Medium Voltage Direct Current Distribution System
for an Electric Vehicle Fast Charging Park
JESUS QUINTERO-ARREDONDO, HA THU LE
Department of Electrical and Computer Engineering,
California State Polytechnic University, Pomona,
Pomona City, California 91768,
UNITED STATES OF AMERICA
Abstract: – There is an increasing shift towards the electrification of automobiles to meet zero-emission
standards set by many nations. As electric vehicles become more common, their power demand on the power
system becomes greater. A substantial modernization or upgrade of the current distribution power grid is
required to meet such demand. Since most Level 3 fast chargers utilize DC power, medium voltage direct
current (MVDC) provides a feasible alternative to the present AC distribution infrastructure. This study
proposes an MVDC distribution model for powering a large EV park consisting of 40 EV charging stations
with a 9.6-MW total power demand. Calculation and simulation are used to evaluate the model and compare it
with an equivalent MVAC system. The outcomes show that implementing an MVDC distribution system is an
efficient approach to meeting the increasing power demand for electric vehicles. The proposed 40-kV MVDC
system power loss (13.1kW) is six times lower than that of the equivalent MVAC system (89.74kW). Further,
since MVDC systems do not require AC step-down transformers and AC/DC converters at the equipment end,
they can be a lower-cost option for powering large EV charging parks. The findings help enhance EV charging
infrastructure, which expedites the adoption of EVs for reducing carbon emissions in the transportation sector.
Key-Words: - AC-DC conversion, charging park, distribution power system, electric vehicle, Level 3 charging,
medium voltage direct current (MVDC).
Received: November 22, 2023. Revised: December 20, 2023. Accepted: December 29, 2023. Published: December 31, 2023.
1 Introduction
Electric vehicles (EVs) are currently being
promoted by many nations to reduce the reliance on
fossil fuels for passenger vehicle travel and also to
meet zero-emission standards and goals set by
various governing bodies. In the upcoming years, as
EV costs trend down and are more widely adopted
by the populace, a convenient charging method will
need to be provided. The Society of Automotive
Engineers (SAE) has provided the international
standard SAE1772 providing direction for three
levels of charging that are available to be installed at
residences and commercial locations. Forecasts
considering the various government and
environmental incentives for electric vehicles show
a sharp increase in EV adoption in mid-2020’s and
by the start of the 2030s, roughly 50% of vehicle
sales will be electric, as shown in Figure 1, [1].
The high rate of forecasted adoption of electric
vehicles in the upcoming decades requires research
and planning into new technologies to support the
additional power demands of EV charging.
On a commercial scale where charging speed and
consumer convenience are a priority, Level three
EV charging set by the SAE 1772 standard is a
suitable choice and will be used as the basis of our
load in a medium voltage direct current (MVDC)
microgrid that we aim to develop in this study.
Level 3 charging is characterized by containing a
DC voltage ranging from 200 to 600V, a maximum
current less than or equal to 400A, and a power
capability of up to 240kW, [2]. The differing
characteristics of Level 3 charging in comparison to
Level 1 and Level 2 charging, in the consumer
perspective, is charging speed.
Fig. 1: Electric vehicle adoption rate in the
upcoming decades, [1]
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The DC Level 3power output of up to 240kW
allows most current vehicles to charge from near
depleted charge to 100% within one hour, [3].
EV charging time is critical when comparing
refueling times for traditional internal combustion
engine (ICE) vehicles as consumers prefer similar
times when opting for EVs. With such a large power
requirement for a single charger, it becomes
apparent that having multiple EV chargers to
support multiple customers simultaneously fed from
a single power circuit will require a renewed look at
the present power system infrastructure to supply
the load, [4], [5].
Medium voltage DC distribution is a possible
alternative to supply the DC nature of EV charging
more efficiently and cost-effectively than the
traditional AC power system, [6]. Medium voltage
DC is of growing interest with the commercially
successful construction and implementation of
High-Voltage DC (HVDC) transmission lines
throughout the globe. Large amounts of research
have been done on the topic of HVDC concerning
constructability, materials, and power electronics.
