Raczka, SebastianSebastianRaczkaHilbrich, DominikDominikHilbrichRehtanz, C.C.Rehtanz2025-11-032025-11-032025https://publica.fraunhofer.de/handle/publica/49805210.1109/PowerTech59965.2025.111806042-s2.0-105019321507The transition in energy systems from conventional, centralized power plants to distributed, renewable energy resources leads to challenges in the grids of the medium and low voltage levels. A wide-range integration of measurement and automation technology is cost-technically not feasible, but necessary for using conventional State Estimation algorithms. In this paper, an algorithm based on the Optimal Power Flow is presented, which determines the complex grid state vector by using a minimal amount of measurements. This approach has been shown robust grid state calculations with high estimation quality, without relying on pseudo-measurements, grid reduction methods, or artificial training.enfalseObservabilityOptimal Power FlowOptimizationPower Flow CalculationState EstimationOptimisation algorithm for under-determined grid state calculations in distribution gridsconference paper