Semi-physical Simulation Experiment System Of Fuel Control System For Small Turbofan Aero-engine

Digital fuel control system of modern aero-engine, which is of high control precision and easy to implement advanced control law, can highly improve the potential performance and statibility of the engine. From the very beginning to the end of the R&D of the fuel control system, plenty of experiments need to be carried out to confirm its accuracy, reliability and stability. However, experiments on engine and control system still in research could be of high costs and risks. In addition, not all the performance of the control system in the whole envelope can be tested in engine trial run on ground, nor do fault simulation and fault tolerance. The semi-physical simulation system, which has the advantage of the accuracy of practicality experiment and the safety and economy of simulation experiment, can do experiments in whole envelope and become a verification and evaluation method of the R&D of aero-engine digital fuel control system.To research the dual-redundancy digital electrical control system of a two-spool turbofan engine, a semi-physical simulation experiment system of fuel control system was designed and built. The main content of this paper includes:An unlinar real-time model was established with principle modeling method, based on the working principle of turbofan engine.The overall frame and subsystem of the semi-physical simulation experiment system was designed. The hardware platform includes fuel supply system, speed servo control system and measurement control system. The system can simulate high or low temperature(-55～100℃), positive or negative pressure(10-200kpa), engine rotational speed and the chamber pressure during the whole envelop. The software platform includes human-computer interface, engine simulation module and data communication interface.The semi-physical simulation experiment system was established and commissioned. Then semi-physical simulation experiment of control system of the turbofan engine was carried out, including steady state and dynamic process, such as starting, shutdown, acceleration-deceleration control process. The results show that the system runs well, and simulates the control process of fuel control system factually, which has certain guiding signifitance in the R&D of aero-engine digital fuel control system.