摘要
发电厂二次系统是发电厂安全生产、运行维护的重要组成部分，对电力系统安全、可靠运行有着极其重要的作用。实践证明，技术先进的电气二次系统能对电气一次系统进行监测、报警、控制、保护，并能快速、准确、可靠地预报和切除故障，是一次系统安全、可靠、经济运行的重要保证。
二次系统分为继电保护、发电机励磁系统、直流系统及调速系统几部分。其中继电保护分为发电机保护，主变压器保护，线路保护和厂用电保护，通过对短路电流的计算确定保护类型和保护用设备的参数。
发电机励磁调节系统设计成由两套数字式调节器构成，两台互为备用，故障时自动切换；直流系统包括直流电源系统和蓄电池组；调速器系统中调速器应具备PID调节规律。
关键词：二次系统，继电保护，整定计算
ABSTRACT
Power secondary system is an important component of the power plant safety in production, operation maintenance, the power system safe and reliable operation has a very important role. Practice proves that the advanced technology of electrical secondary system to electric a system for monitoring, control, alarm, protection, and can quickly, accurately and reliably forecast and removal of fault, is a system the important guarantee of safe, reliable and economic operation.
Secondary system was divided into relay protection, generator excitation system, dc system and governing system parts. The relay protection can be divided into generator protection，main transformer protection, line protection and protection, auxiliary power to determine the calculation of short-circuit current protection type and protection with the parameters of the equipment.
Generator excitation control system designed to be composed of two sets of digital regulator, two mutually standby, fault automatic switch; Dc system consists of dc power supply system and battery; The speed governor system of speed governor should have PID control law.
Keywords: secondary system，relay protection，setting calculation
目录
1 绪论 ..................................................................................................................................................... 1
1.1 引言 .......................................................................................................................................... 1 1.2 崖羊山水电站简介 ................................................................................................................... 1 2 发电机继电保护系统 .......................................................................................................................... 2
2.1 故障类型及不正常运行状态 ................................................................................................... 2
2.1.1 故障类型 ........................................................................................................................ 2 2.1.2 不正常运行状态 ............................................................................................................ 2 2.2 发电机继电保护类型 ............................................................................................................... 2
2.2.1 主保护 ............................................................................................................................ 2 2.2.2 后备保护 ........................................................................................................................ 2 2.3 发电机纵联差动保护 ............................................................................................................... 2
2.3.1 发电机纵联差动保护原理及接线 ................................................................................ 3 2.3.2 发电机纵联差动保护整定原则 .................................................................................... 3 2.4 发电机定子绕组单相接地保护 ............................................................................................... 4
2.4.1 利用零序电流构成的定子接地保护 ............................................................................ 4 2.4.2 利用零序电压构成的定子接地保护 ............................................................................ 5 2.4.3 100%定子接地保护 ....................................................................................................... 5 2.5 横差动保护............................................................................................................................... 5 3 主变压器继电保护系统 ...................................................................................................................... 7
3.1 故障类型及不正常运行状态 ................................................................................................... 7
3.1.1 故障类型 ........................................................................................................................ 7 3.1.2 不正常运行状态 ............................................................................................................ 7 3.2 变压器的继电保护类型 ........................................................................................................... 7 3.3 变压器的纵联差动保护 ........................................................................................................... 8
3.3.1 变压器纵联差动保护的原理和接线 ............................................................................ 8 3.3.2 变压器纵联差动保护在稳态情况下的不平衡电流及减小不平衡电流的措施 ........ 9 3.4 变压器纵联差动保护整定计算 ............................................................................................. 10
3.4.1 变压器参数 .................................................................................................................. 10 3.4.2 基本侧的确定 .............................................................................................................. 10 3.4.3 计算差动保护装置基本侧的动作电流 ...................................................................... 10 3.4.4 确定BCH-2型差动继电器各线圈的匝数 ................................................................ 11
3.4.5灵敏度校验 .................................................................................................................. 12 3.5 变压器相间短路的后备保护 ................................................................................................ 12
3.5.1 变压器相间短路的过电流保护 .................................................................................. 13 3.5.2 低电压启动的过电流保护.......................................................................................... 13 3.5.3 复合电压启动的过电流保护...................................................................................... 13 3.5.4 负序过电流保护 ......................................................................................................... 14 3.6 变压器的瓦斯保护 ................................................................................................................ 14
3.6.1 变压器瓦斯保护的范围 ............................................................................................. 14 3.6.2 瓦斯继电器的动作原理 ............................................................................................. 15 3.6.3 瓦斯继电器收集气体判别故障 .................................................................................. 15 3.6.4 轻、重瓦斯保护动作的原因...................................................................................... 15
4 母线保护及断路器失灵保护简介 ................................................................................................... 17
