查询词典 transient stability

In terms of each of these essentials, Lyapunov direct methods, transient energy function methods and extended equal-area criterion are critically compared in this four-part paper. This reveals the essence causes for why both Lyapunov direct methods and TEF methods cannot be applied to transient stability analysis of power systems.

由4篇短文组成的系列文章按照上述各要素，讨论了针对平衡点稳定性的李雅普诺夫法、将平衡点稳定性理论应用于有界稳定性的暂态能量函数法以及针对有界稳定性的扩展等面积准则这3种稳定性理论在大扰动稳定性分析中的应用。

ABSTRACT Power system transient stability analysis and its preventive control are key to power system transient security analysis and contr...

电力系统暂态稳定分析及其预防控制是电力系统暂态安全分析和控制的核心内容，它直接关系到对电力系统运行的基本要求——安全、优质、经济。

The some basic methods in composite mechanics are introduced,and relative formulations are derived.Maximum stress criterion,Maximum strain criterion,Hill criterion and Cai-Wu criterion are showed.The solid model of level-stability-panel is built by CATIA software,its finite element model by PATRAN/NASTRAN software.Through finite element analysis,the stresses and displacements of level-stability-panel are obtained.In order to analyze the strength of asingle part of level-stability-panel,the software CLOP is developed.The process of taking the data from NASTRAN's results and importing them to CLOP is showed.The strength of back wall of lev el-stability-panel is calculated by CLOP.

论文叙述了复合材料力学分析的基本方法，并推导了相应的计算公式，给出了几种常用的强度准则；利用CATIA软件对某型直升机的平尾进行实体建模，然后在PATRAN/NASTRAN软件中读入该模型，形成了有限元分析模型，并进行有限元分析，获得了平尾的应力云图和位移云图；为了对平尾的局部复合材料结构进行强度分析，开发了CLOP程序；从平尾结构中取出后樯作为强度分析的对象，表示了从NASTRAN分析的结果到CLOP程序输入的方法，计算出了后樯的强度数据。

In order to study the stability of non-Newtonian fluid and its flow pattern discrimination method,the integral stability theory and local stability theory are applied to the concentric annulus flowing of plastic fluid and power-law fluid,then a relevant stability parameter expression of discriminating flow pattern is derived and set up in the paper.

针对非牛顿流体的稳定性问题及其流态判别的研究，将整体稳定性理论及局部稳定性理论应用于塑性流体和幂律流体在同心环空的流动中，建立和推导出相对应的判别流动状态的稳定性参数表达式。这些参数的临界值与牛顿液体流态准数雷诺数的临界值，同样具有与液体流变性无关的特点。

The relationship between minimal model characteristic value of electric power system tie flow Jacobin matrix and voltage steady-state stability is was discussed, and the minimal model eigenvalue is was defined as voltage stability abundant degree. On this foundation, the sensitivity of voltage stability abundant degree to control variables and to PQ point load are was defined in order to seek the factors of impacting voltage stability and explore the voltage weak point, and give out their algorithm simultaneously.

讨论了电力系统潮流雅可比矩阵最小模特征值与系统电压静态稳定性的关系，将最小模特征值定义为电压稳定裕度，在此基础上定义了电压稳定裕度对控制变量的灵敏度和PQ节点负荷灵敏度，用以找出对系统电压稳定性造成影响的因素和寻找系统电压薄弱点，同时给出了它们的算法。

By using the optimal power flow,the relation between the electricity purchasing cost change and the line stability limit which is the product of the stability limit factor and the basic stability limit of the line,is described by the derivative of the augmented lagrangian function with respect to the line stability limit factor.

以最优潮流为工具，将线路的稳定限额看作是基准传输容量限值与稳定限额因子的乘积，通过增广拉格朗日函数对线路稳定限额因子的导数描述了系统购电成本的变化与线路稳定限额因子和线路基准稳定限额乘积的关系。

The results show that the atmosphere has a big influence on the thermal stability of C_(60).C_(60) begins to decompose at 423.5℃in the air,the deomposed peak temperature is 668.5℃,but very stable in the helium atmosphere,only sublimate,the crystal shape of C_(60) has a certain influence to its thermal stability.The synthesized nine kinds of nitro-fullerene derivatives all have good thermal stability and their decomposed peak temperatures all exceed 350℃.The thermal explosion temperature for 5 seconds delay of product 4 is 253℃.The category,number and position of nitryl group in nitro-fullerene derivatives all have influence on their thermal stability.