MVDC theory is an extension of principles
developed with HVDC at a much lower voltage and
physical scale, [7], [8].
HVDC is a more efficient means of transmitting
power along large distances. The most critical
analysis when designing and selecting HVDC as a
means of transmission is the equipment cost versus
transmission line distance. This is due to the
complexities involved in rectification and inverting
the generated AC power, [9].
Based on the increasing interest in MVDC as a
method to efficiently distribute power, the adoption
of electric vehicles utilizing DC electricity as a
method of charging, and large power requirements,
this study will consider a hypothetical model of an
EV Charging Park where consumers can
conveniently charge in a short time and analyze the
feasibility of an MVDC power system, its
constructability, and efficiency over the existing AC
power system. A DC distribution grid is more
favorable over AC power systems when considering
the continued implementation of DC technologies,
[10], [11], [12].
MVDC can coincide with the existing MVAC
distribution infrastructure providing additional
services where required, [11]. Figure 2 shows
possible implementations of MVDC in conjunction
with the existing power system MVAC power grid.
A search of the literature did not find any study
where an MVDC network is used for an EV
charging park. This motivated us to design an
MVDC EV charging park. The expected benefit of
our study is improving understanding of MVDC
network capability for EV charging, as well as
determining the park core features and
specifications. The findings will enable the
implementation of MVDC networks for expanding
EV charging infrastructure, which expedites the
adoption of EVs for reducing carbon emissions in
the transportation sector.
2 Basis of Design for EV Charging
Park Utilizing MVDC
2.1 EV Charging Park Concept.
For our study, the EV charging park will serve a
similar function as a traditional gas station. It will
allow consumers to arrive and conveniently charge
their EVs in a reasonable time. Due to the inherent
relative charging times required for EVs it will have
to be placed in a location where the consumer can
be occupied for a minimum of thirty minutes such
as a recreational park, commercial plaza, urban
environments close to social amenities, etc. to allow
for a sufficient charge. It will also require a
substantial quantity of charging stations to prevent
waiting times for incoming vehicles.
2.2 Charging Park Sizing
The hypothetical charging park can also function as
a recreational park where consumers go to picnic,
take their children to playgrounds, access public
basketball courts, and tennis courts, have social
gatherings, etc. A location such as this is ideal for an
EV user to charge their vehicle and have local
amenities while the vehicle charges. Local Los
Angeles County ordinances provide minimum
parking space requirements based on acreage for
private and public parks. One space per half-acre of
developed park for parks up to fifty acres.
Community parks are described as areas
designed to serve residents of several surrounding
neighborhoods with an ideal size of fifteen to twenty
acres and a service radius of a minimum two miles.
At a given park size of twenty acres, a proposed
minimum of 40 charging stalls shall be proposed in
the community park meeting parking space
minimums and used in our model. Additional
standard non-EV parking can be provided to
accommodate regular ICE vehicles. The 40 EV
stalls can be split between separate parking areas
within the park to reduce congestion, [13], [14]. It is
important to consider local and state ordinances as
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well as actual land size when planning for the
quantity of EV charging parks.
2.3 EV Charging Standards
Level 3 DC charging will be utilized for our EV
charging stations. Table 1 shows the standard set by
SAE for each level of charging and requirements
needed to be fulfilled by our MVDC power system,
[2].
Our model and analysis only consider DC
charging as part of our MVDC power system. This
is to remove the necessary AC/DC conversion at the
station end. Level 3 charging for each charging
station can utilize a maximum power of 240 kW,
[2].
With a total of 40 stations, it follows that our
model utilizes a maximum of 9.6 MW of power.
Our MVDC feeder circuit is required to sustain that
quantity of power as part of the design and analysis.
It should be noted that there are multiple EV
charging standards, such as the Society of
Automotive Engineers (SAE) J1772, Japanese
industry “Charge-de-Move” (CHAdeMO), CharIN
organization combined charging system (CCS),
Chinese and Indian EV manufacturers Guobiao
standards (GB/T), and Tesla supercharger network,
[15]. For our study, we utilize Level 3 DC charging
specification which is part of SAE standard J1772.
