Title |
Development of an Algorithm for Detecting High Impedance Fault in Low Voltage DC Distribution System using Accumulated Energy of Fault Current |
Authors |
Yun-Sik Oh ; Chul-Ho Noh ; Doo-Ung Kim ; Gi-Hyeon Gwon ; Joon Han ; Chul-Hwan Kim |
DOI |
http://dx.doi.org/10.5207/JIEIE.2015.29.5.071 |
Keywords |
Accumulated Energy ; EMTP ; High Impedance Fault ; LVDC Distribution System ; WSVD |
Abstract |
Recently, new Low Voltage DC (LVDC) power distribution systems have been constantly researched as uses of DC in end-user equipment are increased. As in conventional AC distribution system, High Impedance Fault (HIF) which may cause a failure of protective relay can occur in LVDC distribution system as well. It, however, is hard to be detected since change in magnitude of current due to the fault is too small to detect the fault by the protective relay using overcurrent element. In order to solve the problem, this paper presents an algorithm for detecting HIF using accumulated energy in LVDC distribution system. Wavelet Singular Value Decomposition (WSVD) is used to extract abnormal high frequency components from fault current and accumulated energy of high frequency components is considered as the element to detect the fault. LVDC distribution system including AC/DC and DC/DC converter is modeled to verify the proposed algorithm using ElectroMagnetic Transient Program (EMTP) software. Simulation results considering various conditions show that the proposed algorithm can be utilized to effectively detect HIF. |