A DC cable short-circuit fault is the most severe fault type that occurs in DC distribution\nnetworks, having a negative impact on transmission equipment and the stability of system operation.\nWhen a short-circuit fault occurs in a DC distribution network based on a voltage source converter\n(VSC), an in-depth analysis and characterization of the fault is of great significance to establish relay\nprotection, devise fault current limiters and realize fault location. However, research on short-circuit\nfaults in VSC-based low-voltage DC (LVDC) systems, which are greatly different from high-voltage\nDC (HVDC) systems, is currently stagnant. The existing research in this area is not conclusive, with\nfurther study required to explain findings in HVDC systems that do not fit with simulated results or\nlack thorough theoretical analyses. In this paper, faults are divided into transient- and steady-state\nfaults, and detailed formulas are provided. A more thorough and practical theoretical analysis with\nfewer errors can be used to develop protection schemes and short-circuit fault locations based on\ntransient- and steady-state analytic formulas. Compared to the classical methods, the fault analyses\nin this paper provide more accurate computed results of fault current. Thus, the fault location method\ncan rapidly evaluate the distance between the fault and converter. The analyses of error increase and\nan improved handshaking method coordinating with the proposed location method are presented.
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