电网

Respectively big middle of the whole nation city urban area electrified wire netting plain conductor reforming , prospect.

市场前景：目前电力部对全国各大中城市城区电网裸线的改造，前景十分看好。

Marketplace prospect: The electric power headquarter looks to further increase at present very to respectively big middle of the whole nation city urban area electrified wire netting plain conductor reforming , prospect.

市场前景：目前电力部对全国各大中城市城区电网裸线的改造，前景十分看好。

With regard to the software design, we realized the software filter for anti-intermixing; and we use the Fast Fourier Transform Algorithm to analyze the harmonic of the voltage and current; also we analyze the method of calculating all the parameters of the power system, fault component and positive, negative, zero sequence.

软件算法方面，系统对信号采用了抗混叠软件滤波，并采用传统的快速傅立叶变换，对采样的电压和电流信号进行频谱分析。论文中还详细分析了电网各参数，故障分量以及正、负、零序分量的计算。

Distribution automation is to monitor, control and protect the power equipment in the distribution network.

配电自动化，就是对配电网中的电力设备实现监测、控制和保护的系统。

The research and development of Electricity Management System in Power Distribution Network based on GIS is presented in this paper.

本文研究开发了基于GIS平台的配电网用电管理系统。

With the rapid development of modern electric power industry and the expansion ofthe power grid in China power system dynamics become more and more complex.

随着我国电力工业的快速发展，电网规模的逐步扩大，电力系统动态特性也变得越来越复杂。

That power grid failure left 50 million people in the dark and cost the nation more than 6 billion.

那次电网故障让 5 千万人处于黑暗之中，并在全国造成超过 60 亿美元的损失。

Apparently, their security is directly related to the reliability of the operation of national power grids. Whereas wind loading is one of the key factors which impact the reliability.

显然，它们的安全性直接关系到国家电网运行的可靠性，而风荷载是影响它们安全性的主要因素之一。

In the design of the power supply, the main circuit topology frame uses half-bridge series resonant switching and parallel load connection, in which, an IGBT is adopted as the power switches, and features high operation frequency, high output power and fast response. In addition, the IGBT in the switch mode power supply has no hard turn-on or turn –off situation in transition, thus the disturbance to the power system is avoided.

相应的激光电源采用半桥软开关技术，串联谐振并联输出，IGBT 为主控制元件，实现了高频工作、高功率多路输出，响应快速；脉冲模式工作时避免了开关管的硬开关，减小了高次谐波对电网的干扰；无需镇流电阻也可实现气体稳定放电等特性。

In the design of the power supply, the main circuit topology frame uses full-bridge series resonant switching and parallel load connection, in which, four MOSFETs are adopted as the power switches, and by four pulses which UC3879 produces, high frequency operation and fast response are realized. In addition, the MOSFET in the switching power supply has no hard turn-on or turn-off situation in transition, thus the disturbance to the power system is avoided. Especially,by the use of high frequency transformer, PQ50/50, the switching power system can provide the steady discharge current without any amperite.

此开关电源采用全桥软开关技术、串联谐振并联输出，四个MOSFET管为主控制开关元件，通过脉冲产生电路UC3879产生的四路相关脉冲实现了高频交替开关，同时能快速响应输出的各种变化；避免了开关管的硬开关，提高了转换效率，另外通过采用高频变压器PQ50/50隔离了原副边，减小了高次谐波对电网干扰；无需镇流电阻也可实现气体稳定放电。

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。