纯电动客车再生制动控制策略研究及系统实现

发布时间：2018-04-02 23:16

本文选题：纯电动客车　切入点：再生制动　出处：《吉林大学》2016年硕士论文

【摘要】：再生制动系统是纯电动客车的重要组成部分,对原车加装再生制动控制系统能够降低整车能耗、提高续驶里程并能够延长机械制动系统的使用寿命。加装再生制动控制系统在结构上只需在制动踏板上加装角位移传感器,而不需改动电机和动力电池结构,易于实现。再生制动控制程序也是整车控制策略的重要组成部分。提高制动能量回收利用率和降低制动模式切换时的冲击度是制定再生制动控制策略的两个重要的目的。本课题来源于吉林大学与吉林省高新电动汽车有限公司的合同“纯电动客车整车控制策略及控制系统开发”。本文需制定合理的再生制动控制策略,以提高纯电动客车续驶里程,并能保证再生制动模式切换时电机转矩变化平稳,使整车具有较好的乘坐舒适性。对再生制动控制系统进行设计,并进行硬件在环试验以保证控制系统的有效性,本文主要内容包括:(1)对再生制动主要部件进行机理分析。分析了气压制动控制阀结构及工作过程,在原车制动踏板上加装角位移传感器,通过试验对制动踏板开度与传感器采集电压值关系进行标定;分析了永磁同步电机制动原理,确定了电机及其冷却系统的布置方案,通过试验获得了电机外特性曲线;分析了动力电池特性,通过试验获得了充电时单体电池端电压与电池SOC的关系,并确定了电池充电电流门限值。(2)制定了再生制动控制策略。确定ECE法规和电机以及电池特性限制下的最大电机制动转矩;根据再生制动转矩限值曲线将制动模式划分为小、中、大三种;通过车辆加速度和电机驱动转矩对车辆载荷状态进行识别,在不同载荷状态时对制动模式划分的制动踏板开度值进行调整;制定了再生制动模式切换时的电机转矩控制策略。(3)在CRUISE仿真软件中搭建了整车动力学模型,并对仿真工况进行定义;在MATLAB/SIMULINK中搭建再生制动控制策略模型,包括车辆载荷识别模块、再生制动转矩控制模块以及再生制动模式切换控制模块,并进行联合仿真。仿真结果表明本文的再生制动控制策略提高了整车经济性,载荷识别控制能提高制动能量回收利用率,制动模式切换控制能提高切换时的舒适性。(4)对整车控制系统进行了设计。对整车控制器进行硬件及接口定义;制定了整车控制器与电池管理系统和电机控制器的CAN通讯协议;在codewarrior中编写了整车上下电控制以及再生制动控制等程序。搭建控制系统测试平台,对所制定的控制策略及控制系统进行硬件在环试验,结果表明本文的再生制动控制策略提高了整车经济性,载荷识别控制能提高制动能量回收利用率,制动模式切换控制能提高切换时的舒适性。
[Abstract]:Regenerative braking system is an important part of pure electric bus. Adding regenerative braking control system to the original vehicle can reduce the energy consumption of the whole vehicle, increase the driving range and prolong the service life of the mechanical braking system.In addition, the regenerative brake control system only need to install angle displacement sensor on the brake pedal in structure, without changing the structure of motor and power battery, so it is easy to be realized.Regenerative braking control program is also an important part of vehicle control strategy.Two important purposes of developing regenerative braking control strategy are to improve the utilization rate of braking energy recovery and reduce the impact degree of braking mode switching.This subject comes from the contract between Jilin University and Jilin High-Tech Electric vehicle Co., Ltd., "Development of Control Strategy and Control system for Pure Electric bus".In this paper, reasonable regenerative braking control strategy should be worked out in order to improve the driving mileage of pure electric passenger cars, and to ensure the smooth change of motor torque when the regenerative braking mode is switched, so as to make the whole vehicle have better ride comfort.The regenerative braking control system is designed, and the hardware in loop test is carried out to ensure the effectiveness of the control system. The main content of this paper includes the analysis of the mechanism of the main parts of regenerative braking.The structure and working process of pneumatic brake control valve are analyzed, the angle displacement sensor is installed on the brake pedal of the original vehicle, the relation between brake pedal opening and sensor acquisition voltage is calibrated through experiments, and the braking principle of permanent magnet synchronous motor is analyzed.The layout scheme of the motor and its cooling system is determined, the external characteristic curve of the motor is obtained by experiments, the characteristics of the power battery are analyzed, and the relationship between the terminal voltage of the single cell and the SOC of the battery during charging is obtained.The battery charging current threshold value is determined. 2) Regenerative braking control strategy is established.Determine the maximum motor braking torque under the limitation of ECE regulations and motor and battery characteristics, divide braking mode into three types according to regenerative brake torque limit curve: small, medium and large.The vehicle load state is identified by vehicle acceleration and motor driving torque, and the brake pedal opening value is adjusted in different load states.The motor torque control strategy of regenerative braking mode switching is established. The dynamic model of the whole vehicle is built in the CRUISE simulation software, and the simulation condition is defined, and the regenerative braking control strategy model is built in MATLAB/SIMULINK.It includes vehicle load identification module, regenerative braking torque control module and regenerative braking mode switching control module.The simulation results show that the regenerative braking control strategy in this paper can improve the economy of the whole vehicle, the load identification control can improve the recovery efficiency of braking energy, and the braking mode switching control can improve the comfort of the switch.The hardware and interface of the whole vehicle controller are defined, the CAN communication protocol between the whole vehicle controller and the battery management system and the motor controller is established, and the whole vehicle up and down power control and regenerative braking control programs are written in codewarrior.The test platform of the control system is set up and the hardware of the control system is tested. The results show that the regenerative braking control strategy in this paper can improve the economy of the whole vehicle and the load identification control can improve the recovery efficiency of braking energy.Braking mode switching control can improve the comfort of switching.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U469.72

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