Operational control of wind farm clusters for transmission system operators

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Operational control of wind farm clusters for
transmission system operators

• B. Lange, M. Wolff, R. Mackensen, K. Rohrig
• D. Braams
• B. Valov, S. Heier
• L. Hofmann, M. Rosin
• C. Scholz, A. Könnemann
• K. Biermann

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Overview

• Wind Power as Power Plant
• Wind Farm Cluster Concept
• Wind Farm Cluster Management System
• Results of a Field Test
• Summary and Outlook

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Power generation of the wind power plant
Load profile wind generation 2015

• No conventional generation is running
• gt Grid management (congestion management,
  voltage control, ...) needed

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The system operators requirements on the wind
power plant

• Requirements for high penetration of wind power
  in the electrical supply system

• Production schedule / forecast
• Production limitation by load
• Congestion management
• Voltage control
• Balancing power provision
• Operational limits and fault behaviour

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The wind power plant capabilities

• Characteristics and capabilities of a modern wind
  power 'plant'

• Distributed generation / multiple grid connection
• Connection partly to distribution grid
• Weather dependent generation limit
• Generation forecast instead of generation
  schedule
• Pooling leads to higher forecast accuracy and
  less fluctuations

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Cluster definition

• Control system is needed to utilize the power
  plant capabilities
• Aggregation necessary
• Distributed generation
• Improved forecast
• Controllability of each grid node needed
• All wind farms connected to one grid node are the
  smallest unit for the system operator
• Cluster

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Wind Farm Cluster Control Concept
TSO Cluster Wind farm Turbine

• Hierarchical control system
• Control of clusters according to the requirements
  of the TSO
• Wind Farm Cluster Management System (WCMS)

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Wind Farm Cluster Concept
Cluster all wind farms connected to a
transmission grid node
Measurement and Forecast
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Control strategies

• Active power control
• Congestion Management
• Reduction of gradients
• Supply of balancing power
• Scheduling of wind power feed-in
• Reactive power control
• Supply of reactive power
• Voltage control

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Example Reserve power provision

• Planning of power and reserve power availability
  day-ahead

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Example Reserve power provision

• Provision of reserve power

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Wind Farm Cluster Management System (WCMS)
Weather forecast
WCMS
Measured values
Wind farm control commands
Grid calculation
Cluster forecast
Cluster controller
Clustercommands
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Forecast

• Wind power forecast for each wind farm is
  essential
• Aggregated to cluster forecast
• Dynamic forecast uncertainty
• Reduced uncertainty due to aggregation to cluster
• Forecast horizons
• Day-ahead for planning
• Short-term (0-8h) for operation
• Forecast method Mixture of experts

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Influence of the grid

• Direct grid connection
• Influence is calculated by the system online
• by grid calculation program
• Meshed grid
• Influence factors are calculated in advance by
  system operator

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Software with GUI
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Field Test
Substation Wechold
Wind Farm Mainsche/Pennigsehl33 WT / 60,4 MW30
MW controllable
Cluster Wechold 16 wind farmsabout 250 MW
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Field Test Active power control
Cluster available power
Cluster actual power
Cluster control setting
Penningsehl available power
Penningsehl actual power
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Field Test Effect of reactive power control

• Control of the cos j at the wind farm

leads to a voltage variation at the wind farm
connection of 2 kV
33 Enercon turbines - 60,4 MW
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Field Test Effect of reactive power control

• and of 1,2 kV at the 110 kV and 220 kV level at
  the substation Wechold

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Summary

• Integration of large amounts of wind power make
  new tools for grid operation necessary
• For integration of wind power, the Wind Farm
  Cluster Management System (WCMS) has been
  developed at ISET
• Provides forecast and allows control for each
  grid node
• Gives the TSO an extended control of the Wind
  Power Plant
• Its capabilities have been demonstrated in a
  field test in Germany

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Outlook WCMS in Spain and Portugal

• European research project Wind on the Grid
• WCMS demonstration in Spain and Portugal
• Additional hierachy level Wind farm operator

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Outlook WCMS demonstration at alpha ventus
Demonstration of WCMS planned with the first
German offshore wind farm alpha ventus As part of
the RAVE initiative
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Thank you for your attention !
Thanks for your attention! Visit ISET at Stand
7a316
Research partly funded by
www.iset.uni-kassel.de