Other charging standards are not used so they are
not discussed here for brevity.
2.4 MVDC System Specification
Medium voltage DC distribution power system is a
topic of research that has not been widely
implemented at a utility level. At the time this
research was conducted, there were no standardized
voltage levels and industrial practices widely
adopted for MVDC as shown in [6]. Our
implementation of an MVDC grid for our model
utilizes previous research papers and reference
HVDC implementations that can be appropriately
applied to MVDC.
a) Line and cable design
There are different cable designs for MVDC
currently proposed based on the station design and
distribution method. The line design chosen for our
system consists of two fully insulated conductors.
Other line designs proposed are a single-
conductor with full insulation and 3-conductors with
two fully insulated and one less insulated conductor,
[16]. The 2-conductor line design is chosen as a
compromise between power safety and cost.
Our two-conductor line design shall also be
capable of supporting our maximum power load for
the EV charging park and able to accommodate
future growth within the system. Various cable sizes
will be compared to analyze the appropriate cable
sizes to utilize for a 9.6 MW electrical load.
Table 1. Charging mode characteristics, [2]
Type
Level
Input
Max
Power
Output
(kW)
AC (On-
Board
Chargers)
Level
1
120 VAC
(1-phase)
≤ 1.92
kW
Level
2
208-240
VAC
(1-phase)
≤ 19.2
kW
Level
3
208-240
VAC
(1 and 3-
phase)
≤ 96
kW
DC (Off-
Board
Chargers)
Level
1
200-450
VDC
≤ 36
kW
Level
2
200-450
VDC
≤ 90
kW
Level
3
200-600
VDC
≤ 240
kW
Fig. 2: Possible MVDC grid infrastructure
Consideration of conductor material is also
required. The most widely used materials for cable
design are copper or aluminum conductors. Both
have their respective benefits and trade-offs. Copper
conductors can support higher amperage than
aluminum conductors at the same wire gauge, [17],
while also having substantially less impedance.
Aluminum conductors are less expensive than
copper conductors and lighter than their respective
counterparts allowing for ease of installation, [11].
The trade-off between performance and cost is one
for engineers to consider when designing the cable
plant for MVDC.
Our study primarily focuses on enhancing the
efficiency of the power system. As such, copper
cable conductors are selected for their reduced
impedance providing for higher power efficiency
transfer and reduced overall diameter at the chosen
ampacity, [18], [19].
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Selecting copper conductors for the cable plant
considers higher initial capital expenditure while
also providing a lifetime of the conductor power
efficiency gains when compared to aluminum
conductors. The proposed DC park considers a 1-
mile distribution length from the substation. This
length is relatively short when considering existing
utility distribution systems where one distribution
feeder can provide service for dozens of miles. As
distance increases efficiency savings become more
crucial, and copper conductors are recommended.
b) DC power station design selection
Three different versions of DC station designs have
been researched for MVDC and implemented at the
HVDC scale, [7]. The three versions (Figure 3) are:
Asymmetric monopolar
Symmetric monopolar
Bipolar
Each station design is correlated to the line
design selected. As part of our 2-conductors with
full insulation design, our chosen station design is of
a symmetric monopolar design. As shown in Figure
2, the neutral point for a symmetric monopolar is
placed symmetrically between both lines. Therefore,
the rated voltage of the system will be halved with
respect to neutral. The voltage between the lines
will be considered the nominal MVDC voltage.
Furthermore, the symmetrical monopolar design
with the use of modern DC-DC converters, such as
dual active bridge in [20], allows future
considerations to be given to implement vehicle-to-
grid bidirectional power flow operation, [20], and
leveraged to assist in maintaining a more stable
power system, [21], [22].
c) Distribution planning and operation design
The operation of our proposed MVDC power
system does not differ from the commonly
constructed traditional AC power system. AC power
systems are commonly planned as a mesh system
but operated radially at the distribution level. The
different planning and operation design are shown
in Figure 4. This allows for a less complex
implementation at the utility-scale, [16]. Each feeder
circuit serves a specific area where carefully placed
interconnection points allow for redundancy when
maintenance is required, or emergency rerouting of
power is required in outages. Additionally,
maintaining a similar planning and operation design
allows power utilities to approach MVDC easily.
