In a nutshell
- For the first time nationwide uniform planning principles for high-voltage networks
- Planning horizon greater than ten years
- Application of the NOVA principle: network optimisation before reinforcement and expansion
- (n-1)-safe planning: failure of a piece of equipment must not lead to inadmissible operating condition
The VDE-Application Rule "Planning principles for 110 kV networks" (VDE-AR-N 4121) defines for the first time nationwide uniform procedures and assumptions for the planning of high-voltage networks. The Application Rule lays down important principles for planning and thus facilitates the work of network operators. Each network operator is responsible for the concrete implementation and economic optimization of the network and its operation.
Focus on long-term planning
The Application Rule focuses on the technically and economically sustainable planning of high-voltage networks with a planning horizon of more than ten years. The main steps of the planning process are described as well as the principles behind them.
The grid is dimensioned based on forecast developments in load and generation. If the planning shows that the supply is at risk, measures are implemented according to the NOVA principle: first, an attempt is made to optimize the grid (e.g. by switching circuits) before the grid is reinforced (e.g. changing cables) or expanded as a last measure.
The aim of planning is to ensure that the failure of a piece of equipment does not lead to inadmissible operating conditions under any circumstances. This planning principle is called (n-1) safety. In addition, special failure scenarios are defined in the Application Rule, for which even the simultaneous failure of several pieces of equipment must be considered.