45
Amid the benefits and opportunities MVDC
technology outlined the previous section, MVDC
power grids remain novelty, limited relatively
small number installations around the world. Metals with
higher reactivity are more prone oxidize (or
corrode).
The issues that contribute the risk corrosion
in MVDC power system include:
§ Improper grounding design grounding
system failures: They can lead induced
currents metal surfaces within the
MVDC power system.
5.1 Technical challenges
5. Due the
unidirectional and continuous nature current flow
in systems the risk electrochemical corrosion
is much higher than their counterparts.
Corrosion can cause structural damage, electrical
system failures (through degradation electrical
connectors), safety hazards and increased
maintenance costs.
Various methods are available prevent reduce
the risk corrosion:
§ Selection corrosion-resistant metals such
as stainless steel aluminium alloys. Induced currents
create potential differences between metal
structures, and the presence electrolytes
(e.
For MVDC power grids grow meaningfully in
number and become widely accepted, several
challenges and issues will need addressed.
§ Inadequate insulation: electrical connections
or equipment within power systems are not
adequately insulated, direct contact between
dissimilar metals can cause galvanic corrosion.
§ Mitigation galvanic corrosion through the
choice compatible metal combinations,
Section 5
Barriers the uptake MVDC grids
. particular, marine high-
humidity environments pose elevated risk
of corrosion.
§ Environmental conditions: Humidity, salinity,
temperature fluctuations, exposure chemical
substances and other environmental factors
act major accelerants corrosion DC
power systems.
§ Galvanic corrosion: Two different metals in
contact with each other are exposed an
electrolyte (such moisture), leading to
accelerated corrosion the more reactive
metal. As
an example, leakage current flows from
iron metal earth for one year, around the
original metal would lost rust [47].1 Electrochemical corrosion
Corrosion refers the degradation metals
through electrochemical reactions with their
environment, leading weakened structural
durability, long-term functional loss, and
compromised safety and reliability. moisture substances containing salt),
they significantly accelerate electrochemical
corrosion.
§ Corrosion from polarization: current
passing through metal accelerates the rate
of corrosion.1.
This accelerates the rate metal degradation.
These are looked the following sections. Corrosion caused by:
§ Metal reactivity: Metals naturally oxidize due
to their own reactivity and interaction with
the surrounding environment.g