direct current (dc) smart grids in production
TRANSCRIPT
Direct Current (DC) Smart Grids in Production
M. Sc. Raoul Laribi
04 June 2019
Stuttgart, Germany
Facilitator
Conclusion7
Economic benefit6
Application tests5
Decentralized intelligent control4
Research project DC-INDUSTRIE3
Efficiency potentials of DC power supply2
Challenges of a changing power system1
Agenda
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AGENDA
The Energy Trans ition “Energiewende”
What are the challenges of the changing power system?
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CO2-Emissions
*17 %deviation
*19 %deviation
Primary Energy Consumption
CO2
Emissions
Climate protection goalsWhere do we stand today?
*forecast assuming continuation of current trend **on gross electricity consumption Source: based on Gesamtausgabe der Energiedaten – Datensammlung des BMWi (2017)
Germ
an
yW
orl
d
Primary Energy Consumption Share of Renewables**
- 50 % by 2050
80 % by 2050
- 80 % by 2050
2016
20202025
CO
2-E
mis
sio
ns
Time
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The factory in the context of a changing energy system
Hot Water Storage
Fossil Fuel(Oil, Gas etc.)
Electricity
Heating
HVAC
Heat Pump
MachineTool
MachineTool
CompressedAir System
CoolingPhotovoltaic System
CompressedAir
CHP
Shading
Ground Probes
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Challenges of a changing power systemA growing share of renewable power in Germany raises the need for a controllable energy demand.
Energy production of renewable power plants is volatile
For stable and secure energy supply energy production and consumption need to be balanced
The future energy market needs more active participation of industrial stakeholders within the supply grid
There is a need for controllable energy consumption and storage capacities
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Effiziency potentials of DC power supplyThe downside of the energy transition: outages
Quellen: Stuttgarter Zeitung, VDI, Heise, Handelsblatt
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Effiziency potentials of DC power supplyProtection against external disturbances andpower outages .
"Power outages of less than three minutes have increased significantly, and power utilities
now have to intervene more frequently to stabilize the grid. However, because they are
apparently increasingly unable to do so, companies with sensitive production processes are
working on strategies to get their energy supply up and running on their own.”
Gleichstrom statt Wechselstrom – Die wahre Revolution in der Fabrik ist nicht Industrie 4.0, wiwo.de
https://www.wiwo.de/unternehmen/mittelstand/hannovermesse/gleichstrom-statt-wechselstrom-die-wahre-revolution-in-der-fabrik-ist-nicht-
industrie-4-0/21184100.html
Fault
Short-term power outageswith a duration between
10 ms and 2 s
U < 10% ⋅ 𝑈𝑅𝑎𝑡𝑒𝑑
Voltage boost and reduction10 ms to 2 s
U < 90% ⋅ 𝑈𝑅𝑎𝑡𝑒𝑑U > 110% ⋅ 𝑈𝑅𝑎𝑡𝑒𝑑
Harmonicswith integer
multiples of the
fundamental
vibration
FlickerFluctuating voltage
shift
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Goal: Transfer the advantages of DC technology into industrialelectrical power supply
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Efficiency potentials of DC power supplyState of the art: DC-link systems
AC
DC
DC
AC
𝑓 = 50 𝐻𝑧 𝑓 = 𝑓2
Frequency inverter in the
robot axes with DC-link
circuit
Energy exchange
during braking and
acceleration processes
Coupling of
several axes
Facilitator
Efficiency potentials of DC power supplyA DC-grid offers reduced energy loss and system costs and a high availability*.
* H. Borcherding und T. Kuhlmann, „Energieeffiziente Gleichspannungsversorgung zur Versorgung von industriellen Produktionsanlagen,“ ZVEI, 2015.
Facilitator
Controlling complex systemsSystem concept of the research project DC-INDUSTRIE
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Research project DC-INDUSTRIELowering transmiss ion losses and increasingenergy flexibility.
"The aim of the project is to implement the energy transition in industrial production
and to bring more energy efficiency and energy flexibility into industrial
production. For this purpose, the power supply of industrial plants using a smart, open
direct current grid is to be redesigned and the industrial energy supply architecture is
to be digitized."
Forschungsprojekt 'DC-Industrie' startet, computer-automation.dehttps://www.computer-automation.de/feldebene/stromversorgungen/artikel/133233/
Facilitator
Assoz. Partner: ABB STOTZ-KONTAKT, E-T-A Elektrotechnische Apparate, HARTING, HOMAG Group, Jean Müller GmbH Elektrotechnische Fabrik , U.I. Lapp, LEONI Special Cables, Phoenix Contact, SEW-Eurodrive, Yaskawa, ZVEI.
