简要说明感应电机的几点故障诊断方法

简要说明感应电机的几点故障诊断方法 船舶感应电机常见故障分为 轴承故障 定子故障 转子 故障 气隙偏心故障等等 如果电机的通风状况良好 同 时考虑环境温度对电机的影响 温度的测量可以采用基 于热模式或者定子电阻的模式 基于空间静电荷的建立 现象 利用热梯度 thermalstepmethod tsm 来监视定子 绕组绝缘的老化现象 同时测量反映能量级别的热激励 泄放电流 thermally stimulated discharg currents tsdo 通过将 tsm 和 tsdc 结合在一起 可以预报定子绕 组的绝缘寿命 对于低压感应电机 通过采用非破坏性 的诊断设备如塑料光纤 plasticopticalfiber pof 来评测绝 缘层的老化 该方法是通过对两个不同的红外波长上的 反射吸光率变化来进行评测的 The induction motor fault is divided into bearing fault rotor stator fault fault air gap eccentric fault and so on if the ventilation motor is good considering the effect of environmental temperature on the motor temperature measurement using thermal model or the model based on the stator resistance The phenomenon of static charge based on the established space using thermal gradient thermalstepmethod TSM to monitor the aging of stator winding insulation simultaneous measurement of reflected thermal excitation energy level of the drain current thermally stimulated discharg currents tsdo the TSM and TSDC together can forecast the stator winding insulation life For low voltage induction motor through the use of diagnostic equipment non destructive such as plastic optical fiber plasticopticalfiber POF to the aging of insulating layer evaluation the method is based on the reflection of two different infrared wavelength absorbance change for evaluation 2 振动诊断方法 2 vibration diagnosis method 电机定子的振动是定子绕组匝间短路 单向运 行 欠压运行等的函数 在电磁力矩和定子之间的谐振 是引起电机噪声的主要原因 The vibration motor is stator winding inter turn short circuit one way operation less function pressure operation the resonance between the electromagnetic torque and stator is mainly caused by the noise of motor 2 1 定子异常产生的电磁振动 电机运行时 转 子在定子内腔旋转 由于定 转子磁场的相互作用 定 子机座将受到一个旋转力波的作用 而发生周期性的变 形并产生振动 定子电磁振动的特征振动频率为电源频 率的 2 倍 Electromagnetic vibration motor running 2 1 generated by the stator rotor rotating in the cavity of the stator the rotor magnetic field interaction the stator will be subject to a rotational force wave deformation of periodic and vibration Characteristics of vibration frequency of stator vibration is 2 times of the power frequency 2 2 气隙偏心引起的电磁振动 气隙偏心有两 种情况 一种静态偏心 另一种是动态偏心 静态偏心 是由于电动机定子中心与转子轴心不重合造成的 而气 隙偏心是由转轴挠曲或酱油转子铁心不圆造成的 这两 种偏心都能引起电磁振动 但是振动的特征并不完全相 同 静态气隙偏心的电磁振动频率是电源频率的 2 倍 而动态气隙偏心的振动频率在转子转速频率和旋转磁 场同步转速频率都可能出现 Electromagnetic vibration air gap eccentric air gap eccentricity of 2 2 there are two a static eccentricity another is dynamic eccentricity Static eccentricity is the result of motor stator and rotor axis does not coincide with the center of the And the air gap eccentricity is caused by shaft deflection or the rotor core is not round The two eccentric can cause electromagnetic vibration but vibration characteristic is not exactly the same Electromagnetic vibration frequency static air gap eccentricity is 2 times of the power frequency and the vibration frequency of the dynamic air gap eccentricity in the rotor speed frequency and rotating magnetic synchronous speed frequency may appear 2 3 转子导体异常引起的电磁振动 鼠笼型感 应电机因笼条断裂 膨润土防水毯将产生不平衡的电磁 力 其性质和转子动态偏心的情况相同 它引起的电磁 振动也和转子动态偏心相似 较难辨识 Cause abnormal 2 3 rotor conductors electromagnetic vibration of squirrel cage induction motor with broken bar the unbalanced electromagnetic force will produce its nature and rotor dynamic eccentricity of the same electromagnetic vibration induced by it are similar and rotor dynamic eccentricity difficult identification 2 4 转子不平衡产生的机械振动 电机转子质 量分布不均匀时 产生了重心位移 不平衡质量在旋转 时将产生单边离心力 引起了变化的支承力 电机运行 变得不稳定了 由转子不平衡造成的机械性振动频率和 转速频率相等 2 4 rotor unbalance mechanical vibration generated by the motor rotor mass distribution is not uniform the displacement of center of gravity uneven quality will have a single centrifugal force when rotating caused the supporting force changes motor operation becomes unstable By the rotor unbalance caused by mechanical vibration frequency and speed of frequency equal to 2 5 轴承异常产生的机械振动 由于电机滚动 轴承损坏 设计制造中误差 在运行中将会出现机械振 动 每种规格的滚动轴承 泰安道闸都有其一定的特征 频率 而滑动轴承的振动特征频率略低于转子回转频率 的一半 通常为 0 42 0 48 2 5 bearing abnormal mechanical vibration generated by the motor rolling bearing damage due to error in design and manufacturing in the operation will be a me