中文摘要：

为了探讨局部放电超高频检测技术的应用,将数字化测量和超高频检测技术相结合,分析了局部放电超高频检测技术的原理。在简要介绍了局部放电超高频检测系统硬件和软件的组成后,实测并分析了检测系统的抗干扰性能。通过变电站电力变压器的现场局部放电测量,及时发现了设备的局部放电水平异常,避免了事故的发生。分析和实测表明,超高频方法较其它方法相比能有效避开电晕干扰,更易于发现设备绝缘系统早期绝缘缺陷,检测结果能准确反映设备绝缘状况,适用于电力变压器局部放电在线监测。

英文摘要：

By detecting E-M waves emitted from PD sources, the ultra-high-frequency （UHF） PD detection technique can detect and locate the PD sources inside transformers. This technique has some advantages over conventional methods, such as adjustable center frequency, selectable bandwidth and effective noise suppression. The principles of UHF PD detection technique and the detection system according to the combination of digital PD measurement and UHF PD detection, including hardware and software, were described. The anti-jamming performance was analyzed according to measurement data. PD activities of transformers were detected in substations. Experimental results show that the system can effectively detect the time and amplitude of the high-frequency and narrowband signals emitted from PD, and accurately calculate the phase resolved PD patterns and statistical operator. The analysis of measurement results proves that UHF detection technique can avoid the corona interference effectively and detect insulation defect earlier. The results reflect the real insulation conditions of power transformers. UHF detection technique is acceptable for transformers PD online monitoring.