Application of frequency mixing technique to ultra-high-frequency PD detection for transformers

作者：Wang Guo Li^*; Hao Yan Peng; Yuan Peng; Li Yan Ming

来源：Proceedings of the CSEE, 2004, 24(10): 115-120.

• Frequency mixing technique
• Partial discharge detection
• Power transformer
• Ultrahigh frequency

A new method, i.e., frequency mixing technique, was proposed to extract ultra-high-frequency (UHF) PD signals in this paper. By using this method, simulation studies were made to process UHF PD signals. Results showed that this method not only kept the peak value and phase characteristics, but also reduced the frequency of UHF PD signals. Based on frequency mixing technique, an on-line UHF PD monitoring system was developed for transformers. With this system, some typical PD models were detected. Experimental results showed that the technique can effectively detect the time and the amplitude of the high-frequency (adjustable center frequency between 400-800 MHz in minimum steps of 5 MHz) and narrowband (10, 20, 40 or 80 MHz) signals emitted from PD, calculate accurately phase resolved PD patterns and statistical operators, suppress effectively interference from background, and be useful for on-line monitoring and intelligent diagnosis of UHF PD in transformers.

• 出版日期2004
• 单位清华大学