Requirement
The customer wished to be able to create and exploit an ETAP model of his LV (28V) DC network so as to study the electrical behavior in steady network conditions as well as during short-circuits.
CAPSIM was therefore requested for this mission for its expertise and knowledge of networks under strong technical and regulatory constraints (civilian and military nuclear, offshore rigs, complex scientific equipment, etc...) and its knowledge regarding electrical calculation tools.
Realization
A model of a part of the network has been realized with ETAP in considering the specificities of equipment in low voltage.
Selectivity Curve
The study of the electrical network was then done :
- Voltage plan study : the use of a Load flow calculation on a numerical model instead of a pure analytic method allows taking into account the real load behavior linked to voltage conditions. Consequently, results are more accurate.
- Power flow study – equipment steady state withstand. As for previous topic, using a numerical model allows to simulate realistically current consumption linked to voltage conditions. Moreover, we were able to simulate various sources and load scenarios.
- Short-circuit current calculations :Maximum and minimum short-circuit current were calculated on the entire network according to IEEE 946-2004 and IEC 61660-1 standards.
- Protection strategy : This study was realized thanks to protection coordination graphs. It allowed checking that the protective device breaking time (fuses in this case) was short enough to ensure protection, and that protection coordination principles were respected.
Results
With the presence of a complete range of equipment, the realization of this preliminary study allowed the client to ensure the usage feasibility of his ETAP software for the realization of several study types on his low voltage DC network.
Following this preliminary analysis, a study is currently being performed on the LV DC network of the client.
A part of the ETAP model
