{'fraction_non_alphanumeric': 0.024096385542168676, 'fraction_numerical': 0.025100401606425703, 'mean_word_length': 5.006024096385542, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
The characteristics of ultra-wideband partial discharge of insulation in aging process

The characteristics of the partial discharge (PD) in the aging process of insulation are studied in an ultra-wideband range from 0 to 500 MHz in this paper. The electrical or thermal aging of epoxy samples involving cavities with cone-cone electrode or needle-plate electrode systems are conducted. A TE571 PD detector is used to distinguish the discharge classification, and an ultra-wideband PD detecting system is employed for detecting ultra-wideband PD characteristics of insulation in aging process. The experimental results show that the major characteristic peaks of these insulation samples locate in the frequency ranges of such as 0/spl sim/75 MHz, 150/spl sim/200 MHz. In addition, the discharge characteristics of stator bar insulation samples of a 300 MW turbo-generator out of service is also measured, indicating that characteristic peaks locate in the frequency range of 100/spl sim/125 MHz.