基于定时限保护整定计算的实用断点计算方法

结合电力系统定时限保护整定计算的特点,提出了一种新的实用断点计算方法.定义了配合环网和死锁环网的概念,并通过预整定形成死锁环网;在所得死锁环网基础上,将依赖函数扩充分为主依赖函数和后备依赖函数,根据主/后备依赖函数中元素的特点判断死锁环网中是否存在特殊网络结构并进行相应的处理,同时动态地将主依赖函数或后备依赖函数为空的保护从待选断点保护中删除,以保证每一步的断点计算都是针对环网进行.算例表明:本方法能较好地满足国内电力系统定时限保护逐级配合整定计算的要求.

Practical method to determine the breakpoints using definite-time relay coordination

With the increasing complexity in power network configuration, the problem of breakpoints in relay coordination is becoming more and more serious. A new practical method to determine the breakpoints is proposed after the property of relay coordination of definite-time relays in power systems was considered. The concepts of physical loop and deadlock loop were defined separately and the deadlock loop was obtained through pre-coordination. Then, based on the deadlock loop, the dependency function was expanded to two functions including main dependency function and backup dependency function. The special network configurations in deadlock loop were determined and dealt with based on the characteristics of elements in main and backup dependency functions. At the same time, the relay whose main dependency function or backup dependency function was null was deleted from the candidate breakpoints dynamically to ensure that all the steps to determine the breakpoints are used only for deadlock loop. The case studies show that the method presented is more suitable for the relay coordination of definite time relays in power systems in China and is very useful.