Data-driven single-phase earth fault line selection method based on pre-fault and post-fault steady-state variable quantity information

Abstract

The invention provides a data-driven single-phase earth fault line selection method based on pre-fault and post-fault steady-state variable quantity information The method is divided into an offline training part and an online application part, and comprises the following steps of: firstly, acquiring topological information and network parameters of a target power distribution network, and establishing a corresponding model in simulation software; secondly, simulating to obtain a sufficient sample data set by taking pre-fault and post-fault steady-state current effective value variable quantity and interconnection switch state combination as characteristics and taking a fault line number as a label, training a line selection model by utilizing a machine learning method, and testing to obtain a network error-prone line selection region; and finally, inputting sample characteristics obtained by an actual power distribution network into an offline trained model, outputting a line selection result and confidence, comparing the line selection result and confidence with the error-prone line selection region, and giving a prompt if the line selection result belongs to the error-prone line region. According to the method, accurate line selection can be achieved for the single-phase earth fault of a neutral point ungrounded power distribution network, and high line selection accuracy is still achieved under the condition that the fault is grounded through high resistance.

Description

technical field [0001] The invention belongs to the field of power systems, in particular to a data-driven single-phase grounding fault line selection method based on steady-state change information before and after a fault, and is suitable for a neutral point ungrounded distribution network. Background technique [0002] In order to ensure the reliability of power supply in the distribution network, when the capacitive current of the whole system does not exceed a certain value, the neutral point is not grounded. When a single-phase ground fault occurs in the neutral point ungrounded distribution network, the fault current is small, and the current protection will not operate, which provides time for troubleshooting, but also causes difficulties in fault line selection, especially when the fault point touches tree branches , sand, asphalt, cement and other non-ideal media, a high-resistance ground fault is formed, which further increases the difficulty of line selection for...

AI Technical Summary

Problems solved by technology

The third type of method can perform better than the first two types due to the combination of the advantages of the method and the number of samples, but the complexity of the process and the demand for high-precision measurement equipment such as PMU greatly increase the application requirements. threshold

Images