Leary, Alex | Engineering Papers

DOE OSTI2024

Optical sensing of magnetic fields using magnetically sensitive materials

The invention provides a method for measuring the magnetic field of an electromagnetic component having the steps of: instrumenting one or more portions of an electromagnetic component by placing an optical fiber in electromagnetic communication with the one or more portions of said electromagnetic component; energizing the electromagnetic component; interrogating the optical fiber using light and an optical detector; and determining changes in the magnetic field incident on the optical fiber based on the detected changes in the light received by the optical detector.

Ohodnicki, Paul↗

NASA NTRS2020

Core Losses in Co-Rich Inductors with Tunable Permeability

High frequency, low loss power systems enable electrified aircraft propulsion. Filter inductors that reduce noise in high current systems can account for 50% of the motor drive mass. Efficient inductor cores with tunable permeability reduce system mass by producing less heat, that removes heat sink mass. Requirements for filter inductors vary based on the chosen topology, but all inductor cores must operate below saturation levels. As the saturation flux density is limited (less than ~2 T), high differential current applications require cores with low relative permeabilities. The large induced anisotropies possible in Co-rich metal amorphous nanocomposite materials enables gapless inductors with relative permeabilities down to ~20. These materials have fine grain size ~8nm with a faulted, close packed structure. The impact of different processing methods on core losses are presented along with comparison to other low permeability soft magnetic materials.

Leary, Alex↗