For the hypothetical model being proposed in
this paper, only a single circuit will be analyzed.
Further research will be required when considering
mesh connections and planning interconnections
between various MVDC feeder circuits.
d) Voltage level
Since MVDC is still in its infancy with respect to
deployment within the power system by power
utilities, no official or commonplace DC voltage
levels have been standardized, [6]. IEEE 1709
standard guides MVDC with respect to DC power
systems on ships, [23]. We use this as a guideline
when selecting a voltage level for our system.
Various parameters must be considered when
selecting a voltage level. First and foremost, the
voltage level has to be sufficient to support our
required power load of 9.6MW. Further, voltage
loss has to be within a specific range, maintenance
ease for workers has to be considered, power safety,
and power electronic equipment capabilities have to
be able to support the voltage level.
Commonly used feeder conductors for
traditional AC distribution power systems range
between 500-750 kcmil. Table 2 displays the
maximum power capacity for various distribution
levels for a 500kcmil conductor at 400 amperes,
[23], [24]. The 500 kcmil copper conductor
ampacity, as specified by Southwire manufacturer,
is 455A, [19], allowing for future overhead or
further power capacity. Resistive line loss and
AC/DC conversion efficiency loss will be
considered when analyzing a theoretical
performance for MVDC distribution.
Fig. 3: Station and line concepts of DC grids, [16]
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Fig. 4: Power line configurations, [16]
Table 2. Medium voltage level feeder capacity,
[23], [24].
Type
Voltage
Level
Nominal
MVDC
Class
Distribution
Type
Max
Power
(MW)
AC
4.8 kV
-
3-phase
Delta
3.32
MW
13.8 kV
-
3-phase
Delta
9.56
MW
22.9 kV
-
3-phase
Delta
15.86
MW
34.5 kV
-
3-phase
Delta
23.90
MW
DC
±3 kV
6kV
Symmetric
Monopolar
2.4 MW
±6 kV
12kV
Symmetric
Monopolar
4.8 MW
±12 kV
24kV
Symmetric
Monopolar
9.6 MW
±15 kV
30kV
Symmetric
Monopolar
12 MW
±20 kV
40 kV
Symmetric
Monopolar
16 MW
Table 3. EV charging park electrical specification
Parameter
Value
EV Charging Park
Charging Level
Level 3
Charging Level Output
240 kW
Charging Station Quantity
40
Max Park Power Load
9.6 MW
MVDC
Line Design
Two-Conductor Insulated
Station Design
Symmetric Monopolar
Planning/Operation
Design
Mesh Planned / Radial
Operated
Voltage Level
±20 kV
Conductor Sizing
500 kcmil
Conductor Max Ampacity
465 Amps
Max Feeder Capacity
≈16 MW
Table 4. Electrical cable specifications and
electrical data, [19]
Characteristic
Value
Conductor Size
500 Kcmil
Approx O.D.
1.819 inch
Approx Weight
3.64 lb/ft
DC Resistance @ 25°C
0.0216 Ω/1000ft
AC Resistance @ 90°C
0.028 Ω/1000ft
Capacitive Reactance
@60Hz
0.027 MΩ/1000ft
Inductive Reactance @60Hz
0.040 Ω/1000ft
Allowable Ampacity @
90°C
455
Dielectric Loss
153.971 W/1000ft
2.5 EV Charging Park Parameters
As shown in Table 2, the most commonly used
voltage levels of distribution cannot accommodate
the required power load for our proposed EV
charging park. The minimum nominal voltage class
capable of supporting the power demand is 24kV
nominal DC. At 24-kV DC there is no additional
headroom for expansion. At 40kV MVDC, the
selected voltage can support our load and
accommodate future growth for the system.
Therefore, our charging park specification is chosen
as shown in Table 3. Electrical cable specifications
and electrical data are provided in Table 4.
