VirTuOS is a research project funded by the BMWK that aims to establish a distributed test infrastructure for wind turbines (WT) at component level. As part of the project, a component test bench for testing the main converter of a WT is being developed and commissioned. The underlying idea is to replace parts of the overall system of the real WT by real-time simulations of the missing components.


Yoga Kannan © Copyright:


Yoga Kannan

Team Advanced Control Methods for Power Systems and HiL


+49 241 80-49581




Wind turbines are one of the key technologies for the success of the energy transition. Consequently, the share of wind energy in total electricity generation is steadily increasing. To ensure system stability, it is essential that wind turbines meet the requirements of the grid codes. Accordingly, it is necessary to determine the electrical properties for each new turbine type. In recent years, research projects such as CertBench have demonstrated that nacelle test benches are suitable for these tests. Compared to field tests, it reduces the time required and thus the associated costs. At the same time, the tests at system level increase both the flexibility and the reproducibility of the results. Nevertheless, they are associated with a complex mechanical test setup. In order to further reduce this effort, the test bench concept is to be reduced to component level. In contrast to previous tests on nacelle test benches, the load imposition on converter-based component test benches is purely electrical. Both the mechanical test bench and DUT components are completely omitted. The reduced complexity of the physical structure is compensated for by more complex real-time simulations of the emulated components. Finally, the simulated behaviour is to be imposed on the real interfaces of the DUT through a PHiL setup. The overall system behaviour is generated from the symbiosis of real-time simulations of the multi-physical drive train, real-time simulations of the electrical grid as well as the main converter of the WT as physical test item.

Test setup

An essential part of the project is the construction of a test bench in the megawatt power class at the Center for Wind Power Drives (CWD) at RWTH Aachen University, where the PHiL concept in combination with the test bench and the DUT will be experimentally validated.

Role of the ACS

Within the VirTuOS project, the ACS institute is significantly responsible for the development of the grid-side PHiL system. This requires the development and validation of suitable real-time capable grid models, advanced PHiL methods for coupling simulation and test bench as well as innovative control approaches that guarantee the necessary system stability and performance.

As a second main task, the ACS is investigating the possibility of a geographically distributed test setup in which, among other things, the simulation or parts of the simulation take place at locations that are geographically distributed. The VILLASframework developed at the ACS is used to couple the simulation with the PHiL system.

Project Partners Associated Partners
  • RWTH Aachen:

IRT - Institute of Automatic Control
PGS - Institute for Power Generation and Storage Systems
IEM – Institut für Elektrische Maschinen
AIA – Lehrstuhl für Strömungslehre und Aerodynamisches Institut

  Funding notice BMWK


This project was funded by the German Federal Ministry of Economics and Climate Protection under grant no. 03EE3079A.