US EPA NVFEL Repeatable-Vehicle Program – Emission Lab Testing System Performance Quality Monitoring
2022-01-0689
03/29/2022
- Event
- Content
- According to US FCR the vehicle emission testing system must be monitored and checked periodically, and NVFEL TATD has developed a quality control monitoring program named “Repeatable-Vehicle Program”, the current vehicle selected is a proper sized and featured sedan, so called RepCar. The vehicle emission lab cell test used a chassis dyno to simulate some road driving conditions, a CVS system to collect exhaust sample and analyzed by a group of chemical benches. The testing condition is satisfied the FCR requirement and controlled during the testing procedure. A specific driving cycle including two phases was designed to evaluate vehicle power system at different speed load performance and measurement instruments accuracy under different concentration range. The phase1 is modified FTP505, phase2 is the most aggressive part of US06, and at the end of phase2 driving trace had a 30-second constant 75 mph cruising followed by a coast down. The RepCar equipped a data logger recording few OBD II parameters, which provided an independent information to crosscheck TWC control, CO2 or fuel consumption, vehicle physical condition, and driver’s behavior. Each Monday morning, all test cells will run the RepCar cycle by this RepCar. The test results include two bag data analysis, if needed a raw or diluted continuous bench analysis also compared and reported. When the RepCar database is established, every test cell performance has its own statistical measures, once anything went wrong or off, it can be monitored. Same time the whole lab test accuracy and consistency are observed and indicated the improvement direction. Along with dyno cell weekly routine TGI and SAC test, the RepCar test program helps the lab test quality keeping competitive for more and more stringent emission regulations.
- Citation
- Tang, X., "US EPA NVFEL Repeatable-Vehicle Program – Emission Lab Testing System Performance Quality Monitoring," SAE Technical Paper 2022-01-0689, 2022, .