DESIGN, SIMULATION AND PROTOTYPING OF A LOW-SPEED PERMANENT-MAGNET DIRECT-DRIVE ALTERNATOR

Open Access
Author:
Yastishock, Daniel Evan
Area of Honors:
Mechanical Engineering
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Md Amanul Haque, Thesis Supervisor
  • Daniel Humberto Cortes Correales, Honors Advisor
Keywords:
  • alternator
  • generator
  • COMSOL
  • permanent-magnet
  • direct-drive
Abstract:
Losses in electrical generators due to gearboxes can be costly in terms of efficiency. However, the high speed at which generators run most effectively prohibits the generator being run without gearing. Exploration of design choices which could most effectively lead to a direct-drive solution provides a solution for a small-scale alternator. COMSOL Multiphysics simulation is used to compare design choices. A working prototype is then used to provide a performance comparison against the commercially-available alternator. This research showed that effective design choices such as magnet grade, magnet size, the amount of magnetic shielding, and whether or not the magnets were arranged into a Halbach array; all are able to increase the output of a permanent-magnet alternator at the cost of additional materials and assembly. A physical prototype confirmed the validity of magnet grade, magnet size, and shield size as a means of output up to 193% of root mean square voltage and up to 372% of root mean square power with root mean square voltage increasing to 162% root mean square voltage on average and root mean square power increasing to 264% on average.