Micro gas turbines (MGT) usually consist of the following principal components: compressor, recuperator, combustion chamber, turbine, generator with its associated power electronics and waste heat recovery system. All components interact with one another in a highly complex way, meaning that replacing one component influences all other components in different ways.
For example, if the pressure loss in the combustion chamber is reduced by swapping the burner for a modern one, a more compact and low-cost recuperator with higher pressure loss can be introduced, without compromising the plant’s output. Alternatively, the pressure loss saved can be dissipated by the turbine, influencing the operating point of the compressor and the gas temperatures in the cycle, and enabling a higher electric efficiency overall.
In order to examine the characteristics and dependencies of conventional and future micro gas turbine cycles and to develop and evaluate innovative new cycles, the department develops numerical simulation tools based on the programming languages MATLAB/Simulink and Fortran. The modular structure of the simulation tools allows a high level of versatility. According to the various measurement data gained from the test rigs in the department, the simulation tools can be validated and optimized.
Figure 2 shows the prediction of achievable efficiency increases through the improvement of the individual components of a micro gas turbine-based range extender for use in a car.
The simulation of an entire plant network consisting of an MGT, heat storage, consumers etc. enables the simulation and optimization of operating strategies. A possible use for this method could be the operative optimization of district heating plants depending on their load profiles. Such optimization should result in an increase in operating hours and a reduction in start-stop-cycles, shortening the amortization period and increasing the lifetime of the plant.
 Study on Range Extender Concepts for Use in a Battery Electric Vehicle - REXEL