问题 问答题 简答题

简述微机保护的基本构成和主要部分的功能?

答案

参考答案:

微机保护是由一台计算机和相应的软件(程序)来实现各种复杂功能的继电保护装置。微机保护的特性主要是由软件决定的,具有较大的灵活性,不同原理的保护可以采用通用的硬件。

微机保护包括硬件和软件两大部分。硬件一般包括以下三大部分。

(1)模拟量输入系统(或称数据采集系统)

包括电压形成、模拟滤波、采样保持、多路转换以及模数转换等功能,完成将模拟输入量准确地转换为所需的数字量。

(2)CPU主系统

包括微处理器(MPU)、只读存储器(EPROM)、随机存取存储器(RAM)以及定时器等。MPU执行存放在EPROM中的程序,对由数据采集系统输入至RAM区的原始数据进行分析处理,以完成各种继电保护的功能。

(3)开关量(或数字量)输入/输出系统

由若干并行接口适配器、光电隔离器件及有接点的中间继电器等组成,以完成各种保护的出口跳闸、信号警报、外部接点输入及人机对话等功能。

微机保护软件是根据继电保护的需要而编制的计算机程序。

阅读理解

第二部分阅读理解(共20小题;每小题2分,满分40分)

“How can I learn English well?” This is a question many students ask. In my opinion, the most effective way is to learn lessons by heart. If you can recite the text and write it out, you’ve learned it fairly well. And if you can tell, in your own words, what the lesson says you’re a very successful learner indeed. Your English will be quite perfect.

This is a difficult task. However, if you try to learn by heart only part of each lesson, you’ll find it not half so hard as you might have thought.

Learning this way, you will make rapid progress. Of course, writing is also necessary. It helps you a lot on our way to success in English.

Equally important is to feel the language. You should be able to laugh at jokes and be shocked at bad news. When using English, try to forget your mother tongue. Instead of helping you, your own language gets in your way. So, never try to see English through translation.

1.In the writer’s opinion, the most effective way in learning English is ____.

A. to practise speaking, writing and feeling it

B. to forget your own native language

C. to translate everything into his own language

D. to memorize the English words and grammatical rules

2. “Instead of helping you, your own language gets in your way.”This sentence means that memorizing your own language can ________.

A. help you to study English well        B. stop you mastering English

C. make English easy to learn                     D. help you notice mistakes

3.Equally important is to feel the language. “to feel the language” here means_____.

A. to get a knowledge of English by touching

B. to be able to read and write English

C. to translate English into your own by imagining

D. to be able to experience the rich sensation of the language

B    

判断题