Optimisation of driving-parameters and emissions of a diesel-vehicle using principal component analysis (PCA)

Light-duty diesel vehicles contribute significantly to urban air pollution. Laboratory-based standard driving test cycles do not take into account external driving factors, which greatly impact the vehicle emissions compared to the real-world driving emission (RDE) measurements. This results in higher emission levels obtained by RDE tests, compared to the standard approaches. In the current study, an RDE measurement campaign has been conducted in Brisbane city traffic using a portable emission measurement system (PEMS). Thirty drivers with a wide variety of driving experiences participated using a Hyundai iLoad van in a custom test route. RDEs and driving parameters were recorded during each trip. Principal component analysis (PCA) was applied to investigate the relationship between driving dynamics and vehicle emissions. Also, the impact of different trips, driving time, and driving experience on driving behaviour and emissions. Route familiarity, traffic density, and driving experience have a strong impact on driving behaviour and emissions. The driver's response to changing traffic, unknown routes, and vehicles significantly vary among different drivers which results in a high volume of transient events (frequent acceleration and deceleration). Transient events are very common in city driving which has a strong correlation to vehicle emissions.