摘要
接地变最大的功能就是创造了一个中性点用来连接接地电阻,使不接地系统能够将中性点集聚的多余电荷快速地释放掉,从而限制了内部过电压倍数。系统经接地变接地后,装设的接地保护对零序电流具有足够的灵敏度,为快速切除接地故障提供了可能性。从Z型变结构特点入手,讨论了中性点不接地系统经Z型变及小电阻接地后限制间歇性弧光过电压的原理,Z型变主要安装形式,Z型变及接地电阻选型。并讨论了经Z型变接地后,反映系统单相接地的保护配置,以及对主变压器差动保护的影响及对策。
This paper introduces the characteristic of configuration of zigzag grounding transformers. Based on that, the mode of zigzag grounding transformers the in distribution network with low resistance via neutral grounding is presented. It analyzes the principle of the mode limiting overvoltage due to intermissive arc grounding, the mounting position of zigzag transformers and arrangement principle of earth protection in the distribution network. Moreover, the influence to tansformer differential protection in this mode is discussed and some countermeasures are proposed.
出处
《继电器》
CSCD
北大核心
2006年第14期15-19,共5页
Relay
关键词
Z型变
小电阻
接地
接地保护
电力系统
zigzag transformer
low resistance
grounding
earth protection
power system
