数字工厂研究室知识库

鼠笼电机起动暂态破坏了电机电流信号特征分析(MCSA)方法的使用条件,导致该方法无法诊断出起动运行状态下的转子断条故障。针对这一问题,提出鼠笼电机早期转子断条故障Wigner-Ville分布诊断方法。首先,利用离散小波变换对三相定子电流Park矢量模平方信号预处理,借以消除谐波干扰和交叉项影响,然后通过Wigner-Ville分布描述故障特征谐波的能量-滑差变化趋势,并结合其能量测度判断转子断条故障发生与否。在3 kW电机实验台上对所提出的方法进行实验验证,实验结果证实了所提方法的有效性。

Motor current signature analysis ( MCSA) fails to detect broken rotor bars in an induction motor，due to the fact that assumption of steady-state becomes unavailable during start-up transient. The diagnosis techniques based on Wigner-Ville distribution ( WVD) is proposed to resolve the problem． Firstly，preprocessing for square phase-3 stator current Park's vector modulus signal was completed by discrete wavelet transform ( DWT) for the purpose of eliminating harmonic disturbance and restraining cross-term which prevents diagnosis effectiveness. Then，WVD was conducted on the obtained square Park's vector modulus signal. And combining with the evolution of energy-slip curve characteristic pattern and the WVD energy measurement during start-up transient， it is judged if the broken rotor bar defect occurs. The experiment verification was performed on a 3 kW motor experiment test bench. Test results of induction machines operating during start-up transient show the ability of the presented method to detect broken rotor bars.