电网

With the development of the electric power industry, the capacitance of a turbo-generator has increasingly become larger, which risk the torsional oscillation in the flexible shaft system of large turbine-generators. The problem of shaft torsional oscillation has become the key technology need to be solved urgently in the development of large power system and unit.

随着电力工业的发展，汽轮发电机组的单机容量正日益大型化，导致机组轴系扭转振动的危害性日益突出，轴系扭振问题已成为发展大电网和大机组所急需解决的关键技术问题。

Then we use IEEE First Benchmark system model and the 500kV system which contain 500MW and 600MW turbo-machines, as typical examples, the shaft systems without exciter in these examples are also analyzed on its impact on torsional oscillation.

首先对采用静止励磁方式的汽轮发电机轴系建模进行了说明；然后以IEEE次同步谐振标准模型和东北电网中伊敏电厂计划安装的500MW和600MW汽轮发电机组为典型算例，研究了改用静止励磁方式对轴系扭振的影响。

The phase space reconstruction theory of chaotic dynamic system, in combination of the non-linear reflecting and pan-capacity of neural network, can be used to establish the prediction model; and a kind of new prediction method is suggested to realize the complete tracing of phase point evolution process and to predict "the price nails", whereby improving the prediction accurateness and effectively solving the problem of negative prediction, with the satisfactory results obtained.

采用混沌理论预测系统边际电价针对我国电力市场电价变化特点，利用电价和负荷时间序列的混沌特性，重构准确的电价序列相空间，通过跟踪相空间相邻相点的演化趋势，建立基于快速BP网络的电价预测模型，对我国川渝电网电价进行预测，取得良好效果利用混沌动力系统的相空间重构理论，结合神经网络的非线性映射和泛化能力建立预测模型，提出一种新的预测方法实现了相点演化过程的全局跟踪，对"价格钉"进行预测，提高了预测精度，有效解决了负预测问题，得到满意的结果。

The photovoltaic steel-making concept is introduced with characteristics of photovohaic effect transformation and off-network by the group.

基于对传统钢铁生产节能减排的思考，探讨了使用清洁能源炼钢的问题，提出了太阳能光伏炼钢概念在技术层面上的特点：一是光电转化，转换过程直接迅速，且不会伴随任何物质转变和化学变化；二是"脱网"，即不与常规的输供电电网相搭接，以保证系统在能量方面的独立性。

While fault occurs, there is a transient or steady -state response to the power network.

出现故障时，对电网有一个暂态或稳态的快速响应。

Influence of DC system control strategy on the transient stability of South China power grid.

直流系统的控制策略对南方电网暂态稳定性的影响。

Monitoring of transient voltage fluctuation is a problem concerned in power quality improving.

电网暂态电压扰动信号的监测是关系到电能质量改善的首要问题。

This paper analyses the wave trapper presents test methods according to the condition of actual work.

高频通道作为高频保护信号的传输通道，它能否正常的工作对于电网的安全可靠运行起着非常重要的作用。

The background of protective relaying based on travelling wave for transmission lines is introduced and its development at home and aboard is reviewed.

0引言全国高压、超高压输电线路的不断扩建及特高压线路的试建，大容量机组的陆续投运，全国电网的互联对电力系统继电保护的动作速度、可靠性、灵敏度等指标提出了更高的要求。

Based on the conversion of trigonometric function ,a novel real-time algorithm of reactive power similar to that of active power is presented,which reactive power is speed-ily and accurately measured by the voltage,current and frequency.

运用三角函数变换的方法，提出了一种新颖的与计算有功功率相似的电网无功功率的离散化实时算法。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。