BSG怠速起停系统车辆控制策略研究

Control Strategy of BSG Vehicle Idling Start-stop System

对怠速起停系统节油原理及影响因素进行分析。根据驾驶员安全性、驾驶习惯和舒适性及油耗排放性能,制定BSG起停系统发动机自动停机控制策略、发动机自动起动控制策略、关闭起停系统控制策略及起停协调控制策略,并设定各控制参数阈值。应用该策略搭载实车进行试验,结果表明起停控制策略可按驾驶员要求控制车辆起停。BSG系统NEDC综合工况节油4%~5%,城市工况节油12%,实际城市使用工况节油8.1%。BSG起停系统车辆排放满足国V要求,CO和THC污染物排放量明显降低,但NOx排放量略有升高。

The belt driven starter generator（ BSG） system structure,working principle and working mode were introduced,the oil-saving principle of start-stop system,the relationship between idle speed and oilsaving rate,and the relationship between idle time ratio and oil-saving rate were analyzed. According to the driver＇s safety,driving habits and comfort,fuel economy and emission,the BSG start-stop system control strategy was formulated,which included engine automatic stopping strategy,engine automatic starting strategy,start-stop system shutdown strategy,and start-stop coordination strategy. The start-stop control parameters threshold values of battery SOC,catalyst temperature,engine water temperature,environmental temperature,and braking system vacuum pressure were set. The strategies were applied to the real vehicle. On the revolving drum,the fuel consumption and emissions were tested in NEDC cycle with the carbon balance method and instantaneous fuel consumption equipment. On the road,the fuel consumption was tested in NEDC cycle and actual road conditions. The test results showed that the proposed control strategy was correct,the threshold value of control parameters was reasonable,and the control strategy satisfied the requirement of idle start-stop function. The revolving drum test results showed that the BSG system could save oil by 4% ~ 5% in NEDC cycle,and it could save oil by more than 12% in city conditions. The BSG vehicle emission met the national V emission standard. The CO and THC pollutants were decreased significantly,and the NOxpollutants were increased slightly. The road fuel consumption test results showed that during the morning rush of the city,the BSG system could save oil by more than 8. 1%.