The transformation of the electrical power supply in Germany, which is commonly referred to as energy conversion, is characterized by the transition of a system with central generation within large power plant units with approx. 1 GVA electrical power to a System in which the generator units are arranged smaller and decentralized. These small and medium-sized generation units (wind, photovoltaic, CHP) and storage of subscriber lines in the area up to 10 MVA are almost exclusively connected by power electronic systems (inverters, especially “Active Infeed Converter”, shortly AIC) to the medium- and low-voltage network.
In this project mainly technical questions are addressed. These questions mainly arise from the fact that the stability and the quality of the supply is not determined by the intrinsic behavior of large machine sets (overload capacity, mass inertia), but by the behavior implemented in the inverter in the case of a large number of decentralized generating units connected via inverters. As a limiting case, one can start from the idea that the grid is fed exclusively by inverter-coupled generators.
The overall objective of the project is to develop and test methods for the stable operation of a power supply network in a multitude of decentralized consumers connected via inverters to ensure a high supply quality and reliability.
Scientific work
- Investigation of the effect of the islandization of distribution networks in the medium and low voltage range on grid stability
- Further development of methods for determining the network impedance
- Investigation into how measuring signals of the used converters can be used to observe the network. Subsequently, it will be examined how this can be used to detect, for example, faults in the network, or a transition to the islands network
- Examination of decentralized algorithms at the converter level. These are aimed in particular at the basic frequency voltage and current control at the outputs the converter
