Cooperation between TenneT and Amprion

To carry out load flow forecasts in the operational planning phase and to identify possible congestions, which may also occur on interconnections, it is necessary to exchange data among TSOs. Therefore TenneT and Amprion have started the Security Service Centre which enables a better exchange.

Analysing system security by means of Day-Ahead Congestion Forecasts
The effect of neighbouring grids on the TSO’s own grid must be taken into consideration, even if the congestions are entirely internal, especially for contingency analysis purposes. Hence one of the main tasks is to organise this data exchange, to agree upon the preparation of data sets, and to ensure the confidential treatment of such data. The procedure for these Day-Ahead Congestion Forecasts (DACFs) is defined in such a way that each TSO can perform a reliable load flow forecast. The results and conclusions are supplied to the main Control Centre of Amprion TSO in Brauweiler (Germany) and TenneT’s National Control Centre in Arnhem (the Netherlands), so they can execute the secure transmissions.

Advising participating TSOs on the available transfer capacity
The process of capacity assessment involves TSOs determining how much cross-border capacity is available to the market. Especially in those parts of the Central European grid where congestion occurs on a regular basis, this capacity assessment process is crucial. Due to the changing pattern of trade, however, congestion may occur suddenly in any part of the grid. Capacity assessment must therefore cover every interconnection and every possible situation that may occur in the future. In view of the complexity of the transit flows and the interactions between the different areas, the capacity assessment process of the TSOs must be properly coordinated. The accuracy of the capacity assessment process depends on the availability of reliable information about each TSO’s grid system.

Advising participating TSOs on coordinated measures
The goal of these activities is to resolve foreseen congestions, and to advise the participating TSOs on the real-time resolution of unforeseen congestions during the day-ahead operational planning phase (from one year ahead to real-time operation). In this context, TSOs have to prepare and, if necessary, activate appropriate measures. Neighbouring TSOs will agree in advance on joint measures to deal with the identified congestions. Each TSO will take measures in its own system (e.g. topology or redispatch measures) in order to cope with congestion. If this is not sufficient, they will activate joint procedures with neighbouring TSOs.

Standardising and coordinating system security procedures and standards
By performing tasks in a joint SSC, TenneT and Amprion will achieve a higher degree of coordination and standardisation than if such tasks are performed by the individual TSOs. By using uniform input and aligned tools, the results will become more accurate and give better insight into the effects in the areas of the participating TSOs and other neighbouring TSOs.