整流器出口设置平衡电阻桥接地方案的研究
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摘要
超/特高压变电站存在大量整流器独立供电的直流不接地电源系统,这些系统对地无电气联系,不能测量正负极对地电位。文中分析了直流不接地系统在变电站运维检修期间存在的问题,尤其在隔离开关控制回路故障检查期间遇到的难题。提出整流器内部出口配置平衡电阻桥接地,使直流系统对大地建立电气联系的方案。所提方案解决了变电站直流不接地系统不能测量正负极对地电压和检测对地绝缘问题,极大方便了直流系统运维检修工作,同时不影响原直流系统工作特性。建议整流器生产厂家据此改进产品出口电路。
Ungrounded Direct Current( DC) System powered by independent rectifier is extensively used in EHV and UHV power station. These systems have no electrical contact with the earth,so there is no way to measure the voltage of positive and negative pole to ground. This paper analyzes the problems existing in ungrounded DC systems' operation and maintenance work,especially the problems encountered during the fault check work on switches control circuit. A scheme that a balanced resistance bridge is set on rectifier's outlet for setting up electrical connection between the system and earth. This scheme solves the problem that voltage and insulation between ungrounded DC system's positive and negative pole to ground can't be measured,which greatly facilitates the operation and maintenance work of the DC system. Meanwhile,the operating characteristics of the original DC system are not affected. It is recommended that rectifier manufacturers improve the product outlet circuit accordingly.
Ungrounded Direct Current( DC) System powered by independent rectifier is extensively used in EHV and UHV power station. These systems have no electrical contact with the earth,so there is no way to measure the voltage of positive and negative pole to ground. This paper analyzes the problems existing in ungrounded DC systems' operation and maintenance work,especially the problems encountered during the fault check work on switches control circuit. A scheme that a balanced resistance bridge is set on rectifier's outlet for setting up electrical connection between the system and earth. This scheme solves the problem that voltage and insulation between ungrounded DC system's positive and negative pole to ground can't be measured,which greatly facilitates the operation and maintenance work of the DC system. Meanwhile,the operating characteristics of the original DC system are not affected. It is recommended that rectifier manufacturers improve the product outlet circuit accordingly.
引文
[1]程飞.直流系统异常导致的保护误动作分析及防范措施[J].电气应用,2016,35(24):47-51.
[2]王辉,孙梅迪,黄守道,等.高频链矩阵整流器的研究综述[J].电网技术,2017,41(3):969-977.
[3]朱丹,毛亚辉,王琴,等.基于三电平拓扑的充电机控制策略研究[J].电力电子技术,2017,51(2):8-10.
[4]刘涛,李凤旭,杨光,等.直流不接地系统临时接地装置在特高压南阳变电站的应用[J].电气应用,2015,34(1):116-119.
[5]刘涛,裴东良,徐瑞娜,等. 1 000 k V HGIS隔离/接地隔离开关控制触点频繁烧损事故分析及改进[J].华北电力技术,2017(5):60-65.
[2]王辉,孙梅迪,黄守道,等.高频链矩阵整流器的研究综述[J].电网技术,2017,41(3):969-977.
[3]朱丹,毛亚辉,王琴,等.基于三电平拓扑的充电机控制策略研究[J].电力电子技术,2017,51(2):8-10.
[4]刘涛,李凤旭,杨光,等.直流不接地系统临时接地装置在特高压南阳变电站的应用[J].电气应用,2015,34(1):116-119.
[5]刘涛,裴东良,徐瑞娜,等. 1 000 k V HGIS隔离/接地隔离开关控制触点频繁烧损事故分析及改进[J].华北电力技术,2017(5):60-65.