{'fraction_non_alphanumeric': 0.01514059120403749, 'fraction_numerical': 0.0021629416005767843, 'mean_word_length': 5.196428571428571, '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}}
Monitoring and measurement of high‐frequency oscillatory transient recovery voltage of circuit breakers

Studying the characteristics of transient recovery voltage (TRV) becomes mandatory for selecting an appropriate circuit breaker (CB) in terms of protection and control of the power system network. A CB may fail to interrupt the short circuit faults if its rated TRV characteristic is lower than that of the power system characteristics. This paper aims to extract the net TRV waveform imposed on the breaker contacts without any prior knowledge about the system parameters. Better accuracy is achieved in the measurement of TRV parameters because the power frequency component superimposed on the raw waveform has been removed. Based on the concept of the second order generalized integrator-adaptive notch filter (SOGI-ANF), the behaviour of the TRV over time has been studied. The prominent advantage of the presented method is that it is independent from the circuit configuration and voltage and thus can be performed online on different types of power networks. The adaptive feature of the SOGI-ANF and its simple structure make it a suitable tool for analysis of TRV in power system networks. The real-time implementation of the SOGI-ANF has been obtained using an STM32F4 Discovery microcontroller board and experimental results show the effectiveness of the proposed method.