特高压

Considering the factors such as randomness of natural lightning locus and the coexistence of primary and secondary leaders, it is necessary to lead in the concept of dynamic lightning protection shielding angle. It is suggested that the angular bisector of practical protective angle formed by ground wire or earth pin in UHVAC transmission line and conductor should be aligned with the direction of lightning leader as well as the ratio of vertical span to horizontal span and the impact of wind speed should be considered.

考虑自然闪电轨迹的随机性和雷电主先导与次先导并存现象等因素，有必要引入动态防雷保护角概念，建议特高压交流线路中地线对导线的实际保护角形成的角平分线应与雷电先导的来向一致，并应计及垂直档距和水平档距的比值和风速的影响。

Commutation failure is one of the most common failures for the high voltage direct current transmission system .

在特高压直流输电中换相失败也是主要的故障。

The proposed magnetic circuit decomposition approach is clear in principle, easy in modeling, precise in simulation result, applicable in engineering, suitable for power system electromagnetic transient calculation, and provides necessary simulation means for UHV and EHV MCSR analysis.

文中提出的磁路分解仿真建模法具有原理清晰、建模简便、模型精确、工程适用的特点，适用于电力系统电磁暂态计算，为超/特高压MCSR的分析提供了必要的仿真手段。

The finite element method is applied to calculate electric field intensity of ultrahigh voltage compact transmission lines.

将有限元方法应用于特高压紧凑型输电线路电场强度的计算。

It's hopeful that the research is useful to the security and economy of the coming looped electromagnetically coupled power networks of 750 kV and EHV power grid in China.

该研究有望对我国750 kV和特高压电网发展过程中形成的电磁环网的安全、经济运行起到一定的指导作用。

Power system ; ultral high voltage power grid ; short circuit current ; limiting measure

电力系统；特高压电网；短路电流；限流措施

The Influences of EHV grid on the short circuit current and reactive compensation in Fujian power grid and the opening of electromagenetically coupled power loop of 1 000 kV and 500 kV are discussed.

分析了特高压电网对福建电网短路电流和无功补偿的影响以及1 000 kV/500 kV电磁环网的解环等问题。

The 1 000 kV transformer is one of the most important equipments for 1 000 kV AC power transmission project.

000 kV变压器是特高压交流输电工程最关键的设备之一。

Discussion on the establishment of bidding document of hydraulic engineering;2. According to the requirements for porcelain-clad metal oxide lightning arresterin bidding document and technical agreement of 1000 kV UHVAC demonstration project issued by SGCC,and to refer to relevant national and international standard and document information,Langfang EPRI Toshiba Lightning Arrester Co.

根据国家电网公司1000 kV特高压交流试验示范工程招标文件及技术协议中对瓷外套金属氧化物避雷器的要求，参照有关国家标准、国际标准及文献资料，廊坊电科院东芝避雷器有限公司应用两项株式会社东芝已有运行实绩的关键技术：减震技术及高强度瓷套设计技术进行了1000 kV瓷外套MOA的抗地震设计。

Through high-performance oil-pipe, in the proposed system the vacuum oil filter, pressuring oil filter, oil tank are combined with transformer or reactor; by means of switching over of oil circuit different oil-filtering functions can be implemented, thus the difficult problems such as the request for high quality of insulating-oil by large-scale oil immersed equipments of UHV substations and the difficulty to disposal large amount of insulating-oil are solved.

该系统把真空滤油机、压力式滤油机、油罐和变压器或高抗等通过高性能油管组合在一起，通过油路的切换实现各种滤油功能，解决了特高压变电站大型油浸设备对绝缘油品质要求高、油量大不易处理的问题。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。