利用差热分析仪和DSC-TG综合热分析仪对C_(60)及其硝基衍生物的热稳定性进行了研究，结果表明，环境气氛对C_(60)热稳定性影响很大，C_(60)在空气中423.5℃开始分解，放热峰值温度为668.5℃，在氦气中很稳定，仅表现为升华，C_(60)的晶型对其热稳定性也有一定的影响；合成得到的九种硝基富勒烯衍生物都具有较好的热稳定性，分解峰值温度均高于350℃；产物4的5秒爆发点测试结果为253℃。

In Chapter four, the stability problem of the nonlinear open-loop control system is discussed by the concept of input-output stability. The L〓 stability is defined, the relationship between the L〓 norm of output variable and the input variable is proven firstly, and the sufficient condition for the stability of open-loop system , the H〓 norm of the n-th order frequency response function decreasing by n!

本章给出了非线性控制系统L〓稳定性的定义，首次严格证明了输出变量的L〓范数与输入变量的L〓范数之间的一个重要的关系式，并得到了一个开环系统L〓稳定性的充分条件，即n阶广义频率响应函数的范数〓应按n！

Advantages include thermal stability, non-wetting and elimination of inclusions from shot.· Roll Caster Tips- Ceramic tips offer improved thermal stability, non-wetting, and contain no shot.· Block Caster Tip- Ceramic tips offer improved thermal stability, increased hot strength and do not outgas.· Belt Caster Tips- Ceramic tips offer improved thermal stability, increased hot strength, non-wetting, and do not outgas.

优势包括热稳定性，非焊接和除去钢丸中的杂物·滚动铸造机刀片——陶瓷刀片提供热稳定性，非焊接，不包括钢丸·块铸造机刀片——陶瓷刀片提供热稳定性，增加热强度，不泄露气体·带式铸造机刀片——陶瓷刀片提供热稳定性，增加热强度，非焊接和不泄露气体。

Through the research of direct search method based on 3D FEM, and its application for the tunnel slope stability analysis, the objectives of this work in this paper are as follows:1. The dynamic programming as well as its application for 3D side slope stability analysis is studied. With the introduction of graph theory concept, one kind of glide pattern of 3D slope is constructed, and the critical slip surface with smallest safety factor is searched with the aid of one auxiliary function including safety factor;2. Using the C++ programming language, the 3D slope stability analysis and the direct search procedure is established, and this method is testified applicably by some contrast analysis, also some influence factor in analysis is discussed;3. Integrated with the different actual situation in tunnel slope, considered its excavation, timbering and rain infiltration, its stability influence and rule is researched used this method, also some processing measure is proposed.

本文通过对三维有限元直接搜索法的研究，并将其应用于隧道边坡的稳定性分析中，主要的研究内容有：1、研究了动态规划原理及其在三维边坡稳定性分析中的应用，引入图论概念，构筑出一种边坡三维滑裂面的滑动模式，借助一个包含安全系数的辅助函数并通过动态搜索求得临界滑裂面与最小安全系数；2、采用C++程序设计语言，编制出边坡三维稳定性分析以及直接搜索法的程序，通过一些算例的对比分析，验证本文方法的适用性，并讨论了三维分析中的一些影响因素。3、结合隧道边坡的不同实际情况，考虑施工开挖过程、衬砌结构及降雨渗流等方面的因素，利用本文方法研究对其稳定性的影响和规律，并提出处理措施

Now she was hungry and angry.She began to smoulder.

现在她又饿又气，她开始流露难以抑制的怒火。

You have placed our iniquities before You, Our secret sins in the light of Your presence.

诗90：8 你将我们的罪孽摆在你面前、将我们的隐恶摆在你面光之中。