국외학술지[2021.05]"Operating lines for plug-in hybrid turbo charger systems meeting LEV III evaporative gas regulations", Journal of Mechanical Science and Technology

◎ Title : Operating lines for plug-in hybrid turbo charger systems meeting LEV III evaporative gas regulations

◎ Authors : Young Kyu Oh, Sungwook Park

◎ Source : Journal of Mechanical Science and Technology  /  Vol. 35, Issue 8, Page: 3723-3734, DOI : 10.1007/s12206-021-0741-7 

◎ Published : AUG 2021

◎ Indexed : 2021-08-20

◎ Keywords : Turbo-GDI (gasoline direct injection) engine; EVAP LEVIII regulation; Operating line properties control; Dual purge system; Single purge system 


◎ Abstract :

 In 2020 the California Air Resources Board (CARB) implemented even more stringent regulation of vehicle emissions, its low-emission vehicle III (LEV III) program. In a (P)HEV T-GDI vehicle, the vehicle operates in EV driving mode when the engine is off, making it similarly difficult to comply with evaporative gas regulations. Automotive OEM strategy development to reduce vehicle evaporative gas and exhaust gas is in progress as these new emissions regulations are being implemented. Unlike in a naturally aspired engine, in a turbo gasoline direct injection (T-GDI) engine, the main operating area is the turbo boosting area. It operates in the positive pressure area rather than the negative pressure area, making it difficult to meet the requirements of the new evaporative gas regulationsI. The (P)HEV T-GDI characteristics showed the evaporative gas standards of LEV III, as well as regulations on CO2, fuel efficiency, and exhaust gas. 2.0 T-GDI single purge system vehicles showed 1.8 times engine operation time test results satisfied with evaporative gas test regulation values. Additionally, exhaust gas emissions in hot mode showed that CO(g/mile) affects 2.0 L T-GDI vehicles 2∼3 times more than 3.0 L V6 T-GDI dual purge system vehicles. Fuel efficiency test results, confirming that the 3.0 V6 had about 15 % FTP, 20 % HWY, 18 % US06 better fuel efficiency compared to the 2.0 L T-GDI vehicles. Furthermore, the properties of the operating lines optimized for two plug-in hybrid turbo charger systems to assess whether they can meet the evaporative gas standards of LEV III, as well as regulations on CO2, fuel efficiency, and exhaust gas. The 2.0 L T-GDI vehicle bears fuel economy loss, increases the engine operating time, and responds to the regulation of evaporative gas, and the 3.0 V6 confirms that the engine operating time, fuel economy, exhaust gas, and evaporative gas are optimized. To respond to LEV III evaporative gas regulations, 2.0 L T-GDI PHEV vehicles take longer engine operation time, fuel economy loss, and respond to evaporative gas, CO2, emission regulations, 3.0 L V6 T-GDI PHEV vehicles confirmed that engine operation time, fuel economy, exhaust gas, and evaporative gas were optimized. They can meet the evaporative gas standards of LEV III, as well as regulations on CO2, fuel efficiency, and exhaust gas.