Congestion management


The increasing share of generation from power plants based on renewable energy sources as well as the further integration of European markets for electrical energy lead to to a higher need for transmission capacity in the transmission and distribution grid. In this context, remedial measures to relieve congestions are increasingly required in order to enable transmission capacities while at the same time ensuring grid security.

With the methods developed at the IAEW, we identify the need for market and network-related remedial measures for future scenarios. The measures that are used for this purpose include

  • Redispatch of conventional power plants,
  • Feed-in management,
  • Topology optimization,
  • High voltage direct current transmission systems
  • and other power flow controlling equipment.

Depending on the application, time-discrete or time-coupling calculations can be performed to prioritize the different solution options.

In particular, when determining the necessary bottleneck elimination measures, measures for the optimised utilisation of the transmission network such as overhead line monitoring, the use of active power flow controlling equipment and reactive network management can be taken into account.

For active power flow controlling equipment, detailed models exist for high-voltage direct current transmission systems, phase shifting transformers, thyristor controlled series capacitors (TCSC) and static synchronous series compensators (SSSC). The models developed at the IAEW also enable a detailed consideration of different design options for reactive network management, in which, for example, limited areas of intervention of congestion measures and line-specific temporary overload capacities can be taken into account.

The focus is on the German transmission grid, with particular attention being paid to the regulatory framework (e.g. flexibility market, Clean Energy Package, nodal pricing), but other countries and cross-border approaches are also possible. The increasing challenge of coordination with subordinate network levels is taken into account with cascaded approaches, both in simulations and in real-world laboratories.