Paper Info
Title
Analytical Calculation of Transient Short-Circuit Currents for MMC-Based MTDC Grids
Abstract
DC short-circuit current calculation is necessary to design and protect modular multilevel converter-based (MMC-based) multiterminal dc (MTDC) grids. In this article, a general and analytical short-circuit current calculation method is proposed for bipolar MTDC grids. For pole-to-pole (P2P) faults, the superposed fault equivalent network of the MTDC grid is first developed in the frequency-domain. Then, a decoupling method based on the network inductance ratio is proposed, which simplifies the high-order network into the superposition of several independent two-order <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">RLC</i> circuits. As a result, the short-circuit current can be expressed as the sum of the currents of these <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">RLC</i> circuits. For pole-to-ground (P2G) faults, the phase-domain dc line impedance considering the coupling effects is determined based on its modal-domain parameters, so that the P2G fault current can be calculated using the method of the P2P fault. The proposed method’s effectiveness is verified through simulations and experiments, and the calculation error is classified and analyzed. Compared with the existing methods, the proposed method is more accessible, more accurate, and available for hand-solution.
Year
DOI
Venue
2022
10.1109/TIE.2021.3099235
IEEE Transactions on Industrial Electronics
Keywords
DocType
Volume
Fault current calculation,multiterminal dc (MTDC) grids,network decoupling,pole-to-ground (P2G) fault,pole-to-pole (P2P) fault
Journal
69
Issue
ISSN
Citations 
7
0278-0046
1
PageRank 
References 
Authors
0.39
0
7
Name
Order
Citations
PageRank
Yiping Luo110.72
Jinghan He220.77
Meng Li342.48
Dahai Zhang410.39
Yongjie Zhang510.72
Yuanwei Song610.39
Ming Nie710.39