Setup for Generating an AC Magnetic Field From 3 to 100 kHz

Generating a stable, homogeneous reference ac magnetic field is important for traceable calibrations of ac magnetic field analyzers with a triaxial coil probe (e.g., EFA 300, C.A. 42). These probes are widely used by health and safety professionals, in manufacturing, and in service industries. This paper presents a single-layer Helmholtz-type solenoid for generating the reference ac magnetic field in the frequency range from 3 to 100 kHz. Special attention is given to a full characterization of this setup, including a comparison between the analytical and finite element method design of the solenoid, on the one hand, and experimental results, on the other. The magnetic flux density inside the solenoid can be generated with expanded uncertainty of (0.4%–0.8 %) for $k=2$ using a special search coil.