Discussion of Test Results and Possible Domestic uses of Commercially Available Micro- Permanent Magnet 3-Phase Generator

Abstract

This paper discusses the technology and possible uses of a Micro–Permanent Magnet 3-phase alternator that is commercially available. These tiny rotating machines can deliver a few Watts of electric power and can be used to power small electronic appliances and devices in the home. These alternators or generators can be utilized particularly in rural areas where homesteads are typically off-grid or in urban areas where customers may suffer from lack of available power during load-shedding. The aim of this paper is to highlight the importance of permanent magnet AC generators. To this end a small commercially available machine was inspected and tested with the intention of reviewing the internal components and estimating some parameters like the Winding Factor and Air-gap Flux resulting in the appropriate generated voltage. The paper also investigates the generated voltage at different shaft speeds and loads. The open-circuit and full-load tests are also performed. The paper also looks at ways in which losses can be reduced and the output power can be optimized. It is noted that such generators are suited to relatively slow shaft speeds that could be provided by steady streams of water, wind-power and other direct-drive mechanisms like motors found around the home. These machines have simple construction consisting of rotating and fixed components made from relatively inexpensive metals and could be candidates for manufacture on the African continent using indigenous materials. Finally, a brief discussion is introduced related to the manufacture and production of such a machine and the possible demand constraints in the current economic climate.