Publication of system protection plan

The joint system protection plan of the four German transmission system operators describes a framework with an overview of emergency measures and their necessity. The aim of the system protection plan is to remain capable of acting in critical emergency situations in order to maintain grid and system security in the synchronous area.

The basis for the measures described is Section 13 EnWG. The measures are activated in accordance with the "Commission Regulation (EU) 2017/1485 of August 2, 2017 establishing a guideline for transmission system operation" (System Operation Guideline).

The system protection plan refers to the applicable standards of the VDE application guidelines at relevant points. This includes VDE-AR-N 4140 (Cascade) and VDE-AR-N 4142 (Automatic final measures).

The requirements defined here therefore apply equally to TSOs, distribution system operators (DSOs) and significant grid users (SGUs) in all German control areas. This means that TSOs, DSOs and SGUs are obliged to comply with the requirements and implement the stipulations within the set deadlines. The status thus achieved must subsequently be maintained by the respective grid operator and grid users.

History of changes:

The system protection plan was revised by the TSOs in 2020 with the aim of clarifying final measures.

The following points have changed significantly compared to the original version:

• For reasons of completeness, the system protection plan of the four German transmission system operators describes not only the final measures but also other measures that are necessary to comply with system security and the requirements of the NC ER. However, the German TSOs already activate some of the measures listed in the NC ER grid code in the normal or endangered state, as these are based on contractual agreements in the German transmission grid.  For this reason, manual and automatic final measures, which are assigned to the emergency state and thus to the SSP, are now marked in the document with a red frame. In addition, the final measures of the system protection plan are listed in an overview table in Annex 1.
• The reference value for the power to be switched off in Germany as a manual final measure in the event of an underfrequency/power shortage situation was changed from 1.5 * ACE to ACE + 500 MW. (Chapter 7.1.1) [ACE: Area Control Error].
• Chapter 8.3 Concept for automatic prevention of voltage collapse specifies that at least one of the measures described must be implemented. This is in line with the requirements of VDE-AR-N 4142 (Automatic final measures) and the NC ER. In the old version of the system protection plan, however, the wording was unclear and could have led to the misinterpretation that all defined measures had to be implemented.
• Minor formal changes were also made.