A three-dimensional risk matrix to support investment strategies for network planning by analyzing the impact from congestion on the remaining lifetime of assets

Reinforcement to increase the capacity of distribution networks is necessary to prevent congestion if the load exceeds the capacity limit of assets. However, distribution system operators (DSOs) face difficulties in keeping up with the pace of all required reinforcements due to the energy transition. Therefore, this paper proposes a new framework for DSOs to support their investment strategy for network planning that can indicate for which assets reinforcement is most urgent and for which congestion management (CM) is sufficient. This new framework is based on a three-dimensional risk matrix which distinguishes three levels to categorize the impact of congestion on the fault probability. Three properties are used to reflect the dimensions of the risk matrix which are the maximum power, frequency, and maximum duration of the congestion. Two use cases to which the proposed framework is applied are presented in this paper. First, both use cases are studied without CM. Then, the use cases were studied with the application of CM. For both use cases, the results indicated that the application of CM can not avoid the need for reinforcement.