MCCS Voltcontrol

Six months in control center operations: MCCS VoltControl supports voltage management

As the power system evolves, voltage management is becoming increasingly complex. With more renewable energy sources being integrated into the system, conventional generation runs less frequently and is increasingly displaced from the market. This changes generation patterns, reduces the availability of traditional reactive power resources and makes voltage behavior more dynamic.

The Iberian blackout of April 2025 underlined the system-wide relevance of voltage management for secure system operation: according to the final report published by ENTSO-E (ENTSO-E 28 April 2025 Blackout), the event resulted from a combination of interacting factors, including gaps in voltage and reactive power control, differences in voltage regulation practices, rapid output reductions and generator disconnections.

In this context, Elia and 50Hertz have developed MCCS Voltcontrol as part of the MCCS programme. This challenge is further reinforced by the Belgian situation: from spring 2026 onwards, refurbishment works on the remaining nuclear generation units temporarily remove nuclear infeed from the system, increasing the operational relevance of voltage management.

MCCS Voltcontrol addresses this operational challenge by supporting operators during online operations. It continuously evaluates current grid topology and forecasted scenarios, predicts upcoming voltage situations and proposes optimal switching actions to keep voltages within secure limits.

The benefits of MCCS Voltcontrol are directly linked to the operational problems system operators face in voltage management:

• Managing a growing number of actions by identifying upcoming voltage issues and proposing suitable actions before limits are reached.
• Coordinating controllable assets by considering available switching actions and reactive power resources to support the voltage objective.
• Assessing reactive power needs by evaluating demand and available potential in the grid.
• Reducing operational complexity by translating forecasts, constraints and available assets into actionable recommendations.

Classical optimization algorithms are the technical core behind these capabilities. They combine real-time operational data, grid topology, forecast information, system constraints, available switching actions, reactive power resources and controllable assets, and an objective function to assess current and future voltage conditions. Based on this assessment, the system predicts upcoming voltage issues and proposes or directly activates optimal switching actions to keep voltages within secure limits. Over time, it learns from previous decisions and can progressively automate more of the voltage-management workflow.

This October marks six months of MCCS Voltcontrol supporting real-time voltage management at Elia’s National Control Centre in Brussels, following its introduction in April 2026. Building on this operational experience, 50Hertz will introduce the same decision-support approach into its own control-centre environment to support increasingly complex voltage-management decisions.

Find out more on the MCCS Voltcontrol on the product page.