Modern power grids face a multitude of challenges, including substantial fluctuations and the decentralized and patchwork generation of power. The system is sensitive: Even the smallest ups and downs can be detected over long distances. Like in March 2018, for instance, when clocks across Europe suddenly started running slowly . The cause for this was a supply shortfall on the European electricity market, stemming from the on-going political dispute between Serbia and Kosovo.
Scientists at Jacobs University in Bremen have now been able to prove that the increase in feed-in of renewable energies leads to more widespread failures, and how – and that some networks are better at mitigating this than others. The researchers were surprised to discover that distribution networks structured like a tree are more robust than close-meshed integrated networks. They had expected to see the opposite: “Because a tree structure has far more distinct and hierarchical connecting lines than a circular network with its multitude of meshes and loops,” says Prof. Stefan Kettemann . The reason for this observation are the different frequencies of the two networks. In the case of close-meshed integrated networks, the larger the network becomes, the lower the resonance frequencies become. In networks structured like a tree, they remain at the same level – which makes the networks less prone to failure.