A short-circuit current calculation method for low-voltage DC microgrid

Author

Xiaoli Lai ; Fei Liu ; Kai Deng ; Qi Gao ; Xiaoming Zha

Author_Institution

Sch. of Electr. Eng., Wuhan Univ., Wuhan, China

fYear

2014

fDate

5-8 Nov. 2014

Firstpage

365

Lastpage

371

Abstract

Short-circuiting in dc lines affects the security and reliability of dc microgrid greatly. A short-circuit current calculation method for low-voltage dc microgrid is proposed in this paper. To solve the calculation of short-circuit current, a line model of bipolar which includes π type equivalent circuits, solid-state bidirectional switches with snubber circuits and freewheeling branches is adopted. The line current under different short-circuit fault types in dc bus is discussed and the circuit working mechanisms before and after solid-state switches action are analyzed, and then the analytic expressions of the line fault current are derived. Besides, the freewheeling loop of the short-circuit current is also analyzed after the removal of fault. The correctness of the analytic expressions is verified by MATLAB/Simulink simulations.

Keywords

distributed power generation; power generation faults; power generation reliability; short-circuit currents; snubbers; switchgear; π-type equivalent circuits; DC lines; Matlab-Simulink simulations; bipolar line model; freewheeling branches; freewheeling loop; line fault current; low-voltage DC microgrid reliability; low-voltage DC microgrid security; short-circuit current calculation method; short-circuit fault types; snubber circuits; solid-state bidirectional switches; Circuit faults; Equivalent circuits; Fault currents; Microgrids; Short-circuit currents; Snubbers; Switches; DC microgrid; dc line; freewheeling loop; short-circuit;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronics and Application Conference and Exposition (PEAC), 2014 International

Conference_Location

Shanghai

Type

conf

DOI

10.1109/PEAC.2014.7037883

Filename

7037883