Study On Fuel Economy And Emissions Of Vehicles With Start/Stop System

The impact of current vehicle start-stop technology on fuel consumption and emissions in Chinese road conditions,this article has passed a series of studies including actual road and laboratory tests.The fuel economy and emissions of vehicles equipped with start-stop systems were analyzed.This paper first expounds the background significance of the start-stop technology,the research status at home and abroad,and key technologies,analyzed the composition of the automatic start-stop technology,it mainly includes the driver’s parking intention judgment,engine stop control,driver’s start intention judgment and vehicle start running;Then,a detailed comparative analysis of the actual road conditions data at home and abroad is carried out,and the method of constructing domestic road conditions and testing methods of fuel consumption and emissions are determined;After collecting driving data of representative cities and sections in China,build a laboratory development condition that fits the actual road conditions in China at this stage,finally,the actual roads and laboratories were thoroughly tested on equipment and unequipped vehicles,the impact of vehicle start-stop system on fuel economy and pollutant emissions in China’s road conditions is obtained.In order to better meet the actual traffic situation in China,more accurately test the impact of the start-stop system on fuel economy and pollutant emissions,this project selects representative cities,time periods and road sections in China,the actual road experiment plan was designed,and a cycle of conditions that can represent the actual road conditions in China was constructed.In the actual test,seven different brands of light passenger vehicles were selected for experiments,and these vehicles were equipped with different start-stop systems（three system manufacturers）for more accurate testing of the start-stop system for pollutant emissions.The impact of quantity.Through the actual road test and the laboratory bench test,it is shown that the start-stop technology can greatly reduce the fuel consumption of the vehicle.The higher the idle speed ratio,the more obvious the fuel-saving effect;Under development conditions,reduce fuel consumption by 8.5 to 10.5%;In the actual road fuel consumption test,the ratio of idle speed is about 18 to 43%,and the fuel saving is about 7 to 19%.At the same time,four different types of test vehicles were selected for wheel test,and the impact of stop technology on emissions was studied.It has a significant effect in reducing CO₂.In NEDC-I,it reduces fuel and CO₂emissions by 5-10%.Under the circumstance,CO₂emissions are 8.5-10.5%;After the start-stop function is activated,the vehicle has obvious emission reduction effects in terms of NOx emissions under the NEDC-I operating conditions,but the NOx emissions change little under development conditions;The start-stop technology has less impact on the discharge of other pollutants.Based on the actual road test,this project has established a development condition cycle that is more representative of China’s actual road conditions,on this basis,through the actual vehicle and laboratory test,it is concluded that the vehicle with the start-stop system can effectively reduce the fuel consumption under the working conditions in China,and also help to reduce pollutant emissions.