Integrated Aircraft Electrical Power System Modeling and Simulation Analysis 2010-01-1804

Advancements in electrical, mechanical, and structural design onboard modern more electric aircraft have added significant stress to the electrical systems. An electrical system level analysis tool has been created in MATLAB/Simulink to facilitate rapid system analysis and optimization to meet the growing demands of modern aircraft. An integratated model of segment level models of an electrical system including a generator, electrical accumulator unit, electrical distribution unit and electromechanical actuators has been developed. Included in the model are mission level models of an engine and aircraft to provide relevant boundary conditions. It is anticipated that the tracking of the electrical distribution through numerical integration of these various subsystems will lead to more accurate predictions of the bus power quality. In this paper the tool is used to evaluate two architectures using two different load profiles. In the first architecture conventional power resistors in the actuator electronic units are used for dissipation of regenerative energy. The second architecture makes use of a previously designed electrical accumulator unit to handle the peak and regenerative power created by the electromechanical actuators. The first load profile was within the design space of the electrical accumulator unit; whereas, the second load profile was found to be beyond the design space for the electrical accumulator unit. Transient evaluations and energy metrics were used in evaluating capability of the two architectures. As expected, for the first load profile the architecture with the electrical accumulator unit improved the power quality of the electrical system. Using the second load profile, the architecture using an electrical accumulator unit showed degradation in electrical bus stability, and did not improve the overall energy usage of the aircraft. Changes either to the control of the electrical accumulator unit, the actuator, or the flight control may be required to better make use of the electrical accumulator unit. The paper intent is to begin the evaluation of an integrated electrical system with an electrical accumulator unit and not necessarily fully evaluate electrical accumulator unit technology.