风电场中性点额定电流与电容电流的配合关系

A Coordination Method for Rated Current of Neutral Point and Grid Capacitance Current in Wind Power Stations

风电场35 k V系统接地变中性点电阻器额定电流通常相对偏低。当集电线路发生经电阻单相接地故障时,集电线路继电保护装置往往难以动作成功。针对该问题,根据电网继电保护运行整定规程,结合电网故障波形,分析了集电线路继电保护装置难以动作成功的原因。在此基础上,提出了中性点电阻器额定电流与电网电容电流的配合关系,并应用于现场,有效提高了风电场集电线路的供电可靠性。

Usually, the rated current of neutral-point grounding resistor in the 35 kV system in wind power stations is relatively low .When a single-phase grounding fault occurs in the power collecting lines , relay protection devices in the power collecting lines are often difficult to operate well .Therefore , possible reasons for this problem is analyzed based on the operation setting regulation of grid relay protection and the fault waveform of the grid .A coordination relationship between the rated current of neutral-point resistor and the grid capacitance current is proposed , which has been applied and effectively improves the power supply reliability of the power collecting lines in 35 kV wind power system .