基于概率法的电力系统安全分析

为应对电力系统安全分析中的停机问题，基于概率法的方式，将常用的确定停机计算与加入了概率法的概率停机进行比较，研究了二者的区别与其在长期投资方向的不同。在进行电力系统停机分析时，通常会分别从确定停机与概率停机的角度出发，对其应急状态下的潮流进行计算。但前者的方法可能导致极低概率的停机事件被忽略，进而影响长期的资金投资。通过加入概率法的计算，使得对单个停机事件的判定由其具体的频率来确定，增加了系统运行的稳定性。     

Pressure-assisted direct bonding of copper to silicon nitride for high thermal conductivity and strong interfacial bonding strength

To achieve superior thermal and mechanical properties of copper-bonded (Cu-bonded) Si₃N₄ substrate, a pressure-assisted direct bonded Cu (DBC) technique was applied to bond Cu foil with Si₃N₄ plate. The effects of oxide layer (SiO₂) thickness of Si₃N₄ plate on the microstructure, thermal and mechanical properties of the Si₃N₄-DBC samples were investigated. The successful bonding of Cu foil to Si₃N₄ plate was confirmed by the presence of the interfacial products of Cu₂MgSiO₄ and CuYO₂. Additionally, it was demonstrated that a thin SiO₂ layer can result in a discontinuous distribution of interfacial products while a thick one can lead to the formation of pores in SiO₂ layer. Notably, the sample prepared by Si₃N₄ plate with 5-μm-thickness SiO₂ layer and Cu foil with 5.9-μm-thickness oxide layer (Cu₂O) exhibited the optimally comprehensive properties with thermal conductivity of 92 W·m^?1·K^?1 and shearing strength of 102 MPa, which demonstrates significant promise for application in power electronic modules.

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航空影像处理与应用

简述航空影像数据的获取手段,针对不同的影像产品通过不同的处理方法来获取相应的数字产品,并简述了这些数字产品在城市规划建设中的应用。     

环氧地坪一次成活施工技术

环氧地坪较之水磨石、地面砖等有许多优点,文章详细介绍了某工业厂房的环氧地坪施工,供国内同行借鉴。     

全站仪电子记录方案设计与实现

提出了用于全站仪电子记录的设计方案,介绍了程序设计主要过程及其功能,分析了本方案的优点,并对相关问题进行说明.     

基于SiPLS和SPA波长选择的玉米组分测量研究

研究分析80个玉米实验光谱数据,经预处理后,分别进行区间偏最小二乘(iPLS)、组合区间偏最小二乘法(SiPLS)和连续投影算法(SPA)优选玉米水分组分的最佳波长,建立校正模型。结果表明,iPLS、SiPLS和SPA将建模变量从700个分别降低到70、140和2个,各占据全光谱的10%、20%和0.29%,而其建模精度比700个全谱变量建模精度甚至更好。其中SiPLS和SPA的建模精度相当,但是SPA方法将建模变量从700个降低到2个,计算复杂度得到最大程度的降低,并保持了建模精度,表明SPA是一种有效的特征波长提取方法,且这一研究方法可推广应用到对玉米中油脂、蛋白质和淀粉的含量检测中。     

电力波分复用网络中基于软管模型的生存性设计

生存性设计是规划电力通信波分复用(WDM)网络时必须考虑的问题。传统的方法根据各节点对的峰值速率来制定保护规划方案,也并未考虑光纤链路之间共享物理资源的情况,既不准确又浪费资源。为解决上述问题,提出了一种新的计算共享风险链路组的失效概率模型,并以此为基础,提出了基于软管不确定业务量模型和共享风险链路组的分级保护算法——HSP算法,并通过计算机仿真对该算法的性能进行了评估。结果表明,HSP显著提高了找到保护路径的可能性,从而降低了受损业务无法恢复的概率。失效概率模型和HSP算法还应用到了某省级电力波分复用核心网络的成效评估和规划设计中,作为评估该省电力骨干光传输网络建设成本和可靠性的依据。     

Stochastic frequency-security constrained energy and reserve management of an inverter interfaced islanded microgrid considering demand response programs

This paper addresses a novel security constrained energy management system of a microgrid which considers the steady-state frequency. Microgrid frequency as a key control variable, continuously exposes to be excursed of its nominal value due to unpredictable intermittencies arise from renewable sources and/or load consumptions. Moreover, great utilization of inertia-less inverter-interfaced distributed energy resources intensifies potential frequency excursions. As a result, energy and reserve resources of a microgrid should be managed such that the microgrid frequency lies within secure margins. To that end, a new objective function on the basis of the frequency dependent behavior of droop-controlled distributed generations is formulated using a mixed integer linear programming. It is aimed to optimize the microgrid frequency according to the economic and environmental policies. Besides, to seek the active participation of the consumers into proposed frequency management approach, a linearized ancillary service demand response program is also proposed. In addition, to properly model the impacts of microgrid various uncertainties in the frequency management approach, a two-stage stochastic optimization algorithm is employed. Simulations are performed in a typical microgrid which operates in the islanded mode during a 24 h scheduling time horizon. The numerical results show the impressiveness of the proposed frequency aware energy management system while concurrently managing the microgrid security and economical aspects. Furthermore, it is demonstrated that utilization of demand response programs economizes the microgrid frequency management approach.