PEMS를 이용한 소형 경유차의 실주행 NO x 배출특성 평가

NO x emissions from diesel vehicles have been regarded as a main cause of high NO₂ concentration in metropolitan area. Recent studies have shown that the on-road NO x emissions of diesel vehicles are quite higher than the emission limits specified with the pre-defined test method for emission certification. To reduce air pollutants effectively, the discrepancy of emissions in certification and real-driving conditions should be tackled. In this study, the real-driving emissions have been estimated with portable emission measurement system (PEMS). The results of this study have shown that the on-road NO x emissions from diesel vehicles have been decreased as the introduction of stricter emission regulation, EURO-6, but additional reduction should be still required and robust technologies should be applied to control NO x in real-driving conditions. RDE-LDV (Real Driving Emission - Light Duty Vehicles) test method being developed in the European Union can represent excessive on-road NO x emissions of diesel vehicles as applied emission technologies and can be a solution to remove discrepant NO x emissions between certification and Korean real-driving conditions. Among the NO x reduction technologies for EURO-6 diesel vehicles, selective catalytic reduction (SCR) system has shown the better performance than lean NO x trap (LNT) system to control on-road NO x emissions. Implementing RDE-LDV will require vehicle manufacturers to adopt the more effective NOx reduction technology in real driving conditions.