定子绕组诊断的分离电压和电流正负序分量法

感应电机早期定子绕组故障表现不明显,并且受到电源和负载等外部条件的影响而难以准确检测,如瞬时功率分解法受转子转速、电流波动和电源频率影响较大;对称分量法处理定子绕组不对称问题的效果不理想;同步速坐标变换法计算复杂.为此引入了分离定子电压和电流正负序分量的方法来提取故障特征.采集到的数据先进行低通滤波处理,减弱高次谐波和噪声的影响.采用电源变换消除对负序分量来源的判断;Park 变换将信号从三维坐标转换到二维坐标中;Hilbert变换的频率相移特性可以分离信号的正负序分量.仿真结果表明:该方法可以消除其他非故障因素的影响,准确提取定子电压和电流的正负序分量,并可根据电源的不对称度,分别采用定子负序电流和负序阻抗来表征故障的严重程度.该方法解决了早期定子绕组故障检测的难题,可应用于实际工程中.

Fault Diagnosis of Induction Motor's Stator Winding by Positive and Negative Sequence Component of Voltage and Current Separation Method

Early faults of induction motors' stator winding feature is not distinct,and it is liable to the influence of power,load and other outer factors,so the accurate measurement of which is difficult.A method of positive and negative sequence component based on separation of stator voltage and current was introduced to extract the features of fault.First,the acquired data was filtered by low-pass filter to weaken the influence of high-harmonics and yawp.Power transformation could eliminate source judgment of neg...