A Novel Machine Learning-Based Short-Circuit Current Prediction Method for Active Distribution Networks

Zheng Zheng,Jiang Jiang,He He,Wang Wang

doi:10.3390/en12193793

Abstract

The traditional mechanism models used in short-circuit current calculations have shortcomings in terms of accuracy and speed for distribution systems with inverter-interfaced distributed generators (IIDGs). Faced with this issue, this paper proposes a novel data-driven short-circuit current prediction method for active distribution systems. This method can be used to accurately predict the short-circuit current flowing through a specified measurement point when a fault occurs at any position in the distribution network. By analyzing the features related to the short-circuit current in active distribution networks, feature combination is introduced to reflect the short-circuit current. Specifically, the short-circuit current where IIDGs are not connected into the system is treated as the key feature. The accuracy and efficiency of the proposed method are verified using the IEEE 34-node test system. The requirement of the sample sizes for distribution systems of different scale is further analyzed by using the additional IEEE 13-node and 69-node test systems. The applicability of the proposed method in large-scale distribution network with high penetration of IIDGs is verified as well.

Highlights

Power inverters are commonly used to interface distributed generators (DGs) with distribution systems
Due to the strong nonlinear characteristics of inverter-interfaced distributed generators (IIDGs), the short-circuit current of IIDGs is significantly different from traditional generators [1], which is typically smaller than two times the rated current
A novel data-driven method for calculating short-circuit current in active distribution networks based on XGBoost is proposed

Summary

Introduction

Power inverters are commonly used to interface distributed generators (DGs) with distribution systems. Due to the strong nonlinear characteristics of inverter-interfaced distributed generators (IIDGs), the short-circuit current of IIDGs is significantly different from traditional generators [1], which is typically smaller than two times the rated current. In the case where the penetration of IIDGs in the distribution system is not high, the traditional symmetrical component method can still be used to calculate the short-circuit current, where the IIDGs are assumed to be disconnected from the grid when fault occurs. With the continuous increase of IIDG penetration, it is difficult to meet the application requirements, due to the increasing calculation errors of short-circuit current. The demand for the accurate and efficient short-circuit current calculation method in a distribution system with high penetration of IIDGs is becoming increasingly urgent.

Methods

Results

Conclusion