Mitarbeitende

The future electrical grid will be driven by an increasing amount of power electronic (PE) driven power sources such as photo voltaic plants. Therefore, the dynamics and stability of the grid is heavily influenced by the related PE-controllers of grid connected inverters.

Current research activities

The current main research focus is to analyse and develop different controllers for grid connected inverters, that can act independently and decentral with unknown grid impedance.

Past research activities

Flywheel Energy Storage Systems (FESS) are an interesting way to balance the power in the grid. The main principle is to connect an electrical machine with high inertia via two back-to-back inverters to the grid (figure). Depending on the demand of the grid operator, energy can be transferred between the grid and the FESS (when the speed of the motor is high enough). In relation with the KoREV2 project, a power controller was developed to manage the described energy transfer in conjunction with providing a stable DC link voltage. To achieve a high dynamic behaviour, an eigenstructure assignment controller was used.

Furthermore, a controller for balancing the DC link of the two used three level back-to-back inverters was developed.