Title :
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
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;
Conference_Titel :
Electronics and Application Conference and Exposition (PEAC), 2014 International
Conference_Location :
Shanghai
DOI :
10.1109/PEAC.2014.7037883
