Acoustic characterization of a stationary field synchronous motor

• Main Author: Woodward, E.C. Jr.
• Other Authors: Naval Architecture and Electrical Engineering and Computer Science
• Published: 2012
• Online Access: http://hdl.handle.net/10945/24382

CIVINS === The stationary field synchronous motor (SFSM) has been described and analyzed previously. This machine usually consists of a stationary, direct current field winding and a rotating, alternating current armature winding. The field winding is superconducting. This topology presents certain advantages and disadvantages. One of the greatest theoretical advantages is reduced acoustic emission. The precise nature of such reductions has not been considered in previous work. We investigate the gross acoustic signature of a notional stationary field synchronous motor utilized as a marine propulsion motor in a naval combatant using the following methodology: (1) model the forces (harmonic by harmonic) of electromagnetic origin using solutions of the two dimensional Laplace Equation arising from the scalar potential of a magnetic field, (2) Develop a force spectrum based upon this modeling, (3) Develop appropriate acoustic transfer functions describing the acoustic * propagation of the machine components, equipment mounting structures, and other pertinent items in the machine-to-sea sound conduction path, (4) Apply the force spectrum to the acoustic transfer function(s), and (5) obtain a meaningful far-field acoustic signature due to the SFSM.