The Equivalent Circuit in the Mobility Analogy of a Magnetostrictive Transducer in the Presence of Eddy Currents.
Abstract
Recent research into the highly magnetostrictive rare earth iron compounds has renewed an interest in magnetostrictive transducers. A typical magnetostrictive transducer is designed with the aid of an equivalent circuit which electrically represents the differential equations that govern the motion of the transducer. The equivalent circuit is used to predict the transmitting responses, receiving response, electrical impedance, and efficiency of the transducer. Ohmic losses generated by eddy currents in metallic magnetostrictive transducers reduce the efficiency and alter the electrical impedance. Thus an equivalent circuit is required which can predict the effect of eddy currents on the efficiency, the electrical impedance, the transmitting responses, and the receiving response of a magnetostrictive transducer. The report presents the derivation of an equivalent circuit of a magnetostrictive transducer in the presence of eddy currents using an exact eddy-current theory. However, use of the exact theory can be time consuming. Lumped equivalent circuits are also presented which use approximations to the exact theory to simply and accurately predict the efficiency and electrical impedance of a transducer with eddy currents within a frequency range of practical interest near the clamped characteristic frequency. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 26, 1979
- Accession Number
- ADA072879
Entities
People
- Steven W. Meeks
Organizations
- United States Naval Research Laboratory