4.1 母线保护简介 ........................................................................................................................ 17 4.2 母线差动保护的工作原理、保护范围................................................................................. 17
4.2.1 固定连接的母线差动保护.......................................................................................... 17 4.2.2 母联电流相位比较原理的母线差动保护 .................................................................. 18 4.2.3 比相式母线差动保护 ................................................................................................. 18 4.3 断路器失灵保护简介 ............................................................................................................ 18
4.3.1 失灵保护的原理及框图 ............................................................................................. 18 4.3.2 失灵保护跳闸的可能原因.......................................................................................... 19 4.3.3 失灵保护动作跳闸的处理.......................................................................................... 19
5 厂用电的继电保护 ........................................................................................................................... 20
5.1 厂用电抗器保护 .................................................................................................................... 20
5.1.1 工作电抗器差动保护 ................................................................................................. 20 5.1.2 工作电抗器过电流保护 ............................................................................................. 20 5.1.3 工作电抗器单相接地保护.......................................................................................... 20 5.1.4 备用电抗器过电流保护 ............................................................................................. 20 5.1.5 备用分支过电流保护 ................................................................................................. 20 5.1.6 单相接地保护 ............................................................................................................. 20 5.2 低压厂变及备变保护 ............................................................................................................ 20
5.2.1 厂用变压器的故障 ..................................................................................................... 21 5.2.2 差动保护 ..................................................................................................................... 21 5.2.3 瓦斯保护 ..................................................................................................................... 21 5.2.4 过电流保护 ................................................................................................................. 21 5.2.5 零序过电流保护 ......................................................................................................... 21 5.3 电容器的保护 ........................................................................................................................ 22
5.3.1 电容器组常见的故障和异常运行情况 ...................................................................... 22 5.3.2 电容器组应配置的如下的保护装置 .......................................................................... 22 5.3.3 电容器组的电压保护 .................................................................................................. 22
6 发电机励磁系统概述 ........................................................................................................................ 24
6.1 配置简介................................................................................................................................. 24 6.2 同步发电机励磁系统的构成及要求 ..................................................................................... 24
6.2.1 构成.............................................................................................................................. 24 6.2.2 对同步发电机励磁系统的要求 .................................................................................. 25 6.3 同步发电机励磁系统的分类及其性能特点 ......................................................................... 25
6.3.1 直流励磁机励磁系统 .................................................................................................. 25 6.3.2 交流励磁机励磁系统 .................................................................................................. 25 6.3.3 发电机自并励系统（没有励磁机） .......................................................................... 26
7 水电厂直流系统概述 ........................................................................................................................ 27
7.1 配置简介................................................................................................................................. 27 7.2 直流系统简介 ......................................................................................................................... 27
7.2.1 直流系统的作用及重要性 .......................................................................................... 27 7.2.2 基本概念 ...................................................................................................................... 27 7.3 直流系统的组成及各部件的作用 ......................................................................................... 27
7.3.1 直流系统组成 .............................................................................................................. 27 7.3.2 各组成部件的作用 ...................................................................................................... 27 7.3.3 高频电源开关的特点 .................................................................................................. 28 7.4 直流系统接线方式 ................................................................................................................. 28 8 调速器系统 ....................................................................................................................................... 29
8.1 配置简介................................................................................................................................. 29 8.2 水轮机调速器的任务 ............................................................................................................. 29 8.3 调速器维持发电机组输入和输出能量平衡途径 ................................................................. 29 8.4 水轮机调节系统的组成 ......................................................................................................... 29 8.5 水轮机调节系统的特点 ......................................................................................................... 30 8.6 水轮机调速器的工作原理及系统结构 ................................................................................. 30 9 结论 ................................................................................................................................................... 32 参考文献 ............................................................................................................................................... 33 致谢 ....................................................................................................................... 错误！未定义书签。