Open AccessAnalysis of DC offset in fault current caused by machines in a medium voltage distribution network
Author(s) -
Bashar Erfan,
Han Qin,
Wu Ruizhu,
Ran Li,
Alatise Olayiwola,
Jupe Samuel
Publication year - 2019
Publication title -
the journal of engineering
Language(s) - English
Resource type - Journals
ISSN - 2051-3305
DOI - 10.1049/joe.2018.8221
Subject(s) - offset (computer science) , thyristor , fault current limiter , control theory (sociology) , fault (geology) , voltage , computer science , current (fluid) , zero crossing , dc bias , electrical engineering , engineering , physics , electric power system , power (physics) , control (management) , quantum mechanics , artificial intelligence , seismology , geology , programming language
This study presents a study on the time when the short‐circuit fault current in an MV distribution network will cross the zero point in the presence of DC offset affected by the local synchronous and/or induction machines. The motivation of the study is to examine using thyristors to bypass a series compensator in the network while the subsequent turning‐off of the thyristors depends on the zero‐crossing of the current. One of the main uncertainties is the DC offset in the fault current due to the machines connected locally, which may defer the thyristor turning‐off. This possibility has been examined in this study and the results demonstrate the parameters of the machines that have most influence on the time when the fault current will pass the zero point. It is shown that machines with higher unit ratings usually cause more delays in comparison with smaller units.