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Frequency Containment Reserve

Activation of Frequency Containment Reserve

The activation of FCR occurs linearly with the deviation from the nominal grid frequency of 50.0 Hz. Unlike other types of balancing services, the activation of FCR is decentralized and solidaristic throughout the entire continental European synchronous area.

The activation of FCR is decentralized because:

  • TSOs do not operate a call-off system for FCR.
  • each awarded technical unit independently and locally measures the grid frequency.

This makes FCR a distributed, very robust type of control power.

The activation of FCR is solidaristic because:

  • consideration is given only to the grid frequency deviation, not which TSO in Europe is responsible for it.
  • all technical units in continental Europe participating in FCR help to stabilize the grid frequency.

This allows large disruptions to be collectively mitigated. Disruptions can either lead to a power surplus or a power deficit. In the case of a power surplus, the grid frequency rises above the nominal frequency of 50.0 Hz, while in the case of a power deficit, the grid frequency falls. To stabilize the frequency deviation, negative FCR is needed for a power surplus, and positive FCR is required for a power deficit.

In the case of a frequency deviation outside the deadband, FCR providers must deliver FCR within a maximum of 30 seconds. The deadband of 49.99 – 50.01 Hz avoids unnecessary frequent switching between positive and negative provision. Within the deadband, providers do not need to deliver FCR.

Even during extreme frequency deviations, providers must meet the technical requirements. Specifically, when there is a frequency deviation of ±200mHz from the normal frequency, the participating technical units must deliver the entire FCR within 30 seconds. The power output of the technical units is linearly increased or decreased and maintained for up to 15 minutes.

The technical units operate a proportional controller (P-controller) locally to deliver the FCR. These P-controllers cannot bring the frequency deviation back to zero, but they ensure that the frequency deviation is stabilized. The use of FCR to stabilize the frequency results in an imbalance.

It is up to the responsible TSOs to restore their balance deviation by using different balancing services, such as aFRR and mFRR, so that the grid frequency can return to normal and the FCR is available again for new disturbancesEs ist an den verursachenden ÜNBs ihre Bilanzabweichung mittels anderern Regelleistungsprodukten Regelreserven, wie aFRR und mFRR, wieder gerade zu stellen, so dass die Netzfrequenz sich wieder normalisiert und die FCR für neue Störungen wieder bereitsteht.