3 EV Charging Park Performance
and Efficiency Analysis
Our model considers a maximum load scenario for
the charging park, as well as a one-mile cable feed
from its respective substation. At the substation, the
generated power will be converted to the chosen
±20 kV MVDC (Nominal 40kV).
Utilizing and selecting a 25kV rated copper EPR
cable from Southwire, we acquire electrical data
from the cable. Its electrical specifications are
shown in Table 4.
Equation (1) is the standard Ohm’s law equation.
Utilizing Ohm’s law allows us to calculate the
voltage loss in the MVDC line at the one-mile
distance. DC resistance is utilized, and any
reactance is ignored.
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The amperage through the circuit at the given
power load is calculated using equations (2), (3),
and (4). We can calculate the given voltage loss at
27.37 volts after a one-mile length. The complete
round-trip path for the MVDC circuit is two miles.
Given this, the actual voltage loss to provide power
to the EV chargers is twice the voltage loss of our
calculated one-mile calculation at 54.74 volts.
Voltage loss as distance increases is linear as shown
in Figure 5. The total percentage drop for voltage is
0.272% and within the margins of a stable power
system at typically less than 5%.
The resistive power loss for providing power to
40 EV charging stations at a 1-mile distance is
6.55kW. The round-trip power loss is 13.1kW and
the efficiency of power transfer is 99.86%.
Further power loss calculations using equation
(3) are completed as shown in Figure 5. The figure
displays the linear relationship between the resistive
power loss as cable length is increased. This
analysis is useful in the planning of MVDC circuit
origination.
Fig. 5: Power loss is linear as the cable distance to
the EV charging station is extended
Fig. 6: Exponential power loss as the cable is loaded
to its maximum allowed ampacity
Table 5. Efficiency of energy conversion equipment,
[17].
Voltage
rating (kV)
Energy conversions equipment
efficiency (%)
±320
98.4
±150
98
±30
97.6
±10
97.2
Given the minimal power loss shown by the
MVDC circuit, EV chargers can be provided at
greater distances than one mile and up to 18 miles
before a 5% voltage loss is reached.
Additional calculations are completed with
equation (5) to gain further insight into power loss
as cable power loading increases. Figure 6 displays
the power loss for the 1-mile cable scenario. As
power loading increases to its maximum allowed
ampacity of 465 amperes, a substantial exponential
power loss increase occurs in contrast to findings in
Figure 5 where power loss is linear in nature.
As shown in Figure 6, a doubling in the current
quadruples the cable power loss in our test scenario.
Both Figure 5 and Figure 6 provide important
information when planning MVDC distribution
cable plants to support EV charging. It is important
to consider the power loss caused by additional
power load and cable distance and its implications
for future load growth against the cost of installing a
secondary MVDC cable to service additional loads.
Additional power losses shall be considered such
as the dielectric loss, AC/DC conversion at the
substation, and DC/DC conversion as shown in
Table 5, [17]. Research on DC conversion has been
conducted, [16] and shown in Table 5. It is
important to consider advances in DC conversion at
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Cable Power Loss (kW)
Cable Power Loss (kW)
the utility-scale and improved efficiency to be
gained for MVDC. Table 5 displays high efficiency
in the upper 90% range for DC conversion using
newer technologies, [17].
4 Comparison of MVDC and MVAC
Power Distribution Systems
In this section, we compare our proposed MVDC
design with a traditional MVAC system using
MATLAB Simulink. Figure 7 shows a visual
representation of both a traditional MVAC and
required transformer and AC/DC converters at the
local equipment level. The MVDC scenario would
provide AC/DC conversion at the substation level
and distribute at MVDC to equipment.
Our 40-kV MVDC model and the power line
loss and efficiency will be compared to a 22.9kV
MVAC power system like the study in [25].
4.1 MVDC Simulation and Analysis
Simulation setting
MATLAB Simulink is utilized to validate the design
specification and parameters for our MVDC
distribution, as shown in Figure 8.
The first section of our simulation for validating
our design is to create a Thevenin power source
matching our parameters of nominal 40kV DC
(±20kV) in a symmetrical monopolar design. The
voltage and current provided by the source are
shown in Figure 9.
