基于分段PWM占空比输出的电动汽车电动机控制系统设计

Design of electric vehicle motor control system based on Piecewise PWM duty cycle output

摘要:

为加快电动汽车在负载量变化时所表现出来的电量响应速率，从而降低执行电动机控制指令所需的电能消耗量，设计基于分段PWM占空比输出的电动汽车电动机控制系统。根据带存贮电容功率变换器的连接状态，调试功率变换器驱动电路、档位与油门给定输入电路的响应形式，联合DSP控制板与软启动模块，确保滑模转矩控制器不出现过量负载的情况，从而将电动汽车电动机控制系统的核心设备元件组合起来，完成硬件应用环境的搭建。在此基础上，研究PWM 占空比控制原理，利用开关磁阻电机数学模型，确定脉冲行为成因，并将整个脉冲行为区间规划成多个分段结构，完成基于分段PWM占空比输出电动机控制行为分析，结合各级应用设备，实现电动汽车电动机控制系统的设计。实验结果显示，在分段PWM占空比输出原理的作用下，无论负载量增大或减小，电动汽车所表现出来的电量响应速率均能保持相对较高的数值水平，能够将电动机控制指令执行所需的电能消耗量保持在理想数值区间之内，符合实际应用需求。

Abstract:

In order to speed up the electric response rate of electric vehicle when the load changes, so as to reduce the electric energy consumption required to execute the motor control command, an electric vehicle motor control system based on the output of piecewise PWM duty ratio was designed. According to the storage capacitor power converter connection status, debugging power converter drive circuit, gear and throttle response forms of a given input circuit, joint DSP control board and soft start module, ensure that synovial excess load torque controller does not happen, which will be the core of the electric motor control system equipment components together, complete the hardware construction of the application environment. On this basis, the principle of PWM duty ratio control, using the mathematical model of switched reluctance motor to determine the pulse behavior causes, and the whole pulse interval planning into multiple block structure, complete output motor based on PWM duty ratio control behavior analysis, combined with various applications, design of the control system of the electric car motor. Experimental results showed that the segmented PWM duty cycle and output principle, under the action of load increases or decreases, and electric vehicle power they can maintain the response rate of relatively high value level, can the electricity consumption for motor control instruction execution keep in ideal numerical range, can meet the demand of practical application.