The distance
between the power plant and the available AC
grid substation may tens kilometres.3 Protection
OPHELIA’S protection strategy multi-terminal
radial MVDC electric network with bidirectional
DC-AC converter must consider the high short-
circuit current the entire MVDC network in
case pole-to-pole faults [52]. Network reconfiguration facilitated by
disconnectors located all nodes.
6.1. DC-DC converters ensure the
maximum power point tracking strings, and
they limit the active power requested the utility
grid operator. estimated
that the capacity for such linear deployments
in France [51].4 Implementation
The OPHELIA project demonstrator has
been implemented with:
§ DC-AC converter station consisting a
unidirectional multilevel 800 kVA converter. The DC-AC
converter station protected with circuit
breaker; each MVDC feeder protected with a
DC circuit breaker, and each DC-DC converter
is protected with fuse. The target voltage for
future expansion ±10 higher.
6. The DC-AC converter
also controls the reactive power the connection
to the grid.1 OPHELIA architecture
The pilot phase the OPHELIA project consists
of 900-meter-long plant with capacity of
approximately MWp. The sections land question
retain their original use while electricity production
becomes complementary activity.
The protection scheme consists and
DC circuit breakers and fuses.5% efficiency. detect pole-to-
ground faults the MVDC network which uses
a high impedance earthing system the protection
system also requires insulation monitoring
device.1. The pilot project consists
of three DC-DC converter stations, which are
interconnected radial MVDC network
operating DC.1.1. Pilot project black, target
architecture for future expansion blue
MVAC HVAC
MVDC
LVDC
DCSST
. Future phases are planned
to include plants some long with power
outputs MW. The electrical architecture
is based around one DC-AC converter station
and several DC-DC converter stations, as
shown Figure 6-1.
6.1.1.), leaving natural spaces
as they are. This high short-
circuit current due the converter and cable
capacitive discharge and the grid short circuit
contribution.2 Control
OPHELIA’S MVDC network voltage controlled
by the DC-AC converter.50
MVDC projects around the world
roads, cycle paths, etc. central controller implemented
to manage start/stop sequencing and converter
setpoints.
6.1. Such plants may only
a few meters wide but could reach length of
many kilometres, and peak power over tens
of megawatts (roughly MWp/km).
Figure 6-1 Electrical architecture the
OPHELIA project.1.
§ DC-DC converter stations with 2-stage
250 solid state transformers with
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