Back-up short circuit protection in underground medium voltage networks
Journal Title: Mining – Informatics, Automation and Electrical Engineering - Year 2015, Vol 523, Issue 3
Abstract
The paper presents issues related to the implementation of back-up short-circuit protection in the final sections of an underground medium voltage distribution network. The difficulties may arise from regulatory requirements regarding the operation time of protection devices in potentially explosive areas and relatively low values of short-circuit currents compared with load currents. Sample calculations results have been presented to illustrate the problems of selecting current settings of short-circuit protection. A method to overcome these problems by using transformer stations with a circuit breaker on the primary side has been shown.
Authors and Affiliations
Sergiusz Boron, Jarosław JOOSTBERENS
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