Abstract
The author previously developed an ac magnetic measuring system using magnetic fluid. However, he was unable to obtain a simple and general criterion or an instrumental method for measuring the ac primary permeability of magnetic fluid, because of its special characteristics, such as low permeability and liquidity. This paper proposes a method for instrumentation with complex magnetic permeability of the magnetic fluid in the high frequency band. The method is simple and convenient in comparison with the conventional ac test method. It is obtained by pouring several types of magnetic fluid into a 1-turn-type annular container, using an impedance material analyzer. The complex magnetic permeability was measured from 10 kHz to 1.8 GHz. The experimental results show the effectiveness of this method of instrumentation.
