动的装置,其特征在于:快速移动装置是低温炉管外端设置有炉窗盖,炉窗盖布置有孔,拉杆与孔是动密封配合,使拉杆的里端与炉管里的承烧盒或承烧板直接或间接地连接固定;炉管布置有充气口和真空抽气口。优点在于设备简单,改造成本低,与为实现快速冷却,采用高温炉管水淬或油淬相比,大大延长了炉管的使用寿命,降低烧结成本,也更加实用

    一种同时提高热压磁环磁性能及力学性能的方法

    No full text
    一种同时提高热压磁环磁性能及力学性能的方法,包括将钕铁硼速凝片作为母合金快淬成的薄带,然后将薄带破碎磁选成均匀的快淬粉末,接着进行热压成型,热挤压成型,其特征在于在热压成型前将快淬粉末中均匀添加有纳米金属Cu粉末。与现有技术相比,本发明的优点在于:加入具有低熔点、延展性良好的纳米金属Cu粉末的目的是可以使具有该特点的纳米金属粉末在热压过程中,通过扩散的方式,更加均匀的分布在钕铁硼晶粒的晶界中,改善了磁体的织构,该晶界相化合物的维氏硬度远大于纯钕铁硼磁体晶界富钕相的维氏硬度,达到提高钕铁硼磁体力学性能的目的

    一种各向异性稀土永磁材料的再生方法

    No full text
    本发明公开了一种各向异性稀土永磁材料的再生方法,将各向异性近全密度的稀土永磁体的边角料和/或碎块进行预处理去除污物、油渍,再采用氢气处理并制造各向异性磁粉,并由各向异性磁粉添加非磁性成分的粘结剂,通过经过磁场取向成型制得粘结磁体。与现有技术相比,本发明的优点在于工序简单、生产效率高、能耗低,制得的磁粉及粘结磁体性能较佳

    热压过程对热变形钕铁硼磁体磁性能影响的研究

    No full text
    介绍了利用快淬粉制备全密度、高性能、各项异性钕铁硼稀土永磁体的有效方法-热压、热变形方法。成功制备出了磁能积巩。约3.44×10^5T-(A/m),剩磁所约1.352T,矫顽力Hcj约1×10^6A/m的热变形钕铁硼磁体。利用XRD、VSM、PPMS、SEM等材料表征手段对样品磁性能的各项异性以及取向度进行了分析,并讨论了工艺参数对样品磁性能的影响
    corecore