电气工程及其自动化专业英语 华臻专业英语.11

Specialized English for Electrical Engineering and Automation,Chapter 11 Protections in Electric Power Systems,11.1 Fundamental Principles of Protection 11.2 Overcurrent Protection 11.3 Distance Protections Microprocessor-based Relays,Content,Words and Expressions 1,relay 继电器 A relay is an electrically operated switch. auxiliary relay 中间继电器 intermediate relay 中间继电器 directional overcurrent relay 定向过流继电器 overvoltage relay 过电压继电器 under voltage relay 欠电压继电器 ratio differential relay 比率差动继电器 Phase failure relay 缺相继电器,Words and Expressions 2,short circuits 短路 circuit breaker 断路开关，断路器 voltage transformer 电压互感器 current transformer 电流互感器 line-to-neutral voltage 线与中性点电压 line-to-line voltage 线电压 line-to-ground voltage 对地电压,Words and Expressions 3,secondary side （变压器）的二次侧，副边 embody in 使体现，使具体化 reliability 可靠性 transmission 输电 distribution 配电 tripping 跳闸 trigger 触发,Words and Expressions 4,primary protection 主保护 backup protection 后备保护 overcurrent protection 过电流保护 distance protection 远距离保护 step-distance protection 分段式距离保护 loss-of-field protection 失磁保护 out-of-step protection 失步保护 pilot protection 纵联保护,Sentences 1,1. The protection systems not only protect the faulty equipment from more serious damage, they also protect the power system from the consequences of having faults remain on the system for too long.,保护系统不仅保护故障设备免受更严重的破坏,也使电力系统避免了长时间产生故障造成的影响。,Sentences 2,2 The power handling capability of the transducers is expressed in terms of the volt-ampere burden, which they can supply without significant waveform distortion. In general, the transient response of the transducers is much more critical in relaying applications.,伏安负荷决定了互感器的功率处理能力，只要互感器的伏安负荷（曲线）无明显的波形畸变（都可运行）。一般来说，互感器的瞬态响应（性能）在继电保护应用中（要求）更严格。,Sentences 3,3 This is the device that, using the current, voltage, and other inputs, can determine if a fault exists on the system, for which action on the part of the relay is needed.,继电器以电流、电压或其他输入信号确定应执行哪一个动作，来确定系统是否存在故障。,Sentences 4,4 A fault in that zone must be isolated by tripping circuit breakers X and Y. While the breaker X is near the transformer and can be tripped locally, Y is remote from the station, and some form of communication channel must be used to transfer the trip command to Y.,区域A的故障必须由跳闸断路器X和Y切除，断路器X靠近变压器，可就近跳闸。Y远离变电站，必须采用某种通信通道将跳闸指令传送给Y。,5. When a protection system is intended as a backup system for some other protection, it is necessary to deliberately slow it down so that the primary protection may operate in its own time before the backup system will operate.,当一个保护系统作为其他保护的后备系统时，有必要使其后备保护动作减慢，使主保护在后备系统动作以前，可以在规定时间内切除故障。,Sentences 5,Sentences 6,6 A secure relay is one that will not operate for conditions for which it is not intended to operate.,可靠的继电器在不预动作的情况下不会产生动作。,Sentences 7,7. Dependability means that the protection should react and do its action when a fault occurs for which it is designed to react for.,可靠性是指针对某种故障设计的保护，在此故障发生时能作出反应并采取保护行为。,Sentences 8,8. These protections measure the difference between two currents, which in normal operation should be equal, and the protection is activated if this deviation exceeds a predetermined value. Both differences in amplitude and phase can trigger the relay.,这些保护测量的是两个电流的差值，正常运行下这两个电流是相等的。如果电流差超过一个预定值，就会启动保护。电流在幅值和相位上的差值都可以触发保护。,