Hybrid power plants consisting of SOFC and gas turbine promise high electrical efficiencies. The German Aerospace Center aims to build and operate such a hybrid power plant with an electrical power output of 30 kW. The presentation will illustrate the general concept of the power plant and give an overview of the current status of the project.

A hybrid power plant system concept based on a 30 kW el solid oxide fuel cell (SOFC) and a 3 kW el micro gas turbine (MGT) has been developed at the German Aerospace Center (DLR). At the Institute of Combustion Technology, a test rig with a MGT and emulated SOFC has been built, in order to investigate the effects of each system on the other, and to validate the concept of the hybrid power plant before coupling the systems. A control strategy for the emulator test rig has been elaborated and tested to allow for system operation at all expected load points. Different control loops based on PI and PID controllers have been parametrized and successfully tested. A turbine outlet temperature (TOT) controller with a feed-forward element was implemented and good performance during transient maneuvers has been shown. Start-up and shutdown routines, as well as an emergency stop maneuver, have been tested and integrated into the test rig state machine.

Hybrid power plants consisting of a gas turbine coupled with solid oxide fuel cells (SOFC) convert chemically bound energy into electrical energy. They can be operated at higher electrical efficiencies than conventional power plants. Theoretical studies suggest electrical efficiencies of up to 70 %. The German Aerospace Center (DLR) aims to build and operate a hybrid power plant with an electrical power output of 30 kW. The system concept and design of the power plant have been finalized and the specification of all major system components has been carried out. Currently, different system components are being purchased and tested. The presentation gives an overview of the current status of the project and illustrates the general concept of the power plant. All major components of the power plant are described. Important specifications and characteristics of the components are presented. Results of component tests are presented where available and the expected operating range is specified.

A hybrid power plant consisting of a micro gas turbine (MGT) and a solid oxide fuel cell (SOFC) is a promising technology to reach the demands for future power plants. DLR aims to set up a MGT/SOFC hybrid power plant demonstrator based on a 3 kWel MTT EnerTwin micro gas turbine and an SOFC module with an electrical power output of 30 kWel from Sunfire. For the detailed investigation of the subsystems under hybrid conditions two separate test rigs are set up, one in which the MGT is connected to an emulator of the SOFC and vice versa. The paper introduces the set-up and the functionalities of the MGT based test rig. The special features are highlighted and the possibilities of the cyber physical system for emulation of a hybrid system are explained.