Energy Recovery Electric Bicycle with Two-Quadrant DC Motor Drivers

This work implements the feasibility of an energy recovery electric bicycle with two-quadrant dc motor drivers to control the speed of ridden downhill. When the bicycle is pedaled, slowing down or coasting, the current flows in reverse to charge the battery, which thus enhances sustained ability and decreases energy consumption by the battery. Regarding the driving motors for electric bicycles, permanent magnet dc motors are chosen as the controlled objects in this study. The speed of permanent magnet dc motors is changed via the armature voltage control method by connecting a dc-to-dc driver between the voltage source and the motor. Regarding the drivers, pulse-width-modulation (PWM) is used to control the turn-on timing of semiconductor devices in the drivers. A wider pulse width implies a higher mean armature voltage and higher motor speed, and vice versa. Finally, simulation results using PSpice software demonstrate the theoretical effectiveness and the feasibility of the proposed apparatus.