Diapositive 1

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• Power System Impacts from Large Scale Deployment
  of EV
• The MERGE project
• João A. Peças Lopes
• (jpl_at_fe.up.pt)

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• How to evaluate grid impacts from the presence
  of EV?
• Steps to be performed
• Need to understand the behavior of EV drivers ?
  Surveys
• Impacts in Power System operation and planning
• Steady state operation
• Dynamic behaviour
• Generation reserve needs
• Definition of management solutions with
  implications on battery charging modes
• Design of charging infrastructures

Specific simulation tools capable to incorporate
EV drivers behaviours and new management and
control concepts.
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EFFECT OF DUMB CHARGING SCENARIO ON PORTUGALS
ELECTRICITY DEMAND AND DISTRIBUTION SYSTEMS (10
EV)
CONTROLLED CHARGING IS REQUIRED
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Conceptual Framework for EV Integration Into
Electric Power Systems Possible EV charging
approaches and drivers behaviours

• Charging approaches

Dumb Charging - EV owners are free to charge
their vehicles whenever they want electricity
price is constant along the day. Multiple Prices
Tariff - EV owners are free to charge their
vehicles whenever they want electricity price is
not constant along the day. Smart Charging -
envisions an active management system, where
there are two hierarchical control structures,
one headed by an Aggregator and other by the DSO,
that control EV charging according to
Aggregators market negotiations or according to
the grids needs.
EV electricity cost

• Drivers behaviours

Behaviours defined according to the findings of a
survey made within the framework of the MERGE
project
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The MERGE control concept

• A two level hierarchical control approach needs
  to be adopted
• Local control housed at the EV grid interface,
  responding locally to grid frequency changes and
  voltage drops
• Upper control level designed to deal with
• short-term programmed charging to deal with
  branch congestion, voltage drops performed at
  the aggregation level and involving a dialog with
  the DSO
• Delivery of reserves (secondary frequency
  control)
• Adjustments in charging according to the
  availability of power resources (renewable
  sources).

Adoption of an AC charging mode 3, using the
control pilot connection
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Conceptual Framework For EV Integration

• EV must be an active element within the power
  system
• The Upper Level control requires interactions
  with
• An Aggregating entity to allow
• Controlled charging
• Reserve management
• Market negotiation
• DSO

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EV Voltage / Frequency support modes
Communication infrastructure
Active rectifiers or should be adopted to
interface EV with the grid.
Local control to be implemeted in a similar way
to SAE 1772
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Evaluation of EV Impacts in Distribution Networks
1 Case study typical Portuguese LV grid
(residential area)

• Data and assumptions
• Peak load 25.1 kW
• Annual energy consumption 111 MWh
• Vehicles in the network 30
• 30 of the fleet of vehicles are electric
• Period of lower energy price for Multiple Tariff
  Policy adherents 23h to 6h

• Results
• Power demand

Impossible approaches
Single line diagram of the LV test network
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Evaluation of EV Impacts in Distribution Networks
2 Case study typical Portuguese LV grid
(residential area)

• Voltage profiles for the peak hour

• Results
• Branches loading for the peak hour

• Weekly losses

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Evaluation of EV Impacts in Distribution
Networks Case study typical Portuguese MV grid
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Evaluation of EV Impacts in Distribution Networks
Case study typical Portuguese MV grid
Load increases after first and final day travels
Valley hour filling
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Evaluation of EV Impacts in Distribution Networks
Case study typical Portuguese MV grid
Dumb Charging
No EV
Smart Charging
Dual Tariff Policy
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Reserve Provision with EV Local Droop Control and
Automatic Generation Control (AGC)
Droop Control for EV
AGC Model with EV
Aggregators
PRIMARY FREQUENCY CONTROL
SECONDARY FREQUENCY CONTROL
Control loop for EVs active power set-point
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Reserve Provision with EV - Local Droop Control
and Automatic Generation Control (AGC)
Simplified Portuguese Transmission Network
Droop Control for EV
SECONDARY FREQUENCY CONTROL
PRIMARY FREQUENCY CONTROL
Control loop for EVs active power set-point
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Reserve Primary Reserve - Frequency Control with
EV
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Secondary Reserve - AGC Operation with EV
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CONCLUSIONS

• Electric Vehicles will play an important role in
  the development of the Smart Grid concepts since
  they are
• High flexible load device
• Mobile storage device
• The presence of Electric Vehicles, if properly
  managed, can
• provide several ancillary services
• allow a larger integration of renewable power
  sources
• increase system robustness of operation.
• If Smart Charging and other Distributed
  Intelligent solutions are adopted, the need to
  reinforce the existing electrical grid and
  generation infrastructures can be postponed.

http//www.ev-merge.eu/
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