A novel voltage sag approach during unintentional islanding scenarios: A survey from real recorded events

Alexandre Serrano-Fontova, P. Casals-Torrens and R. Bosch



In this paper, a new voltage sag approach is analytically modelled and validated using both simulation and field measurements. The main aspect of this approach is to propose a new voltage sag feature which appears during unintentional islanding operations (IOs). The unintentional IO occurs when an induction motor is removed from the main utility following a circuit breaker (CB) clearing, transiently, the induction motors (IMs) are acting as generators maintaining the affected distribution feeder with voltage until it is reconnected. The voltage sag modelled in the current article follows an exponential form, as a matter of fact, here it will be demonstrated that the proposed model reaches satisfactorily the field measurements and evidences the dependability of the model adopted. Furthermore, it is worthwhile to note that this novel power quality (PQ) event has not been investigated yet and enhances voltage sag studies. Lastly, it is crucial to point out that all recorded events and a large amount of data needed so as to validate this transient, has been measured in a distribution network (DN) located in Spain.

Published in: Renewable Energy & Power Quality Journal (RE&PQJ, Nº. 17)
Pages: 43-48 Date of Publication: 2019/07/15
ISSN: 2172-038X Date of Current Version:2019/04/10
REF: 215-19 Issue Date: July 2019
DOI:10.24084/repqj17.215 Publisher: EA4EPQ

Authors and affiliations

Alexandre Serrano-Fontova1, 2, P. Casals-Torrens1 and R. Bosch1
1. Department of Electrical Engineering. E.T.S.E.I.B, Polytechnic University of Catalonia. Barcelona (Spain)
2. Electrica Serosense Distribuidora. Pol. Ind. Panamà. Torres de Segre (Spain)

Key words

Power quality, islanding operations, voltage sags, distribution networks.


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