The second section is our DC distribution line as
chosen from our design specification and cable
parameters. Electrical specifications of our
500kcmil underground copper conductor are
incorporated into the simulation.
The third section is our equivalent power load
from our DC charging park. A total of 40 Level 3
charging stations has an equivalent load of 9.6MW
and are modeled as a resistive load in the
simulation.
MVDC power loss quantification: Power at the
source and the DC EV park is calculated in the
simulation by utilizing Equation (2) at each end.
The power loss is then calculated by taking the
difference between them (i.e., the difference
between input and output), as shown in our
simulation in Figure 8.
Results
Figure 9 shows the voltage source displaying ±20kV
and 240 amperes for current. These are expected
values proving that our MVDC network for
simulation works accurately.
The simulated power loss of 13.1kW of the
MVDC distribution matches power loss calculations
completed in Section 3 of the paper and verified by
values shown in Figure 10.
4.2 MVAC Simulation and Analysis
Simulation setting
An equivalent MVAC system in Figure 11 is
simulated to provide a power efficiency comparison
to our MVDC model. A 22.9kV 3-phase delta
system is selected as our equivalent MVAC system.
From Table 2, the selected MVAC cable feeder
power capacity is 15.86MW. This is comparable to
our Nominal 40kV MVDC system at 16MW.
Fig. 7 (a): Existing fast charging infrastructure
utilizing AC distribution grid. (b) proposed
infrastructure utilizing MVDC to EV chargers, [11].
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Fig. 8: MVDC Simulink simulation is composed of 3 separate sections: MVDC source,
bipolar distribution line, and equivalent DC EV Park load
Fig. 9: Voltage source displays ±20kV and expected 240 amperes for current
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Fig. 10: The first and second plots display power before and after the modeled distribution line, respectively.
Third row graph is our line power loss
Fig. 11: The MVAC Simulink simulation consists of three sections similar to the MVDC simulation along with
various scopes for analysis. The three sections are a MVAC Thevenin power source,
3-phase distribution power line, and an equivalent EV DC Park power load
Fig. 12: 22.9kV MVAC voltage source Simulink components
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Fig. 13: 22.9kV source current. Plot displays individual balanced phase currents and respective RMS value
Fig. 14: 22.9kV source voltage. Plot displays individual balanced phase voltages and respective RMS value.
Phase-phase voltage close to 22.9kV shows that our model is functioning normally
Fig. 15: Three-phase delta power line, interface to DC power load and power load in Simulink
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Fig. 16: Measurements blocks required to calculate power loss. Three-phase voltage and current measurement,
instantaneous power, RMS, difference blocks are shown at both power line ends
Fig. 17: MVAC power line loss
The Thevenin power source shown in Figure 12
is a combination of a three-phase 22.9kV voltage
source in series with a transformer to convert the
Wye voltage source to Delta configuration, which
matches our Delta distribution power line.
Interfacing a 9.6-MW DC load as an equivalent
to 40 Level 3 EV chargers requires additional
simulation components when compared to our
MVDC simulation. Voltage step-down
transformation from medium voltage to low voltage
is required. This is accomplished by transforming
the voltage down to 3-phase wye 480VAC. The
transformation is a real-world example as done by
existing utilities and required by current Level-3 EV
chargers. A simple rectifier is utilized for the
AC/DC conversion and is included between the 3-
phase low-voltage source and the equivalent power
load by our charging park, as shown in Figure 15.
MVAC power loss quantification: The 3-phase
22.9-kV distribution power line parameters are
based on the same selected 500kcmil underground
copper conductors from our specifications in
Section 3. Power values from our simulation are
received from specific three-phase instantaneous
power measurement blocks available in Simulink
(as shown in Figure 16) before and after the power
line. To capture the power line loss value, we take a
difference in the RMS power value.
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Results
Figure 13 displays source phase currents and
respective RMS value. Figure 14 displays source
phase voltages and respective RMS value where line
voltage is close to 22.9kV. Both figures show that
our MVAC model is functioning normally.
