Hardware-in-the-Loop Power Extraction Using Different Real-Time Platforms

Aircraft power demands continue to increase with the increase in electrical subsystems. These subsystems directly affect the behavior of the power and propulsion systems and can no longer be neglected or assumed linear in system analyses. The complex models designed to integrate new capabilities have a high computational cost. Hardware-in-the-loop (HIL) is being used to investigate aircraft power systems by using a combination of hardware and simulations. This paper considers three different real-time simulators in the same HIL configuration. A representative electrical power system is removed from a turbine engine simulation and is replaced with the appropriate hardware attached to a 350 horsepower drive stand. Variables are passed between the hardware and the simulation in real-time to update model parameters and to synchronize the hardware with the model. Real-time simulation platforms from dSPACE, National Instruments (NI), and The MathWorks' xPC are utilized for this investigation. Similar results are obtained when using HIL and a simulated load. Initially, noticeable differences are seen when comparing the results from each real-time operating system. However, discrepancies in test results obtained from the NI system can be resolved. This paper briefly details the underlying problem and its solution before discussing test results which show that dSPACE, NI, and xPC can be configured to match the baseline Simulink data.