基于EEMD-HHT的双馈感应发电机定子匝间短路故障研究

Study on Stator Inter-Turn Short Circuit Fault in Doubly-Fed Induction Generators Based on EEMD-HHT

采用多回路理论构建电路模型,通过MATLAB进行不同故障的仿真,经分析得出定子匝间短路电流的谐波特性以及电压不平衡故障电流的谐波情况,对比可知二者谐波特性相类似,难以通过故障电流区分两种故障。用EEMD-HHT方法分析处理故障电流后,两种故障所得的现象不同,由此很好地区分了这两种故障情况,在定子匝间短路故障的诊断中,排除了电压不平衡故障的干扰,同时该方法还能得出电机故障的发生时刻,可以为定子匝间短路故障检测提供更加可靠的保障。

The multi-loop theory was used to construct the circuit model, different faults were simulated by MATLAB. The harmonic characteristic was got by analyzing the stator inter-turn short circuit current and unbalance voltage fault current, and it was difficult to distinguish between the two faults through current, due to the feature of two faults was similar. After processing the fault current by using EEMD-HHT, two different results were obtained, then two kinds of fault were distinguished easily, the voltage unbalance fault was ruled out on the diagnosis of stator inter-turn short circuit fault, meanwhile, failure time of generator could be got in time. This method provided more reliable guarantee for stator inter-turn short circuit fault detection.