Premium
A method of mutual coupling effects of multi‐parallel routes in the presence of unbalanced faults
Author(s) -
Tanaka Kazuyuki
Publication year - 2001
Publication title -
electrical engineering in japan
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.136
H-Index - 28
eISSN - 1520-6416
pISSN - 0424-7760
DOI - 10.1002/eej.1052
Subject(s) - coupling (piping) , topology (electrical circuits) , sequence (biology) , fault (geology) , power (physics) , voltage , point (geometry) , state (computer science) , computer science , zero (linguistics) , control theory (sociology) , algorithm , engineering , physics , mathematics , electrical engineering , geometry , control (management) , mechanical engineering , linguistics , philosophy , genetics , quantum mechanics , artificial intelligence , seismology , biology , geology
The symmetrical method is even now one of the common theoretical approaches to simulating the faulted state of an electric power system, despite this method having major disadvantages, especially for unbalanced fault calculation on multi‐parallel routes due to the necessity of forming a complex equivalent zero‐sequence network. In order to protect the power system, including the multi‐parallel routes in it, from disturbance, a method that can solve the faulted state accurately and efficiently when a disturbance occurs on a multi‐parallel route is needed. From this point of view, this paper presents a newly developed fault calculation method which can easily incorporate the zero‐sequence mutual coupling effect among multi‐parallel routes without any topological changes of the symmetrical network. In the proposed method, the mutual coupling effect is treated as a voltage source inserted into each parallel branch to compensate the mutual coupling effects of other circuits. Since the voltage source can be equivalently expressed as the injection currents of the connected nodes, the faulted state can be calculated easily without topological changes of the zero‐sequence network. Numerical results for several relevant cases are presented to demonstrate the effectiveness of the method. © 2001 Scripta Technica, Electr Eng Jpn, 136(2): 9–17, 2001