Open Access

ARTICLE

Partitioning Calculation Method of Short-Circuit Current for High Proportion DG Access to Distribution Network

Wei Wang¹, Qingzhu Shao¹, Shaoliang Wang^2,*, Yiwei Zhao², Yuanbo Ye¹, Duanchao Li¹, Mengyu Wu²
1 Anhui Electric Power Dispatch and Control Center, State Grid Anhui Electric Power Co., Ltd., Hefei, 230000, China
2 School of Electrical Engineering, Beijing Jiaotong University, Beijing, 100000, China
* Corresponding Author: Shaoliang Wang. Email:

Energy Engineering https://doi.org/10.32604/ee.2024.051409

Received 05 March 2024; Accepted 25 June 2024; Published online 26 July 2024

Abstract

Aiming at the problem that the traditional short-circuit current calculation method is not applicable to Distributed Generation (DG) accessing the distribution network, the paper proposes a short-circuit current partitioning calculation method considering the degree of voltage drop at the grid-connected point of DG. Firstly, the output characteristics of DG in the process of low voltage ride through are analyzed, and the equivalent output model of DG in the fault state is obtained. Secondly, by studying the network voltage distribution law after fault in distribution networks under different DG penetration rates, the degree of voltage drop at the grid-connected point of DG is used as a partition index to partition the distribution network. Then, iterative computation is performed within each partition, and data are transferred between partitions through split nodes to realize the fast partition calculation of short-circuit current for high proportion DG access to distribution network, which solves the problems of long iteration time and large calculation error of traditional short-circuit current. Finally, a 62-node real distribution network model containing a high proportion of DG access is constructed on MATLAB/Simulink, and the simulation verifies the effectiveness of the short-circuit current partitioning calculation method proposed in the paper, and its calculation speed is improved by 48.35% compared with the global iteration method.

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Keywords

High proportion DG; short-circuit calculation; low voltage ride through; partition iteration

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