文档介绍：火电厂AVC工程设计及应用
【摘要】:A VC是近年来电网自动化建设方面提出的现代电网调度电压质量控制新技术之一。频率和电压是衡量电能质量的两大指标。AGC侧重频率控制,AVC 则侧重于电压控制。AVC的复杂程度远远大于AGC,因为它不但要考虑发电机组的无功控制,还要兼顾电容器、电抗器以及变压器分接头的投切和控制,且约束条件也远多于AGC, 因此AVC系统是一项复杂的系统工程。
给定电压约束条件和自动装置的作用下,发电机的励磁、变电站和用户的无功补偿装置的出力以及变压器的分接头都能按指令自动进行闭环调整,使其注入电网的无功逐渐接近电网要求的最优Q值,从而使全网有接近最优的无功电压潮流,这个过程叫自动电压控制( A u t o m a t i c V o h a g e C o n t r o l , 简称 A V C) , 它是现代电网电压质量控制的一项重要功能。本文从原理、设计、施工调试全过程,着重对方案及工程设计、安装、调试中应注意的问题进行剖析,提出具体方案,最终达到陕西省调的要求,系统的对灞桥热电厂AVC系统建设进行了全面描述和总结。
【关键词】:AVC 基本原理工程设计应用
【Abstract】:AVC is put forward in recent years the development of new technology of modern power grid dispatching of. As everyone knows, the frequency and quality of electric energy quality quantity is measured by two indexes. AGC focuses on frequency control, AVC focus voltage control. plex is far greater than AGC, because it not only consider the generator reactive power control, but also take into account the capacitors, reactor and transformer tap head for the switching and control, and the constraint condition is also far more than AGC, so AVC system is plicated system engineering.
In the automatic device action and a given voltage constraint conditions, the generator excitation, and the user substation reactive pensation device and the output transformer tap can automatically according to instructions for the closed-loop adjustment, make it into the power grid reactive power gradually close to the optimal value of Q and power requirements, so that the work is close to the optimal voltage and reactive power flow, this process is called automatic voltage control ( A u t o m a t I C V o h a g e C o n t r o l, A V C ), it is the modern power grid control is an important function.
【Key words】: Thermal power plant AVC system basic principle and engineering design and Application
一、电压的基本含义:
电压是指电路中两点A、B之间的电位差(简称为电压),其大小等于单位正电荷因受电场力作用从A点移动到B点所作的功。电压在国际单位制中的主单位是伏特(V),简称伏,用符号V表示。
电压质量有两个指标,一个为频率,另外一个很重要的参数就是电压偏差。
根据国标12325-2003《电能质量供电电压允许偏差》规定,电压偏差允许值如下:
1)35kV及以上供电