Time-Domain Electromagnetic Characterization of Reaction Wheel for Space Applications

The electromagnetic characterization of reaction wheels is crucial to comply with the demanding ac magnetic field cleanliness requirements of space science missions, thus, preventing interference on sensitive onboard instrumentation. Therefore, a complete assessment, including the measurement of the magnetic flux vector at different operational modes and under dynamic conditions, is proposed as a contribution beyond conventional testing methodologies. This article investigates the worst-case magnetic field emissions experimentally, using a test setup based on a multichannel acquisition and multidomain postprocessing system. The focus of the measurement campaign was on the low-frequency range (10 Hz–2 kHz). Moreover, capturing the B-field in the time-domain enabled further analysis, that is, complementary outputs for understanding the electromagnetic performance of the reaction wheel. As a result, we can relate the wheel rotation with the current and the magnetic fields, compute the field orientation, and evaluate in-band interference for the magnetic field.