阻尼振荡

If the roots are complex, the motion will be either a damped or undamped sinusoidal oscillation.

若根是共轭复数动态反应则是有阻尼或无阻尼的正弦振荡

The transient term is an oscillation of damped natural frequency , of which the amplitude decays according to .

瞬态项以阻尼自然振荡频率振荡，其幅值以衰减。

Parameters of the controller are tuned according to the damping ratios of the weakly damped inter-area oscillation modes estimated on line by an improved Prony algorithm.

该控制器使用改进的Prony算法，在线分析得到系统弱阻尼区间振荡模式的阻尼比，并据此通过自寻优的方法调整控制器的参数。

At first, based on the results of the field tests and studies, this paper indicates that there are two kinds of low frequency power oscillations on the weak tie line: one is caused by negative damping, and belongs to the free oscillation; the other is caused by periodic load disturbances and periodic adjustments, and belongs to the forced oscillation.

首先，本文根据现场试验和研究结果指出，互联系统的弱联络线上存在两类性质不同的低频功率振荡：一类是由负阻尼引起的，属于自由振荡；另一类是由于系统周期性负荷扰动或振荡调节等引起的，属于强迫振荡。

Secondly, oscillation energy function of inter-area mode oscillation is defined which can be regarded as a measure of the deflection away from the steady state position during dynamic oscillation period.

分析了功率振荡过程中能量函数的变化，提出了衰减振荡能量的阻尼控制策略，目的是使系统暂态能量以最快的速度归零，即回到故障后的稳定平衡点。

The NEF method is potential in developing new efficient tools for on-line security analysis and control. In study of the method of damping system low-frequency oscillations, this project has proposed the control strategy of oscillation energy function descent.

项目研究中还应用归一化暂态能量函数对电力系统振荡机理进行分析，设计了增加阻尼平抑电力系统振荡的方法，提出了振荡能量函数的概念，得出"振荡能量函数下降法"的控制策略。

Based on the extended Phillips-Heffron model for the multi-machine power system and model control theory, a new model control analysis method of free eigensolution is proposed to select the rational position to configurate power system stabilizer in multi-machine power system.

引言 电力系统中的低频振荡是由于缺乏机械模式阻尼而引起的，为了抑制这种振荡，提高电力系统的阻尼及其稳定性，在电力系统中设置电力系统稳定器(Power system Stabi一izer，Pss)是一种经济而有效的方法〔'，2。

The specific contents are as follows:Firstly, the causes of energy balance method result has some errors is analyzed. Then energy balance method is improved from the following aspects: the wind power input, the conductor self-damping, the damper dissipated power and vibration solution of Stockbridge dampers-conductor coupling system. So that improved energy balance method can consider more influential factors to enhance accuracy.

本文对输电线的微风振动控制和次档距振荡进行了多方面的研究，主要包括能量平衡法的改进、防振锤-输电线耦合系统的振动求解、阻尼线的耗能计算理论、微风振动的室内模拟试验、分裂导线微风振动的精细计算理论、多分裂导线的最大次档距和阻尼间隔棒优化布置等几部分，具体如下：首先分析了微风振动传统计算方法能量平衡法计算误差较大的原因，分别从风能输入功率、输电线自阻尼功率、防振锤消耗功率、输电线-防振锤耦合体系的振动求解等方面，对能量平衡法进行了改进，使能量平衡法可以考虑更多的影响因素以提高求解精度。

This method uses the value of TEF as the assessment of system transient stability and subsequent power oscillation, and pulls the system back to its steady state most rapidly. New control strategy combines transient stability control and damping.

该方法以暂态能量值作为系统经受大扰动后暂稳控制和阻尼后续振荡的指标，使其尽快归零，能同时实现TCSC的暂态稳定控制和对后续功率振荡的阻尼。

Derived the partition law of damping of electromechanical mode, the relation between the real part of electromechanical mode and generators damping is showed in the analytical form.

论文主要内容如下：推导出了多机系统机电振荡模式阻尼分配规律，以解析的形式表示出了振荡模式实部与各台机阻尼的函数关系。

I am accused of being overreligious," she said in her quiet, frank manner,"but that does not prevent me thinking the children very cruel who obstinately commit such suicide.""

客人们在卡罗利娜·埃凯家里，举止就文雅一些，因为卡罗利娜的母亲治家很严厉。

Designed by French fashion house Herm è s, this elegant uniform was manufactured in our home, Hong Kong, and was the first without a hat.

由著名品牌 Herm è s 设计，这件高贵的制服是香港本土制造，是我们第一套不配帽子的制服。