某小功率永磁无刷直流电机噪声试验研究

Research on Noise Problem for A Low Power Permanent Magnet Brushless DC Motor

某小功率直流无刷永磁电机在工作过程中振动明显,噪声较大。为研究电机噪声的产生原因,在半消声室内对自由状态下的电机单体进行转速扫频试验,分析得到近场噪声的频谱特征,并结合输入电流、壳体表面振动频谱结果,以及电机结构模态试验结果,得出电机噪声问题的产生原因是转动部件动不平衡、电机结构导致的轴向振动与结构共振以及轴承早期磨损等,为电机NVH性能优化奠定了基础。

A low power permanent magnet brushless DC motor shew noise and vibration problems during working. To study the mechanism of motor noise problem, sweep measurement was performed for a single motor under free state in semi-anechoic room. The near-field time-frequency characteristics were analyzed. Combined with input current, housing vibration spectrum results and motor structure modal test results, it was concluded that the root causes of motor noise were dynamic unbalance of rotating components, axial vibration and structural resonance induced by motor structure, and bearing early worn. This research laid the foundation of optimization of motor NVH performance.