Investigation of a micro DC power grid in Glava
Hillringsberg – a smart grid
The technical development has made
obsolete the previous motivation for use of alternating current
instead of direct current.
In local networks and building installations, direct current
nowadays has a number of advantages compared with using
alternating current. Almost all electrical appliances have
changed the electrical character to being electronic devices.
Almost all appliances have and will have electronic interfaces
to the electrical grid. Current breaking, which was previously a
large problem, is no longer crucial. The problem has disappeared
with electronic loads. See ref. video 1, Breaking DC current to
At the same time, the basic design of all new
appliances is clearly that of DC appliances.
In addition, in today’s design, they are multi-current and
multi-voltage appliances, which can run on both direct and
alternating current. In upcoming designs, as only DC appliances,
they can be more efficient than today’s appliances. This change
has been driven by the development of electronics and the desire
to achieve the highest possible efficiency in the use of
electricity. More recently, the desire for increased efficiency
in the use of new local energy sources, in particular solar
cells, has pushed ideas in the direction of the use of direct