VSP-Bin division for light-duty vehicles oriented to carbon dioxide
针对二氧化碳的轻型汽油车VSP区间划分

Emission data collected from sixteen light duty vehicles in Beijing using a Portable Emission Measurement System (PEMS) were used to analyze the characteristics of impacts of Vehicle Specific Power (VSP) on CO2 emissions. Then, the VSP bins were re-divided based on the emission characteristics of CO2 with a consideration of both emission rates and emission contributions. The minimum value of the emission rate in the new VSP bins was 0.5587 g.s-1, and the maximum value was 3.4013 g.s-1; while the minimum value of the emission contribution in the new VSP bins was 4.61%, and the maximum value was 14.17%. The emission rate when VSP=0 was 0.5587 g.s-1, lower than those of neighboring bins, while the emission contribution was 14.17%, similar to those of other bins. Thus, VSP=0 was made an independent bin. Speed and Engine Stress (ES) were used separately to further divide the VSP-bins into 30 bins. Finally, the prediction of CO2 using the proposed VSP bins was validated in a case study for different classes of roads in Beijing. For expressways and non-expressways, the errors generated were 11.43% and 14.34% by MOVES, 12.23% and 15.53 by IVE, 10.05% and 12.57% by the proposed VSP-Bins, 9.10% and 11.56% by the proposed VSP-Speed-Bins, and 9.90% and 12.23% by the proposed VSP-Engine Stress-Bins. It is shown that the combination of VSP and speed generated the least errors in analyzing the CO2 emissions of on-road vehicles.