国家电网专业技术人员电力英语水平考试(补全短文)

P1 Functions of power transmission

The function of (power transmission)is to send power from power plants to load center or to exchange power between networks in order to attain the generation-consumption balance or the supply-demand balance between (power networks)、Power transmission is pleted by step-up substations, (step-down substations and connected transmission equipment)、The transmission line mainly consists of the transmission conductors (transmission at high voltage) can reduce the line loss and the voltage drop, ensure the power quality, raise the economy of (power network operation)、The increase of transmission line voltage can not only raise the amount of transmitted power, but also reduce the line loss and line voltage drop, and improve the voltage quality、

功率传输功能

(输电)得功能就是要把电力从发电厂负荷中心或功率交换网络之间为了达到代消费平衡或供求之间得平衡(电网)。电力传输就是通过升压变电站完成,(降压变电站与连接传输设备)。输电线路主要由输电导线(高压输电),可以减少线路损耗与电压降,保证电能质量,提高经济性(电网运行)。输电线路电压得增加不仅可以提高输电线路得传输功率,而且可以降低线路损耗与线路压降,提高电压质量。

A 、step-down substations and connected transmission equipment降压变电站与连接传输设备

B、power network operation 电网运行

C、power transmission 功率传输

D、transmission at high voltage 高压直流输电

E、power networks一。电力网络

P2 A brief introduction on the development of supercritical boilers and their main advantages

In ( some advanced countries )such as U、S、A, Japan and European countries, the supercritical boiler has been developed since the 60s of last century、It has been proved by data and experience, the supercritical unit has (great advantages on economy and environmental protection)、As for its reliability, because the steam-water flow passages in supercritical boiler is same as that in the (subcritical once-through boiler),there isn’t anything special, But as far as hydraulic characteristic, a symbol of reliability, is concerned, in a supercritical boiler, under supercritical condition, medium is of single phase which has a (good homogenization of distribution)、So that the problem caused by uneven distribution of steam phase and water phase can be avoided、It is admitted that, if (whole process management is strengthened), both supercritical and subcritical units can get an excellent reliability index、

超临界锅炉得发展及其主要优点

在(发达国家)如美国,日本与欧洲国家,超临界锅炉已自上世纪60年代以来发达。数据与经验证明,超临界机组具有经济与环境保护得巨大优势。作为其可靠性,因为在超临界锅炉得水蒸汽流通道相同得作为,在得(亚临界直流锅炉),那里就是没什么特别,但至于水力特性,可靠性得象征,有关,在超临界锅炉,超临界条件下,介质就是单相(良好得同质化分布)。从而避免了汽相、水相分布不均造成得问题。这就是承认,如果(全过程管理加强),超临界与亚临界机组可以得到一个极好得可靠性指标。

A、good homogenization of distribution 良好得均匀分布

B、some advanced countries一些发达国家

C、whole process management is strengthened全过程管理加强

D、great advantages on economy and environmental protection具有经济与环境保护得巨大优势

E、subcritical once-through boiler亚临界直流锅炉

P3 Circuit breaker

Circuit breakers are automatically operated high voltage (or high current) switches、Circuit breakers are required (to control electrical power networks)by switching circuits on, by carrying load and by switching circuits off under manual or automatic supervision、Their duty is as follows: In closed position the circuit breaker must be a good conductor for the normal load current、In operating the circuit breaker must be able contacts shall have full insulation level、At operation the circuit breaker must close be able (to switch the current which can be from a few amperes)to many thousands of amperes, and independently of the characteristics from purely inductive to fully capacitive、At closing operation the circuit breaker must close fast and be safe also against full short circuit conditions、They must, therefore, be effective instantaneously when are called upon (to perform any switching operation after long