基于有限元的双馈风力发电机极间导线的故障分析验证

Fault Analysis and Verification of Conductors Between Poles of Doubly-fed Wind Turbines Based on Finite Element

双馈风力发电机转子绕组一般是波形连接的铜排,三相绕组包含三个极间导线,一个中性环。某风电场的一种某型号的双馈风力发电机,发生了多起转子断路故障,经拆解发现,造成发电机转子断路的故障原因为极间导线断裂。本文通过对未断裂的极间导线分析研究,建立极间导线有限元模型,使用有限元软件分析极间导线受力情况,对极间导线断裂做简要分析。通过分析表明,该极间连线的结构设计存在严重的应力集中,最终疲劳断裂。同时,极间导线的固定方式不合理,在振动的影响下,极间连线与转子绕组端部之间的绝缘受损,导致相间短路。

The rotor winding of the doubly-fed wind generator is generally a copper bar connected in a waveform,and the three-phase winding contains three inter-pole wires and a neutral ring.A certain type of doubly-fed wind power generator in a wind farm had several rotor open-circuit failures.After disassembly,it was found that the cause of the generator rotor open-circuit fault was the broken wire between the poles.In this paper,the finite element model of the inter-electrode wire is established by analyzing and researching the unbroken inter-electrode wire.The finite element software is used to analyze the force of the inter-electrode wire,and the break of the inter-electrode wire is briefly analyzed.Analysis shows that the structural design of the interconnection between the poles has serious stress concentration,and finally fatigue fracture.At the same time,the fixing method of the wires between the poles is unreasonable.Under the influence of vibration,the insulation between the wires between the poles and the end of the rotor winding is damaged,resulting in a short circuit between the phases.