真双极柔性直流电网中性区域金属性接地故障保护策略OA
Protection Strategy for Neutral Area Metal Ground Fault of True Bipolar VSC Based DC Grid
真双极结构的柔性直流电网中性区域发生故障时,故障电流可能很小,传统的差动保护无法识别故障.针对上述问题,首先分析了四端柔性直流电网中性区域故障时的故障特征,介绍了金属回线监视装置和接地电阻阻抗监视装置的工作原理;然后结合极控制保护装置,提出了一种适用于真双极结构的柔性直流电网中性区域的金属性接地故障保护策略,该策略通过调整双极运行状态与系统接地点来增大故障电流,从而使保护动作,隔离故障;最后通过MATLAB搭建四端柔性直流电网模型,验证了该策略对于真双极柔性直流电网中性区域金属性接地故障的有效性.
When the fault occurs in the neutral region of the voltage source converter(VSC)based DC grid with true bipolar structure,the fault current may be very small,and the traditional differential protection cannot identify the fault.For the above problem,it first-ly analyzes the fault characteristics of four-terminal VSC based DC grid neutral zone,and the working principles of the metal loop monitoring device and introduces the grounding resistance and impedance monitoring device.Combined with the pole control protection device,it proposes a protection strategy for the neutral area metal ground fault of the true bipolar VSC based DC grid,by adjusting the bipolar operation status and system ground to increase the fault current,so that it enables the protection to act and isolate the fault.Fi-nally,it establishes a four-terminal VSC based DC grid model through MATLAB,which verifies the effectiveness of this strategy for the neutral area metal ground fault of the true bipolar VSC based DC grid.
李金卜;张荣博;王卫龙;陈思宇;杨杰
国网冀北电力有限公司超高压分公司,北京 102488合肥工业大学电气与自动化工程学院,安徽 合肥 230041国网冀北电力有限公司超高压分公司,北京 102488国网冀北电力有限公司工程管理分公司,北京 100160国网冀北电力有限公司超高压分公司,北京 102488
信息技术与安全科学
柔性直流电网中性区域接地故障金属回线监视接地电阻阻抗监视
VSC based DC gridneutral grounding faultmetal loop monitoring devicegrounding resistance and impedance moni-toring device
《东北电力技术》 2026 (3)
14-19,6
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