Figure 17 shows a power loss of 89.74kW for the
MVAC distribution power line, more than 6 times
the power loss of the proposed MVDC distribution
system. The increased resistance from skin effect,
capacitive and inductive reactance, and lower
voltage when compared to our MVDC model are
shown to cause a substantial power loss.
Key findings from MVDC and MVAC comparison
Both MVDC and MVAC function appropriately
where there is no abnormality in terms of voltage
and current.
The MVDC distribution system is superior as
compared with the MVAC system in terms of power
loss. Its loss is only 13.1kW, which is 6 times lower
than that of the equivalent MVAC system
(89.74kW).
5 Conclusion
In this study, we proposed an MVDC distribution
system model for powering an EV park consisting
of 40 EV charging stations. Calculation and
simulation are used to evaluate the model and
compare it with an equivalent MVAC system. The
study outcomes are summarized as follows:
a) Implementing an MVDC distribution system is
an efficient and cost-saving approach to meet
the increasing power demand by electric
vehicles. Our proposed 40-kV MVDC system
power loss (13.1kW) is six times lower than that
of the equivalent MVAC system (89.74kW).
b) MVDC systems have further advantages as they
simplify the construction of EV charging parks
by not requiring AC step-down transformers
and AC/DC converters at the equipment end.
This potentially lowers the cost for power
utilities supplying such EV charging parks.
In terms of future study, additional analysis is
required for power efficiency, cost, and power
system protection where MVDC is considered. Cost
and efficiency of AC/DC converters at the
substation level should be considered when cost-
benefit analysis is conducted to implement MVDC
or upgrade of existing MVAC infrastructure.
Increasing research is currently being done in
AC/DC conversion for MVDC as well as
transferring applicable breakthroughs in HVDC
which have applicability at the lower voltage levels.
Overall, the benefits of our study include some
insightful understanding of MVDC network
capability for EV charging and power distribution in
general, and key MVDC network features and
specifications. These findings help enable the
implementation of MVDC networks for expanding
EV charging infrastructure, which expedites the
adoption of EVs for reducing carbon emissions in
the transportation sector.
Acknowledgment:
The authors would like to thank the Master project
committee members, Dr. Dennis Fitzgerald and
Dr. Tim Lin, for your time and feedback. The author
Jesus Quintero-Arredondo would like to thank his
project advisor, Dr. Ha Thu Le, who has helped him
throughout the development and finalizing of the
thesis report.
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WSEAS TRANSACTIONS on POWER SYSTEMS
DOI: 10.37394/232016.2023.18.41
Jesus Quintero-Arredondo, Ha Thu Le
E-ISSN: 2224-350X
423
Volume 18, 2023
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WSEAS TRANSACTIONS on POWER SYSTEMS
DOI: 10.37394/232016.2023.18.41
Jesus Quintero-Arredondo, Ha Thu Le
E-ISSN: 2224-350X
424
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Contribution of Individual Authors to the
Creation of a Scientific Article (Ghostwriting
Policy)
- Jesus Quintero-Arredondo: Identification of
research issues, system data acquisition, design
and implementation, simulation, writing an
original draft, and revising.
- Ha Thu Le: Refining research issues and scope,
methodology, technical advising, refining
simulation scenarios, review of results, formatting
and editing the final draft, revising the reviewed
paper to meet review requirements.
Sources of Funding for Research Presented in a
Scientific Article or Scientific Article Itself
No funding was received for conducting this study.
Conflict of Interest
The authors declare that they have no known
competing financial interests or personal
relationships that could have appeared to influence
the work reported in this paper.
Creative Commons Attribution License 4.0
(Attribution 4.0 International, CC BY 4.0)
This article is published under the terms of the
Creative Commons Attribution License 4.0
https://creativecommons.org/licenses/by/4.0/deed.en
_US
WSEAS TRANSACTIONS on POWER SYSTEMS
DOI: 10.37394/232016.2023.18.41
Jesus Quintero-Arredondo, Ha Thu Le
E-ISSN: 2224-350X
425
Volume 18, 2023