(Frankfurt a. M., 28.09.2023) The discussion about the expansion of the power grid has so far focused primarily on the lengthy and costly construction of new routes and lines. The massive and accelerated expansion of renewable energies on the generation side and electromobility and heat pumps on the consumer side are increasingly causing distribution grids to operate at capacity limits. This threatens bottlenecks in the distribution grids and grid operation management is becoming increasingly complex. In a new study, the Power Engineering Society within VDE (VDE ETG) now concludes that the increasing complexity and growing challenges can only be overcome with active grid operation and via automation.
Active network operation instead of passive-reactive
The operation of low- and medium-voltage networks currently mostly follows a passive-reactive approach. In the study "High automation of low and medium-voltage networks", the experts from VDE ETG also use many examples to show how automation can make better use of existing network capacities and increase the efficiency of network operation. For example, by automatically restoring the supply if there is a power outage in an area, e.g. due to extreme weather conditions. Or how active grid operation can integrate more photovoltaic systems or electric cars into the grid more quickly, because the power flow can be influenced as needed when bottlenecks threaten. Another example is system services such as frequency or voltage maintenance, which can be provided more easily with new software solutions or better data exchange.
"Complexity has now reached a level that requires extensive assistance systems and automation functions in distribution networks," explains Dr.-Ing. Sönke Loitz of Netze BW and head of the VDE ETG Task Force, which prepared the study on the high automation of low- and medium-voltage networks. "Only in this way can network management master the complexity and implement the necessary tasks and decisions," Loitz continues.
Observability and controllability - two core elements of automation
Nevertheless, there are currently only a few automation solutions in the low- and medium-voltage grid in Germany that go beyond a pilot character. "The aim of the task force was therefore to clearly highlight the added value of automation in low and medium voltage grids and to make recommendations for action for the various players in the environment of (highly) automated grid operation," says Dr.-Ing. Karsten Viereck from Maschinenfabrik Reinhausen, who accompanied the task force as a mentor from the VDE ETG board.
Currently, our medium and low-voltage networks are usually only observable or controllable to a limited extent. Condition monitoring, i.e., making the networks observable while maintaining all necessary measures to ensure cyber security, is an essential component of automation. In addition, against the backdrop of the electrification of the heating and mobility sectors and the integration of electrical storage systems, the controllability of operating equipment, such as remote switching, is essential for the realization of automation solutions.
The right technology is needed and the regulatory framework must be right
In particular, if active network management is increasingly sought in the low- and medium-voltage networks, demand-oriented automation is required due to the large number of low- and medium-voltage networks. The VDE study shows a practical path of action towards a highly automated distribution network and at the same time identifies further requirements and research needs. In addition to enabling active grid operation by changing the regulatory framework accordingly, it is also necessary to ensure that this type of grid expansion is not financially inferior to conventional grid expansion. At the same time, framework conditions must be created in which, for example, remote software updates are permissible without having to recheck the functions of the plants on site. Operating processes must also be automated, for example, to improve the data situation and data quality. And last but not least, the transformation of the low and medium-voltage networks must also involve the employees, e.g., through appropriate qualification measures.
The VDE ETG study "High automation of low and medium voltage networks" is available for download here (German version).