大中型水轮发电机中性点配电变压器电阻接地方式设计选型  

Design and Selection of Resistance Grounding Mode for Neutral Distribution Transformer of Large and Medium-sized Hydroelectric Generators

作　　者：任良均 REN Liangjun(Aba Hydropower Development Co.,Ltd.,Aba Prefecture Sichuan 623500)

机构地区：[1]阿坝水电开发有限公司,四川阿坝州623500

出　　处：《四川水力发电》2025年第2期10-13,共4页Sichuan Hydropower

摘　　要：分析了大中型水轮发电机定子绕组单相接地故障电流和故障暂态过电压特征,介绍了发电机中性点经配电变压器接地方式对故障暂态过电压抑制的工作原理,以巴拉水电站发电机中性点接地方式为例,分析计算发电机中性点采用配电变压器电阻接地方式下接地低电阻、配电变压器容量等参数,对接地电阻和配电变压器进行设计选型,并验算发电机中性点经配电变压器电阻接地后的定子单相接地故障电流和暂态过电压是否满足规范要求,以保障发电机安全稳定运行。This paper analyzes the characteristics of single-phase grounding fault current and fault transient overvoltage of stator winding of large and medium-sized hydroelectric generators,and introduces the working principle of generator neutral grounding through distribution transformer to suppress fault transient overvoltage.Taking the generator neutral grounding mode of Bala Hydropower Project as an example,it analyzes and calculates the parameters such as grounding resistor resistance values and distribution transformer capacities under the distribution transformer based resistance grounding scheme,designs and selects the grounding resistance and distribution transformer,and verifies that the stator single-phase grounding fault currents and transient overvoltage after the generator neutral is grounded through distribution transformer resistance meet the specification requirements,so as to ensure the safe and stable operation of the generator.

关 键 词：发电机中性点 配电变压器 接地方式 暂态过电压 

分 类 号：TM54[电气工程—电器]