Research on the Correlation Between Test Cycles and RDE Test

Abstract

WLTC cycle, CLTC cycle and RDE tests are carried on 3 vehicles with different technical types – PFI natural aspirated vehicle, DI natural aspirated vehicle and DI charged vehicle, the relationship between test cycles and real driving tests of 3 different vehicle types are studied. It is found that neither test cycles can completely cover the speed-acceleration range contained in the RDE tests, but the CLTC cycle covers a wider speed-acceleration range comparing to the WLTC cycle, which can cover more range of kinematic characteristics in the real driving process of each vehicle type. For 1.6 L PFI natural aspirated vehicle and 2.5 L DI natural aspirated vehicle, CLTC cycle shows a more similar overall acceleration distribution with the RDE comparing to WLTC cycle, but for 2.0 L DI charged vehicle, it is hard to tell which cycle is more close to RDE on the overall acceleration distribution. In general, for the wider coverage on the speed-acceleration range and more closer to the RDE test on the acceleration distribution ratio, the CLTC cycle can reduce the difference between the laboratory test cycles and the actual kinematic characteristics of real-world based RDE tests to a certain extent.