Model Predictive Control Study for an Electrified Turbofan Engine

Brittany Nez; Joseph Connolly

NASA NTRS · 20210021166

Model Predictive Control Study for an Electrified Turbofan Engine

Abstract

A control sensitivity study is conducted for electrified aircraft propulsion concepts using a publicly available turbofan engine simulation. A Proportional-Integral (PI) controller serves as a baseline for comparison against an advanced Model Predictive Control (MPC) approach. MPC is used in the control scheme to allow for subsystem coordination of engine and electric power loads. The electrified turbofan engine includes electric machines to augment the amount of torque being applied to the spools of the engine during transient phases of operation. Power augmentation allows for energy to be stored or exhausted in a manner that increases the fuel efficiency of the engine, reducing aircraft emissions and noise. The study compares the fan speed, high pressure compressor stall margin, and low pressure compressor stall margin against the baseline PI control system, an MPC system without electric machines, and an MPC system with electric machines. The MPC system with electric machines is optimized using the sample time, control horizon and prediction horizon. The MPC design provided a stable damped response as desired and allowed operability margins to be maintained

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Brittany Nez, Joseph Connolly. Model Predictive Control Study for an Electrified Turbofan Engine. https://ntrs.nasa.gov/citations/20210021166

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