摘要:
A method for detecting and locating faulty line on the distribution network circuit based on full waveform information, which uses the current data on the fault occurrence and whole-process operation of the compensation device to effectively solve such common problems as low fault current, poor reliability and low sensitivity in case of single-phase grounding fault to the low-current system through precise GPS synchronization. It improves the sensitivity and reliability of the grounding fault detection, which does not interfere with the system and is applicable to high-resistance grounding.
摘要:
A parallel connection method and a device for multi-channel partial discharge (PD) signals have input sources of pre-processed and amplified signals received by multiple PD sensors. Then isolation and processing are provided to the signals to ensure that each signal is able to be self-triggered and unidirectional transmitted. Finally, processed signals of each channel are outputted. For ultra-high frequency (UHF) PD signal, the delay transmission is realized by a surface acoustic wave (SAW) delay line method. The present invention makes the amplified multi-channel PD signals self-trigger and unidirectional transmit though isolation processing and then realizes parallel connection without interference. The method also decreases signal transmission loss. Meanwhile, all the detected PD signals transmit on one signal bus through parallel connection method, so as to use only one set of acquisition unit to monitor and acquire the signals received by multiple sensors, which obviously lowers the system cost.
摘要:
A method for identifying a lightning fault of an overhead transmission line (OTL) comprising determining a polarity of a travelling wave of each of three ABC phases subsequent to a single phase outage of the OTL. If the polarity of each phase is the same, the outage is a lightning fault and its type a back flashover; if not the same, proceed to the second step to determine a current change rate R of the fault phase. If R is larger than a threshold value, the outage is a lightning fault and its type a shielding failure; otherwise, the outage is a single-phase grounding fault. A system for identifying the lightning fault which comprises successively at least a group of fault detectors, a wireless communication module, a remote monitoring master station which adopts the above method to determine the fault type of the overhead transmission line.
摘要:
A parallel connection method and a device for multi-channel partial discharge (PD) signals have input sources of pre-processed and amplified signals received by multiple PD sensors. Then isolation and processing are provided to the signals to ensure that each signal is able to be self-triggered and unidirectional transmitted. Finally, processed signals of each channel are outputted. For ultra-high frequency (UHF) PD signal, the delay transmission is realized by a surface acoustic wave (SAW) delay line method. The present invention makes the amplified multi-channel PD signals self-trigger and unidirectional transmit though isolation processing and then realizes parallel connection without interference. The method also decreases signal transmission loss. Meanwhile, all the detected PD signals transmit on one signal bus through parallel connection method, so as to use only one set of acquisition unit to monitor and acquire the signals received by multiple sensors, which obviously lowers the system cost.