Assessment of maximum distributed generation penetration levels in low voltage networks using a probabilistic approach

The main objective of network planning is to determine the technically and economically optimal solution that will ensure continuity of supply and adequate power quality as well as allow further integration of distributed generation (DG), despite its substantial impact on the network performance. The maximum DG penetration level also has to be planned or at least assessed, and is heavily dependent on the DG location and size and on the voltage control method. The paper presents a probabilistic approach to network planning, which has many advantages compared to the traditional approaches using estimated peak values and empirically defined simultaneity factors. The method enables the evaluation of the future voltage conditions and therefore the comparison of different network development scenarios, taking into account the stochastic natures of future DG location and loads consumption. By analyzing different solutions, it is possible to minimize the necessary investments in the network. The planning method is presented on an actual low-voltage (LV) distribution network, but it can be used also in medium-voltage (MV) network planning as well.