In this paper, a few combinations of PD sources that occur in stator insulation are studied at variable excitation frequencies in the range of (50-0.1) Hz. These combinations tend to complicate the identification of PD sources at power frequency PD measurements, whereas PD measurement at variable excitation frequency for the same combinations has shown positive results. PRPD pattern, pulse phase distribution and PD parameters like peak apparent charge magnitude, integrated charge per cycle and the ratio of positive and negative integrated charge per cycle are used for analysis. From the studies carried out on 6.6 kV rated stator coils, results obtained indicate that PD measurements at variable excitation frequency are helpful in PD source identification when multiple PD sources are active.

中文翻译：

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使用变频励磁识别定子绝缘中同时激活的局部放电源


本文研究了在 (50-0.1) Hz 范围内的可变激励频率下发生在定子绝缘中的几种局部放电源的组合。这些组合往往会使工频局部放电测量中局部放电源的识别变得复杂，而相同组合的可变激励频率下的局部放电测量已显示出积极的结果。 PRPD 模式、脉冲相位分布和 PD 参数（如峰值表观电荷幅度、每周期积分电荷以及每周期正负积分电荷比率）用于分析。对 6.6 kV 额定定子线圈进行的研究表明，当多个局部放电源处于活动状态时，可变励磁频率下的局部放电测量有助于识别局部放电源。