Research project DC-INDUSTRIEWho we are.
Facilitator
Research project DC-INDUSTRIEDecoupling AC-grid and industrial power supply.
https://dc-industrie.zvei.org/
Facilitator
Research project DC-INDUSTRIESeparating the DC-grid into load zones .
Load zones…
form a logical unit
contain components that have strong functional interdependencies with each other
contain sufficient intermediate circuit capacity to keep switching frequency compensation processes between their devices away from the DC grid
are connected to the DC network via a DC junction =
3~
=
3~
=
3~
M M M
=
3~
M M M
=3~
=3~
=
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Speicher
=
=
Energie-
erzeugung
3~ Netz
Netz-
managment
· Regelung
· Planung
· Simulation
Kommunikations-
netzwerkM
=3~
3~
=
DC-Netz
LZ1 LZ2 LZ3 LZ4
LZ5LZ6
3~
=
A
V
V
A
V
V
A
V
VA
V
VA
V
VA
V
V
Facilitator
540 V: Suitable for uncontrolled feed-in on 400 V AC-grid
650 V: Suitable for controlled feed-in and unregulated on 480 V network
Rated operation
Unrestricted functionality of the devices.
Stationary overvoltage / undervoltage
Devices may be operated permanently in this area.
The functionality may be restricted (e.g. power reduction).
Active participants counteract the voltage deviation.
Transient overvoltage / undervoltage
Devices may lose their function, but must take over the function againafter returning to the stationary overvoltage/undervoltage range withouttaking any measures.
Voltage may only remain within this range for a limited time.
Switch-off limits: 400 V/ 800 V
Devices switch off permanently.
Research project DC-INDUSTRIEVoltage bands
010
020
030
040
050
060
070
080
090
0
400V
AC
480V
AC
&u
nge
erd
eter
Ste
rnp
unkt
DC
-Sp
ann
un
g in
Vo
lt
Eige
nsch
utz
Un
ters
pan
nu
ng
Tran
sien
te U
nte
rsp
ann
un
g
Stat
ion
äre
Unt
ersp
ann
ung
Nen
nb
etri
eb
Stat
ion
äre
Übe
rspa
nn
ung
Tran
sien
te Ü
ber
span
nu
ng
Eige
nsch
utz
Üb
ersp
ann
un
g
400V
540V
800V
650V
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Research project DC-INDUSTRIEFurther focal points of the research partners .
Electromagnetic Compatibility (EMC)
Short-circuit selectivity
Start-up and shutdown
Plug & Play capability
Planning and design tools
Are there any interfering signals?
When does which fuse trigger?
How can the DC network be safely
switched on and off?
Which interfaces are needed for an
extension of the network participants?
How large do generating plants have to
be?
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DC Smart Grid – Decentralized intelligent controlA digital solution for future energy distribution?
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System requirements of a Smart GridSmart Grid allows embedding devices in the energy control system by making information available.
Basic requirements
Reliability
Resilience
Stability
Low infrastructure costs
Todays requirements
Increasing efficiency
Enabling energy flexibility
Adapting to external effects
Future requirements
Open interfaces
Information availability
Versatile infrastructure
Facilitator
System requirements of a Smart GridSmart Grid allows embedding devices in the energy control system by making information available.
“A smart grid is an electricity network that uses digital and other advanced technologies to monitor and manage the transport of electricity from all generation sources to meet the varying electricity demands of end-users.
Smart grids co-ordinate the needs and capabilities of all generators, grid operators, end-users and electricity market
stakeholders to operate all parts of the system as efficiently as possible,
minimizing costs and environmental impacts while maximizing system reliability, resilience and stability.” IEA (2011)
Linking information and energy distribution
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DC Smart Grid – Decentralized intelligent controlHierarchical control
• Energy management
• Economic optimization
Tertiary
control
• Voltage restoration
• Improvement of supply quality
• State of charge control
Secondary
control
• Power flow
• Voltage und current control
• Droop control
Primary
control
Control
bandwidth
Time
scale
Source: Gao et al. 2019
incr
ease
s
h
min
s
ms
Facilitator
Fraunhofer IPA approach to industrial Smart GridsDecentralized control system for stable energy distribution.
Operation Principle
Modulation of energy availability as information on droop value (DC voltage)
Power control distributed in single devices (DC-DC converter, Active Front End)
Optional integration of any grid devicesInformation exchange
Energy distribution
Droop controlled
DC voltage
current
Facilitator
Fraunhofer IPA approach to industrial Smart GridsDecentralized control system for stable energy distribution.
