RT Journal Article
A1 Mahdi Ghotbi Maleki
A1 Reza Mohammadi Chabanloo
A1 Hamid Javadi

PB iet
T1 Method to resolve false trip of non-directional overcurrent relays in radial networks equipped with distributed generators
JN IET Generation, Transmission & Distribution
VO 13
IS 4
SP 485
OP 494
AB The connection of distributed generation sources to the distribution network has negative effects on the network protection such as; a false trip of non-directional overcurrent relays. In this study, an offline method is proposed to overcome the false trip issue. In this method, the false trip is modelled as a new set of coordination constraints in the optimal coordination problem. For establishing false trip constraints, pickup current setting and characteristic type of relays are selected in addition to the time multiplier setting. Considering false trip constraints in the coordination problem increases the operating time of relays. Therefore, the optimisation is applied to obtain the settings of non-directional overcurrent relays in order to reduce their operating times in addition to resolving the false trip. Also, three new approaches are defined for pickup current selection based on pickup current range. A combination of genetic algorithm and linear programming technique is used to access optimised responses. Finally, the proposed method is implemented on a sample radial distribution network and the results demonstrated that the occurrence of the false trip was prevented and also the operating time of the relays was reduced to an acceptable level.
K1 sample radial distribution network
K1 nondirectional overcurrent relays
K1 distributed generation sources
K1 operating time
K1 false trip issue
K1 false trip constraints
DO https://doi.org/10.1049/iet-gtd.2018.5610
UL https://digital-library.theiet.org/;jsessionid=98eprebo2sqob.x-iet-live-01content/journals/10.1049/iet-gtd.2018.5610
LA English
SN 1751-8687
YR 2019
OL EN