To get free from the risks that arise from price variations of rare-earth metals, an alternative current generator for motorcycles was developed using conventional ferrite magnet while keeping the same amount of electricity generation as that of using rare-earth metal. For the application of ferrite magnet to a motorcycle, the way of having a larger size cannot be allowed because of the increases of the mass and moment of inertia associated with that. Accordingly, in our development, the increase of electricity generation was realized by changing the current control from regulated short-circuit rectifier method to phase shifting method with a precise control of the effective range of phase shifting. For that purpose, newly developed configuration was implemented to the sensor for phase control to have it under permissible temperature range against resulting high installation temperature. Through those measures, it was achieved by using ferrite magnet to generate a compatible amount of electricity generation to that of using rare-earth metals without changing the dimensions of the generator.
Article of Honda R&D Technical Review Vol.27 No.1 (71 - 76)