EVALUATION OF A THREE-PHASE DISTRIBUTION SYSTEM STATE ESTIMATION FOR OPERATIONAL USE IN A REAL LOW VOLTAGE GRID

The ongoing trend towards active distribution systems formulates a need to know the current state of the system. This information can be generated through a distribution system state estimation (DSSE). The accuracy of DSSE usually suffers from the lack of available measurements. In this paper a three-phase DSSE is performed for a real low-voltage system in Germany. The accuracy of the DSSE is evaluated based on the differences between the measurements and estimation results. Different measurement configurations are analysed, in order to determine a minimal measurement effort required for a given accuracy. Additionally, the optimal placement of new measurement devices is investigated. The results show that the performed DSSE is accurate enough to judge whether the operation of an unmeshed low-voltage system is within its thresholds or not.