Mobile QR Code QR CODE : The Transactions of the Korean Institute of Electrical Engineers
Title Analysis on Operation Characteristics of OCR Using Impedance Compensation Algorithm Considering Application of SFCL in a Power Distribution System
Authors 조유정(Yoo-Jung Cho) ; 박민기(Min-Ki Park) ; 임성훈(Sung-Hun Lim)
DOI https://doi.org/10.5370/KIEE.2021.70.11.1670
Page pp.1670-1676
ISSN 1975-8359
Keywords Fault current; Impedance compensation method; Over-current relay (OCR); Superconducting fault current limiter (SFCL).
Abstract Recently, as the interest in renewable energy has increased and the electric power industry has developed, the distributed power generation has increased and the fault current has increased. This situation can cause the over-current which exceeds the capacity of the circuit breaker, it may lead to accidents in a power system, so it needs to replace in a larger capacity circuit breaker or to reduce the fault current. Installing a superconducting fault current limiter (SFCL) is an effective way to limit the fault current, though the trip delay of the over-current relay(OCR) occurs, also affects the protection coordination between OCRs. The correction method using the voltage component of SFCL was carried out as a previous study on this problem. However, this method is complicated because the correction factor should be changed according to the system condition. In this paper, an impedance compensation method is proposed to effectively exclude the effect of SFCL on the OCR. Unlike the correction method using the voltage component previously studied, the bus voltage was reflected, and the relay elements were calculated as impedance using this to reconstruct the characteristic equation of the OCR to decrease the influence of the SFCL. In addition, for precise correction, the impedance is divided into resistance/reactance components and compared with previous method. The results are analyzed through simulation using PSCAD/EMTDC.