Based On The Single Motor Electric Car Energy Feedback Control Strategy Study

At present, the main barrier to electric vehicles is the driving range and cost, and the key factor causing these problems is energy system. Before making breakthroughs in the energy technology, it has become a very important subject in current study, how to maximize use of limited on-board energy and develop the efficient energy management system to prolong the driving range.Through studying theory knowledge of the BLDCM (Brushless DC Motor) in electric vehicles, testing the waveform under motor running and generator running, aiming at the characteristics of energy regenerative braking, combining with the practical road conditions, this article proposes an energy feedback control strategy and conducts the simulation research.This article just begins to study on the premise of constant speed from the perspective of energy. In the whole control strategy, it considers energy efficiency from the two-stage, saving energy and energy feedback.In the saving energy control strategy, when BLDCM is in the motor running state, not considering too much other factors, it considers and implements only from speed control, or using the motor speed closed loop control. By way of PWM modulation, it limits or reduces the output of electric power to reduce the frequency of using brake pedal as much as possible. In terms of the output of electrical power, it achieves the purpose of saving energy and makes electric vehicle running at a constant speed.In the energy feedback control strategy, while BLDCM is in the generator running state, making speed as the determinant of measuring current feedback, it control the entire system using the double closed loop control of the motor speed and the current. It not only resolves the difficulty that parameters of energy feedback curve can't be ascertained based on energy feedback curve control, but also can adjust the size of the current feedback in real-time traffic. Through the PWM modulation methods, the size of the feedback current is adjusted.In Simulink, combining with the mathematical model of the BLDCM and the energy feedback control strategy, it builds the simulation model of the whole control system and makes related simulation analysis.