Simulations of Brush Contacts of Homopolar Motor/Generators

A computational- simulation study of distributions of electric current and temperature in brushes and slip rings in two model homopolar- motor/generator configurations was performed in support of the development, by the U.S. Navy, of a superconducting homopolar motor/generator (SCHPMG) machine for ship propulsion. Electrical-contact performance (more specifically, brush/slip-ring contact performance) is a limiting factor in the performance of an SCHPMG machine. The present study and similar studies are needed to gain understanding of brush/slip-ring contact performance in order to enable optimal design of brushes for homopolar machines.