Automatic Torque Control for Bicycle Driven Brushless DC (BLDC) Generator

Abstract: This work was carried out on behalf of Science Safari. Science Safari wants to create a product that facilitates the understanding of how much physical work is required to create electrical energy. This is done by cranking the pedals of a bicycle. The purpose of this work is to create a control unit that keeps the torque required to crank the pedals close to constant. The torque can be kept constant by creating a variable load for the generator, in this case, a pulse modulated JFET is used. The output of the current sensor and the Hall-effect sensor are used to calculate the required resistance of the JFET to keep constant torque. All this is controlled via a Raspberry Pi 3 Model B (RPi) which also shows real-time values on a display. The functionality of the sensors and JFET has largely been completed, but the assembly of all components is lacking in this work.