Abstract:

To study the impact of different driving cycles on thermal aging of vehicles' three way catalytic converter （TWC）， a gasoline vehicle and a hybrid vehicle with the same engine which meet China VI emission standard are selected to carry out approved mileage accumulation （AMA）， standard road cycle （SRC）， world-wide harmonized light duty driving test cycle （WLTC） and real driving emission test （RDE）. Meanwhile， the operating parameters and TWC bed temperature are collected by established data collection system. Based on Arrhenius mechanism， the thermal aging intensity after durability tests with different aging cycles of 160，000 km is quantified as thermal damage， and the equivalent real driving mileage in different aging cycles are converted with the RDE cycle as the reference. The results show that， the 160，000 km thermal aging intensity of hybrid vehicle's TWC is lower than that of gasoline vehicle's TWC under the same aging cycle. The thermal aging intensity caused by AMA and SRC cycles is significantly higher than that caused by WLTC and RDE cycles under the same driving mileage. The thermal aging effect on TWC of 160，000 kilometers on AMA cycle and SRC cycle of pure gasoline vehicle is equivalent to that of 518，400 and 603，000 kilometers on real road respectively； and the thermal aging effect on TWC of 160，000 kilometers on AMA cycle and SRC cycle of hybrid electric vehicle is equivalent to that of 304，400 and 292，100 kilometers on real road， respectively.

Key words: three?way catalyst, AMA, SRC, RDE, thermal aging