Method of Pulling Line Selection for Single Phase Grounding Fault in Small Current Grounding System

Abstract

The present invention provides a single-phase ground fault pulling line selection method for a small current grounding system, which includes the following steps: ① inputting the pull limit electric sequence bit table; ③Set the ground fault exploration operation sequence table in the one-key sequence control program, and set the automatic sorting rules for the ground fault exploration operation sequence table; ④Set the ground fault exploration judgment in the one-key sequence control program ⑤ One-key sequence control program call; ⑥ Generate the final sequence table of ground fault exploration operation; ⑦ Automatically pull the circuit to find the ground fault line. The present invention provides a new single-phase grounding fault line selection method for small-current grounding system, which can conveniently, quickly and efficiently check out the line where single-phase grounding fault occurs in the small-current grounding system, and greatly improve the number of faulty lines. Search and incident handling efficiency.

Description

technical field [0001] The invention relates to the field of processing methods for grounding faults in distribution networks, in particular to a method for pulling and selecting lines for single-phase grounding faults in a small current grounding system. Background technique [0002] At present, most of the domestic distribution networks are small-current grounding systems, and the neutral point is not directly grounded (including the neutral point is not grounded and the neutral point is grounded through the arc suppression coil). The low-current grounding system has a very high probability of single-phase grounding faults. When a fault occurs, the symmetry of the line voltage can still be guaranteed due to the power supply, and the fault current is small, which does not affect the continuous power supply of the load. It is not necessary to cut off the power immediately under normal conditions. However, with the increasing number of distribution network feeders, the capaci...

AI Technical Summary

Problems solved by technology

[0003] The traditional single-phase grounding fault line troubleshooting method of small current grounding system is to send an order from the power supply dispatching to the monitoring personnel of the monitoring platform to try to pull the lines that may be faulty one by one. After pulling a line, see if the bus grounding telemetry signal returns If it is reset, then close the switch, the busbar grounding will act again, that is, it is determined that the line is grounded. Due to the large number of lines that need to be checked, this mode is time-consuming and labor-intensive, which makes the accident handling efficiency low and the safety risk is high.

With the advancement of technology, the current substation on-site protection measurement and control device can realize the automatic opening and closing function of the circuit breaker. The monitoring personnel can remotely control the grounding of each line through the monitoring platform to explore the soft pressure plate (realize the automatic opening and closing function of the circuit breaker) to complete the single Although the interval grounding search operation is much more convenient than the traditional method, it still needs to check the lines one by one until the grounding line is found, and the efficiency of accident handling is still low