Online Monitoring and State Estimation

Online Monitoring is an app in the Operation Management area of the Intelligent Grid Platform. The app delivers information about the current grid state based on real-time measurement data. The focus is mainly on the medium and low voltage level, making the app a helpful addition to the control system.  

The topological grid model and all available measurement values in the grid (e.g. readings from stations, smart meters or generators) are used for the calculation. State estimation is used to determine the grid state. It is a complex numerical procedure, that is used to estimate the current grid state, while taking into account measurement errors and the minimization of error tolerances of measurement devices. 

The state estimation originated in the transmission grid, which is usually comprised of many (partially redundant) measurement points. The limited number of readings in the medium and low voltage grid leads to an underdetermined system and to an increasing number of assumptions needing to be made about the supply task. 

The app Online Monitoring enables information about the grid utilization, while considering the current topology (live switching states and current tap changers can be integrated). The grid state is visualized in real time and automatic warnings are sent in the case of limit value violations. The results are updated by the minute based on new live measurement data.