Open AccessImproved high‐speed de‐excitation system for brushless synchronous machines tested on a 20 MVA hydro‐generator
Author(s) -
Rebollo Emilio,
Blanquez Francisco R.,
Platero Carlos A.,
Blazquez Francisco,
Redondo Marta
Publication year - 2015
Publication title -
iet electric power applications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.815
H-Index - 97
eISSN - 1751-8679
pISSN - 1751-8660
DOI - 10.1049/iet-epa.2014.0313
Subject(s) - excitation , resistor , generator (circuit theory) , permanent magnet synchronous generator , synchronous motor , control theory (sociology) , computer science , electric generator , field coil , engineering , electrical engineering , rotor (electric) , magnet , voltage , power (physics) , physics , control (management) , quantum mechanics , artificial intelligence
Synchronous machines with brushless excitation have the disadvantage that the field winding is not accessible for the de‐excitation of the machine. This means that, despite the proper operation of the protection system, the slow de‐excitation time constant may produce severe damage in the event of an internal short circuit. A high‐speed de‐excitation system for these machines was developed, and this study presents the continuation of a previously published study. This study presents the design by computer simulation and the results of the first commissioning of this de‐excitation system in a commercial 20 MVA hydro‐generator. The de‐excitation is achieved by inserting resistance in the field circuit, obtaining a dynamic response similar to that achieved in machines with static excitation. In this case, a non‐linear discharge resistor was used, making the dynamic response even better.