Space charge measurement was performed on a 23-mm-thick cross-linked polyethylene (XLPE) cable at ambient and high temperatures using a newly developed high-sensitivity measurement device and a correction method for cables under temperature gradient. The space charge and electric field distribution were obtained with a spatial resolution of 0.5 mm (2%) at ambient and high temperatures. In addition, we propose an approach to obtain the in situ system’s impulse responses to maintain correction accuracy for long-term measurement. The reference waveforms were measured before and after 3 h of testing voltage application. It showed that sufficient time before the measurement is necessary for accurate reference waveforms. To obtain a suitable time for the measurement, the method using cross correlation was proposed.

中文翻译：

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环境和高温下 23 毫米厚 XLPE 电缆的空间电荷测量


采用新开发的高灵敏度测量装置和温度梯度下电缆校正方法，在常温和高温下对23毫米厚的交联聚乙烯（XLPE）电缆进行了空间电荷测量。在环境温度和高温下以 0.5 mm (2%) 的空间分辨率获得空间电荷和电场分布。此外，我们提出了一种获取原位系统脉冲响应的方法，以保持长期测量的校正精度。在施加测试电压3小时之前和之后测量参考波形。结果表明，测量前需要有足够的时间才能获得准确的参考波形。为了获得合适的测量时间，提出了利用互相关的方法。