Improved grid protection in power converter-dominated networks

Project state
Decentralised power generation plants such as photovoltaic systems and wind turbines require new approaches for protecting the grid.
Decentralised power generation plants such as photovoltaic systems and wind turbines require new approaches for protecting the grid.
Image: Fotimmz -

An increasingly decentralised energy production requires new technologies for effective grid protection in the distribution grids. The aim of the "Grid protection in power converter-dominated networks" (NEDO) research project is to determine the requirements for grid protection with a high proportion of decentralised infeeds. The focus is on power converter-coupled generators such as PV systems. The project is being carried out at Fraunhofer IWES in Kassel. The project manager for the NEDO project is Wolfram Heckmann.

The energy transition in Germany will see increasing amounts of electricity fed into the German electricity grid from decentralised generation systems. This energy is generally produced by renewable energy sources such as the sun or wind. Their intermittent production and decentralised locations – the generators are not located in the vicinity of the largest loads but at places with the best weather conditions – present the grid with new challenges.

In order to identify changes in the distribution system, based on the grid protection requirements and with a high proportion of decentralised infeeds, the researchers are focussing on two main aspects in particular: on the one hand they want to record the short-circuit current contributions of commercially available converters for different fault types and process these for use in planning and calculating grids computing; on the other hand they want to investigate the feasibility of a new method for compensating for earth fault currents and depict their impact on the grid and system operation.

The initial findings are expected at the end of 2015.

Project duration

08/2014 – 01/2017


Wolfram Heckmann
Project coordinator
Fraunhofer-Institut für Windenergie und Energiesystemtechnik (IWES)
Bereich Anlagentechnik und Verteilungsnetze
Königstor 59
34119 Kassel, Germany

Basic information

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