Design of an auto-braking regulator for a small wind generator

Abstract

Wind generators require braking mechanisms to prevent serious damage in high wind speeds. This paper proposes an, automated, electronic solution to existing mechanical methods that are expensive and reduce reliability. The "soft" automatic braking system brakes the generator, by slowly decreasing the phase to phase resistance of the generator, allowing the generator to decelerate steadily until it is fully braked. Regulation is achieved by monitoring the charging voltage of the battery, braking the system when the battery is fully charged and releasing it when below fully charged. Synchronous rectification is also incorporated and results in an increase of output power from the system, by approximately 10%. High wind speed can also be sensed by monitoring the charging current or the current through the MOSFETs and the generator can be braked if necessary.