Information exchange
Energy distribution
Advantages
No additional infrastructure for data transfer
Increased reliability by distributed control system
Modular expandability
Optional integration of energy flexible loads
Enabling optimized operation strategies
Simple customization of control systems for state of
the art power electronic devices
Droop controlled
Facilitator
DC Smart Grid – Decentralized intelligent controlInformation flow
Information exchange
Electrical energy distribution
Droop controlled
SPS Optional fieldbus communication
Functionality of droop control can be extended using fieldbus communication
Integration into energy market
Adaptation of new parametrization due to different load situation
Adaptation of new parametrization due to different supply situation
Facilitator
DC Smart Grid – Decentralized intelligent controlExample: PV module, energy storage and feed-in
current
DC voltage
Feed-in
Giv
ing
ener
gyto
the
DC
-gri
dTa
kin
gen
ergy
fro
mth
eD
C-g
rid
PV module
Energy storage
𝑈𝑅𝑎𝑡𝑒𝑑
current
DC voltage
Superposition
𝑈𝑅𝑎𝑡𝑒𝑑
Superposition of single droop curves leads to global system behavior
Slope of the droop curve depends on the device’s impedance (complex resistance)
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Application tests
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Application tests – DC Smart Grid in productionDeveloped device technology and network management are implemented in real spatially concentrated and distributed networks .
Production cell from body-in-white construction (Daimler)
Further development of the test facility from the ongoing EU project AREUS to investigate the following aspects:
Energy distribution
EMC
Harmonization
Electric monorail conveyor (Daimler)
3 individual drives per conveyer supplied via slip rings
Conversion of slip ring supply to DC
Feasibility of coupling production cell to be investigated
Facilitator
Gains by DC-Smart-Grid
Increased autarky in case of power failure
Lower AC-connection charges by reduced installed power
Higher process stability leads to increased quality
Decreased purchase costs for external energy
Application tests – DC Smart Grid in productionScenario 1 – Production cell of chass is construction containing robotics and welding process .
Facilitator
Application tests – DC-Smart Grid in productionScenario 3 – Wood process ing machine
Modularly constructed machine contains
Control technology
Protection and switching technology
Traction inverters
Sensors & actuators
Energy storage system
Wood processing machine (Homag)
Facilitator
Gains by DC-Smart-Grid
High robustness against power outage
Increased system efficiency by lower conversion losses
Flexible adjustments to the power systems
Additional drives
Storage capacity
Renewable generation
Application tests – DC-Smart Grid in productionScenario 4 – DC network for conveyance and palletizing.
Packmaschine und Schrumpftunnel
Rollfed
Etikett ierer
Streckblasmaschine
und Füllerblock
CIP-Station
Over 30 drives with rated power between 750 W and 22 kW
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Economic BenefitJust a control system? – Is there a business-case for Smart-Grids?
Facilitator
Fraunhofer IPA approach to industrial Smart GridsA Smart Grid joins hardware, control and business -case to maximize future benefit.
Economic benefit as main motivation!
… and technology as enabler.
Facilitator
Fraunhofer IPA approach to industrial Smart GridsPoss ible gains of decentrally controlled power systems and utilizing storage capacities .
Stabilization of internal energy supply system
Reduced costs by dynamic load management
Minimizing installed load capacities
Integration of volatile renewable generation
Compensation of reactive power by storage systems
Utilizing of recuperated energy
Increased reliability in case of failure
Facilitator
Fraunhofer IPA approach to industrial Smart GridsEnergy flexibility – Ability of a production system to adapt fast to changes in the energy market with low financial effort.
Quelle: Graßl, 2015
Changing energy source
Stopping process
Adapting machine utilization
Shifting order start
Changing sequence
Storing energy
Adapting process parameters
Changing shift time
Shifting break period
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Fraunhofer IPA approach to industrial Smart GridsPotential for cost reduction with flexible energy demand
Ener
gy p
rice
(€
/kW
h)
Cu
mu
late
d e
ner
gy c
ost
s (k
€)
Normal consumption Flexible load in a Smart Grid Energy price
Facilitator
The DC technology has the potential to increase
resource efficiency
energy efficiency
network stability
energy flexibility
Components are at an advanced stage of development or are already on the market
Fundamental paradigm shift is possible
Conclus ionDC Smart Grids are a key technology tosuccessfully implement the energy transition.
Facilitator
Vielen Dank!
Telefon +49 (0) 711 970 -
www.eep.uni-stuttgart.de
www.ipa.fraunhofer.de/de/Kompetenzen/effizienzsysteme.htmlHH
22.05.2019 |
Energy Efficiency and Flexibility – the Pillars of the German “Energiewende”
38
Raoul Laribi
M.Sc.
Institute for Energy Efficiency in Production (EEP)
Thank you!
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