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Reliable intelligent power grids

Procedures to model grid behavior and for safe data transmission within smart grids

PTB-News 2.2018
Especially interesting for

digitalization of the energy transition

digital sensor networks

The more power that is generated by regenerative energy sources, the more complex the power grids become. This makes it ever more important to set up intelligent power grids where producers, consumers and measurement points communicate with each other. Within the scope of an EU project, mathematical modeling procedures have been developed to make the behavior of power grids more predictable and to create secure cryptographic methods.

The large number of suppliers and the fluctuating power supply from regenerative sources have transformed power grids into excessively complex systems. It has thus become ever more important to create “intelligent” power grids. In a socalled smart grid, intelligent power meters and other communicating elements ensure a constant exchange of information. It is the only way for suppliers and consumers to adapt their behavior to the current situation on the power market if need be. With the increasing levels of communication, it has become more and more important to ensure secure data transfer.

Owners of small-sized wind power, photovoltaic or CHP facilities do not often feed the power they produce into the high-voltage power system; instead, they feed it into the lower-level power grid, namely into the medium- or low-voltage grid. Too few measurement points are however available there to monitor grid behavior with sufficient accuracy.

Within the scope of the GridSens EU project, PTB, with several partners, has developed new mathematical methods to enable the current, the voltage and the phase angle to be predicted in mediumand low-voltage power grids. Both the time-dependent progress of the measured values and the fact that the characteristic of the current conductors might not be sufficiently known were taken into account. Applied to real grid data, it has been possible to demonstrate that the procedure could be used in practice.

To find out whether and how this procedure for the secure transmission of measurement and operating data could possibly influence the response speed of the measurement points, a test network including all the necessary infrastructure for secure data transmission was set up at the Energieforschungszentrum Niedersachsen (EFZN – Lower Saxony research center on energy). A newly developed generic model for the end-to-end protection of the data transfer has been implemented in the prototype of an intelligent measurement sensor. It has shown that the protection goals consisting of integrity, authenticity and privacy are achievable without the response speed being significantly influenced.

More reliable methods for the reconstruction of the grid state for typical medium- and low-voltage grids and validated procedures for the secure transmission of measurement and operating data are thus available.


Sascha Eichstädt
Presidential Staff
Phone: +49 30 3481-2008
Opens window for sending emailsascha.eichstaedt(at)ptb.de

Scientific publication

S. Eichstädt, N. Makarava, C. Elster: On the evaluation of uncertainties for state estimation with the Kalman filter. Meas. Sci. Technol. 27, 125009 (2016)