International Conference on Power Engineering-2019 (ICOPE-19)

458 / 2018-12-30 22:46:39

Dynamic Simulation of Hybrid Power Micro Gas Turbine Systems

Solar energy; Distributed energy system; Dynamic model; MATLAB-Simulink; mGT

Plenary track > Advanced Energy Systems

Micro gas turbine (mGT) is a potential option for distributed energy systems driven by multiple energy sources, e.g. solar energy and/or natural gas. As to a concentrating solar power (CSP) generation system, air Brayton cycle system has advantages of compact structure, low water consumption and fast start-up. The dynamic performance of hybrid power mGT systems are investigated in this work. A dynamic model is built for a mGT (Turbec100) combined with a solar air receiver and a sensible thermal storage which are validated with experimental data. For steady state validation of mGT, the RMSE (Root Mean Square Error) of each compared parameters is smaller than 3.7%. For dynamic validation of mGT, the RMSE of rotational speed is 0.125% while the RMSE of combustor inlet temperature is 0.934% for power load increase. For air receiver, the RMSE of receiver outlet temperature is 2.5%. For thermal storage, the RMSE of final temperature for different positions is 3.7%. Finally, the dynamic responses of different mGT systems in stand-alone mode are carried out when power load and DNI change. Results show that the integration of solar receiver and thermal storage in mGT system can effectively reduce fuel consumption and realize energy storage and transfer. However, it will cause instability of system when operation condition changes. When power load decreases, heliostats are adjusted in time to cool down air receiver for the steady operation of system. When power load increases, it is essential to increase it step by step to avoid compressor surge. A mGT power generation system coupled with solar receiver and thermal storage is investigated for a whole day simulation which shows that thermal storage can reduce the fluctuation of combustor inlet temperature from 130.8 ℃ to 12.8 ℃, the system electrical efficiency is 24.1% and the average solar energy share of a whole day is 26.4% while the maximum solar energy share is 64.7%.