Improving Hybrid Electric Propulsion Efficiency

About this technology

Overview

Propulsion system engineers at NASA’s Glenn Research Center have developed a novel method for increasing the efficiency of electrically driven propulsors by improving the range of operability against stall. Stall affects both compressor and propulsion fans and can be induced from a variety of operational conditions, often transient in nature. The incidence of stall conditions requires an operating margin between the stall point and the point of optimum operating efficiency, and typically, the compressor/propulsor fan operates at a lower efficiency point to increase the stall margin. Stall must be avoided to maintain thrust and in some cases to avoid catastrophic failure. While many researchers have explored stall control in the past, it remains a prevailing issue. This innovation integrates supercapacitors in the electric drive such that the drive can quickly modulate power to avoid stall. The electric motor system can also enable improved stall detection.