Downward slope driving control for electric powered wheelchair based on capacitor regenerative brake

This paper describes a novel capacitor regenerative braking control scheme of electric powered wheelchairs for efficient driving on downward slopes. ¿Electric powered wheelchair¿ which generates the driving force by electric motors is expected to be widely used as a mobility support system for elderly people and disabled people, however, the energy efficiency has to be further improved because it is driven only by the battery energy. This study proposes a capacitor regenerative braking circuit and two types of velocity control schemes with variable duty ratio. The proposed regenerative braking circuit is based on the step up/down circuit with additional resistance and connects the right and left motors in series. Some driving experiments on the practical downward slopes show the effectiveness of the proposed control system.