The controller adopts a double closed loop control system (brushless: speed/current double closed loop, brush: voltage/current double closed loop). Due to the existence of the current loop, the current can be limited, which can protect the electric vehicle in various normal conditions. Under operating conditions, the maximum current output value will not exceed the set current limit value and realize automatic current limiting, so that under any operating conditions, the battery will not have a discharge process that exceeds the set value current, which ensures the safety of the battery. In addition, due to the cooperation of the double closed loop, the motor can achieve the most ideal starting process and acceleration process, so that the current of the battery can be effectively used, which can increase the mileage of the electric bicycle. Since the commercially available controller is a single closed-loop control system and relies on the current limiting function of the MC33035 (MC33033) chip, the controller often outputs a large current to the current limiting protection during startup and acceleration.