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Henry B Fain

Publications and source records attributed to Henry B Fain.

Nasa Scaled Power Electrified Drivetrain

A new transportation system is upon us, and it aims to satisfy the increasing need for air transportation. Advanced Air Mobility (AAM) has the potential to connect cities and increase air transportation capabilities and services. NASA recognizes that there is a need for standards and technology development to ensure the safety and reliability of future AAM aircraft. The NASA Revolutionary Vertical Lift Technology (RVLT) Project is using testbed data to satisfy these needs. One of these testbeds is the Scaled Power ElEctrified Drivetrain (SPEED). SPEED is a 400 VDC, 6 kW continuous, electrified aircraft propulsion system which is used to calibrate equipment, develop procedures, and perform tests at a reduced power level. This paper describes the testbed and the work it has supported at NASA.

Patrick A Hanlon↗

The NEXT-C Power Processing Unit: Lessons Learned from the Design, Build, and Test of the NEXT-C PPU for APL's DART Mission

NASA’s Double Asteroid Redirection Test (DART) will be the first-ever planetary defense mission to demonstrate asteroid deflection using kinetic impactor technology. The DART spacecraft will utilize the NASA Evolutionary Xenon Thruster (NEXT), which is a successor to the NSTAR ion propulsion system that successfully propelled NASA’s Deep Space 1 and Dawn spacecraft. In 2015, NASA partnered with Aerojet Rocketdyne and ZIN Technologies on the NEXT-Commercial (NEXT-C) effort to manufacture a Flight-Qualified (TRL 8) power processing unit (PPU). The NEXT-C PPU was based on the heritage gridded ion thruster PPU from NSTAR and NEXT, but with significant improvements in performance and manufacturability. The design goals of the NEXT-C PPU were to achieve the technical performance goals of the PPU in size, mass, and efficiency over a wide range of input voltage and output power. This paper discusses the lessons learned from the design, build, and test of the NEXT-C PPU, and how challenges were overcome to deliver a Flight PPU.

NEXT-C↗

Investigation of Rectifier Diode Failures in the NEXT-C Power Processing Unit

NASA's Evolutionary Xenon Thruster-Commercial (NEXT-C) project is tasked with developing flight electric propulsion systems, including both thrusters and power processing units (PPUs). In 2018, the beam supply in a NEXT-C engineering prototype PPU experienced an output rectifier diode failure during development thermal-vacuum testing. A failure investigation led by NASA GRC identified the root cause of the failure as a thermal runaway caused by increased reverse recovery losses in the diodes when the PPU was run at its maximum operating temperature. Significant reverse recovery performance variations were identified in diodes with the same part number but manufactured by different vendors. The failure investigation was able to collect evidence of the increased reverse recovery and replicate the diode failures in a controlled laboratory environment.

George L Thomas↗

NASA Advanced Reconfigurable Electrified Aircraft Laboratory (AREAL)

The rapid maturation of electrified aircraft and the underlying technologies has outpaced the development of corresponding standards and guidelines. This is especially true with respect to the design and test of high voltage power systems and equipment. To expedite the development of these standards and guidelines, the National Aeronautics and Space Administration (NASA) Revolutionary Vertical Lift Technology (RVLT) Project has designed and built the Advanced Reconfigurable Electrified Aircraft Laboratory (AREAL). AREAL is a 200 kW High Voltage DC (HVDC) test facility that can be reconfigured to test various electrical power system (EPS) architectures and/or different types of Utilization Equipment (UE). This paper will cover AREAL and its capabilities, the testing planned within AREAL, and how the tests performed within AREAL will inform developing HVDC Power System standards, test methods and guidelines, and models.

Aerospace↗