...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>International Journal of Electrical Power & Energy Systems >Impact of DC bias on differential protection of converter transformers
【24h】

Impact of DC bias on differential protection of converter transformers

机译：直流偏置对换流变压器差动保护的影响

获取原文
获取原文并翻译 | 示例
   

获取外文期刊封面封底 >>

       
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Converter transformers in high-voltage direct current (HVDC) systems are often subjected to DC bias induced by earth return currents (ERCs) from HVDC systems or by geomagnetically induced currents (GICs). DC bias may adversely affect the performance of converter transformers, but its impact on the protection of converter transformers remains uncertain. This paper thoroughly investigates the response of converter transformer differential protection under the effect of DC bias. The network was simulated in PSCAD/EMTDC, and the modeled components included the converter transformers, the current transformers (CTs), and the DC bias signatures. The fault currents generated by the simulator were downloaded into a numerical relay and its operating behavior was observed. The results indicated the pre-existing harmonics, induced by DC bias, do not cause harmonic blocking to incorrectly inhibit the relay for in-zone faults; and any spurious trip, caused by DC bias, can be prevented by appropriate harmonic blocking and the use of a higher slope 2 in the differential current versus bias current characteristic. It was demonstrated the low-frequency characteristic of GIC did not pose any new threats to differential protection. This indicates the low-frequency characteristic of GIC is negligible when investigating the impact of GIC.
机译：高压直流（HVDC）系统中的换流变压器通常会受到来自HVDC系统的接地电流（ERC）或地磁感应电流（GIC）感应的直流偏置。直流偏置可能会对换流变压器的性能产生不利影响，但是其对换流变压器保护的影响仍然不确定。本文深入研究了直流偏置作用下变流器变压器差动保护的响应。该网络在PSCAD / EMTDC中进行了仿真，建模的组件包括换流变压器，电流互感器（CT）和直流偏置信号。由模拟器生成的故障电流被下载到数字继电器中，并观察其运行行为。结果表明，由直流偏置引起的预先存在的谐波不会引起谐波阻塞，从而无法正确抑制继电器在区域内发生故障。直流偏置引起的任何寄生跳闸都可以通过适当的谐波阻断和在差分电流与偏置电流特性中使用较高的斜率2来防止。事实证明，GIC的低频特性并未对差动保护构成任何新的威胁。这表明在调查GIC的影响时，GIC的低频特性可以忽略不计。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号