Low-current grounding intelligent route selection method and apparatus

Abstract

A low current grounding intelligent route selecting method comprises: firstly judging whether the grounding fault happens or not; then acquiring the zero sequence current data before or after the fault to judge the route selecting. The steps for processing the obtained current data by sampling comprise: selecting the appropriate wavelet function; performing the wavelet decomposition for the fault signal; selecting the decomposition dimension with the maximum value as the characteristic dimension information of the fault; performing the wavelet reconstruction for the characteristic dimension information; judging the fault line. The apparatus for implementing the method comprises an event management module, a data processing module, a data acquiring module, a data communication module, a power supply module, a display and control module and a CAN communication module; the power supply module is connected with each module for supplying power; the output signal of the data acquiring module is transferred to the data processing module, the data processing module is connected with the event management module to perform the data communication; the event management module output is connected with the display and control module and the CAN communication module. The invention solves the problems existing in the prior art.

Description

Technical field: [0001] The invention belongs to the field of relay protection, in particular to a small current grounding intelligent line selection method and device for single-phase grounding faults in a small current grounding system. Background technique: [0002] my country's medium-voltage distribution network generally adopts the method of not grounding or grounding through arc suppression coils, which is what we call a small current grounding system. When a small-current grounding fault occurs, the symmetry of the system voltage is not destroyed and the current value is small, so the relevant regulations stipulate that the small-current grounding system can continue to run for 1 to 2 hours when a single-phase grounding fault occurs. However, since the voltage of the non-faulted phase rises to the line voltage when a fault occurs, long-term operation will cause single-phase grounding to become a multi-point short circuit. Moreover, when an arc is grounded, it will c...

AI Technical Summary

Problems solved by technology

With the development of distribution network, the structure of distribution network is becoming more and more complex, and the method of line selection based on fault steady-state information can no longer meet the requirements of power supply reliability.

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