海上风机一体化电磁暂态模型与雷电暂态过电压研究

Electromagnetic transient integration model and transient overvoltage study of offshore wind turbine

为了减小雷击海上风机引发暂态过电压的故障率,需要准确地分析海上风机暂态过电压的影响因素及响应规律。结合海洋接地环境及风机桨叶转动特性,利用电磁场数值计算的方法,建立了一种新型的海上风机一体化电磁暂态模型;利用ATP-EMTP对海上风机进行仿真分析,研究了海水深度、桨叶长度和塔筒高度、雷电流参数、雷击点和桨叶位置对机舱处雷电暂态过电压的影响,并利用波过程理论分析其原因。仿真结果表明,由于雷电流在风机上存在折反射现象,使得机舱处暂态电压存在明显振荡特性;所提影响因素会对暂态电压的峰值和振荡频率产生不同程度的影响。

In order to reduce the failure rate of offshore wind turbine transient overvoltage caused by lightning stroke,it is necessary to analyze the influence factors and response rules of offshore wind turbine transient overvoltage accurately.A novel electromagnetic transient integration model of offshore wind turbine is established by numerical calculation methods for electromagnetic fields,considering the marine grounding environment and rotating characteristics of blades.The offshore wind turbine is simulated in the ATP-EMTP software to analyze the effects of ocean depth,blade length,tower height,lightning current parameters,lightning strike points and blade positions on transient voltage,whose reasons are studied by the wave process theory.Simulative results show that the transient voltage has obvious oscillation characteristics due to the reflection and refraction of lightning current in the wind turbine,in addition,the proposed influence factors have different effects on the transient voltage peak value and oscillation frequency.