electrodynamic forces on busbars
Posted: 23 Apr 2024, 12:02
Hi,
in case of short-circuit inside or downstream an electrical cabinet (supplied from a low voltage 50/60 Hz grid), the electrodynamic forces amongst the conductors inside the cabinets can be relatively high.
Here is an example of a paper that deals with this subject:
https://www.studiecd.dk/cahiers_techniq ... ystems.pdf
Is there a way to estimate with elmer:
1. the short-circuit currents (these could be computed with other means and given as an input to elmer)
2. the electrodynamic forces generated by the short-circuit currents
3. the deformation of the busbars during the event
4. the forces acting on the busbars supports (isolators, metal brackets...)
5. during the event, the temperature of the busbars can raise by let's say 100-200 K:
5a) can elmer estimate the power losses and temperature rises of the busbars during the short-circuit event?
5b) the temperature increase can change the mechanical properties of the busbars. Can this be taken in account by the solver?
While the currents can be assumed to be independent on what happens inside the cabinet, the electrodynamic forces depend on the distance between the conductors and thus on their deformations. So forces and defomations of the conductors are a coupled problem. (if deformations are small compared to the distances amongst the conductors, than the deformations can be neglected for the sake of calculation of the electrodynamic forces).
Point 5 of the previous list goes into another level and could be neglected. Alternatively, the busbar temperature rise could be estimated in other ways, knowing the current and the resistivity of the conductors.
Has anyone had any experience with elmer on this kind of problems?
Are there any example available?
Thanks,
Matteo
in case of short-circuit inside or downstream an electrical cabinet (supplied from a low voltage 50/60 Hz grid), the electrodynamic forces amongst the conductors inside the cabinets can be relatively high.
Here is an example of a paper that deals with this subject:
https://www.studiecd.dk/cahiers_techniq ... ystems.pdf
Is there a way to estimate with elmer:
1. the short-circuit currents (these could be computed with other means and given as an input to elmer)
2. the electrodynamic forces generated by the short-circuit currents
3. the deformation of the busbars during the event
4. the forces acting on the busbars supports (isolators, metal brackets...)
5. during the event, the temperature of the busbars can raise by let's say 100-200 K:
5a) can elmer estimate the power losses and temperature rises of the busbars during the short-circuit event?
5b) the temperature increase can change the mechanical properties of the busbars. Can this be taken in account by the solver?
While the currents can be assumed to be independent on what happens inside the cabinet, the electrodynamic forces depend on the distance between the conductors and thus on their deformations. So forces and defomations of the conductors are a coupled problem. (if deformations are small compared to the distances amongst the conductors, than the deformations can be neglected for the sake of calculation of the electrodynamic forces).
Point 5 of the previous list goes into another level and could be neglected. Alternatively, the busbar temperature rise could be estimated in other ways, knowing the current and the resistivity of the conductors.
Has anyone had any experience with elmer on this kind of problems?
Are there any example available?
Thanks,
Matteo