CAJ | 학술논문

当双馈风力収电机定子绕组収生轻微匝间短路时,故障引起的信号变化十分微弱,三相定子电流的时域波形变化微小,而根据希尔伯特-黄变换(HHT)分析获取信号的时频表示,在故障时刻的突变很明显,从而提取故障特征.在动模实验室进行实验,获取定子在匝间短路瞬变过程的电流信号,对其进行经验模态分解(EMD),提取6层模态分量(IMF)进行Hilbert变换.实验结果显示,不论风机在空载、半载以及额定负载下,在匝间短路开始时,根据第4或者第5层IMF分量的瞬时幅值可以确定出匝间短路的収生,从而可以进行及时的维修,具有一定的工程应用价值.
당쌍궤풍력수전궤정자요조수생경미잡간단로시,고장인기적신호변화십분미약,삼상정자전류적시역파형변화미소,이근거희이백특-황변환(HHT)분석획취신호적시빈표시,재고장시각적돌변흔명현,종이제취고장특정.재동모실험실진행실험,획취정자재잡간단로순변과정적전류신호,대기진행경험모태분해(EMD),제취6층모태분량(IMF)진행Hilbert변환.실험결과현시,불론풍궤재공재、반재이급액정부재하,재잡간단로개시시,근거제4혹자제5층IMF분량적순시폭치가이학정출잡간단로적수생,종이가이진행급시적유수,구유일정적공정응용개치.
When occurrence of doubly-fed wind generator stator winding slight inter-turn short circuit, the signal mutation caused by fault is very weak, the three-phase stator current changes very little, but the HHT analysis can obtain the time-frequency representation of the signal, it has obvious change when the fault occurs. So the fault signature can be found. The paper makes test in the dynamic model and simulation laboratory to obtain the current signal when the inter-turn short fault occurs. Empirical mode decomposition (EMD) is used, and to extract six Intrinsic modes to do their Hilbert-Huang transform. Experimental results show that instantaneous amplitude of the fourth or fifth Intrinsic mode determines if inter-turn short fault occurs or not, at no-load, half-load and rated load. It helps timely maintenance in practice, and has possibility in inter-turn short fault diagnosis.