电机局部放电超声特性

Ultrasonic characteristics of motor partial discharge

为探索电机局部放电检测新方法,分析电机局部放电机理和国内外对电机局部放电监测研究状况,提出利用超声法对电机局部放电进行监测。为此,构建电机定子绕组存在的几种典型局部放电模型和实验硬件系统,并进行放电实验。在局部放电实验室,采用一种窄带超声传感器对几种典型局部放电超声信号进行采集。对相同条件下采集到的各种模型局部放电超声信号特性进行分析和比较。实验结果分析表明,不同类型的局部放电,无论其超声信号波形还是频谱特征均存在差异。因此,可以对电机局部放电超声信号进行特征提取,为实现基于超声法的电机放电故障模式识别奠定了基础。

In order to explore a new measurement method of partial discharge （PD） for motor, the electrical mechanism of PD and the situation of PD monitoring were discussed. An approach using ultrasonic for monitoring PD in a motor was proposed. Then several typical PD models of motor windings were construc- ted, and the PD monitoring system was developed. In the PD laboratory, four narrow-band ultrasonic sensors were used to detect the ultrasonic of the typical PD models. And under the same experiment conditions, the characteristics of the ultrasonic of the typical PD models were analyzed and compared. Exper- imental results show that the waveform or spectral characteristics of ultrasonic signals are different among the different types of PD. Therefore, the PD features of the motor can be extracted based on ultrasonic, and then the preparatory work for pattern recognition research has been completed.