Heavy-duty hybrid vehicle emission contrast research under different modes

Two different types of heavy-duty hybrid vehicles had been tested by portable emission measure system (PEMS). Analyzed the two hybrid vehiclespsila emission characteristics under different modes by cycle classification method and provided technical support to hybrid vehiclepsilas control strategy. The results showed that the two hybrid vehiclespsila tracking correlation coefficient (R
²
) were both more than 0.99. Series vehiclepsilas HC, CO and PM emissions factor were lower than parallel, but NO
_x
and CO
₂
emissions factor were opposite. Series vehicle has the least exhaust emission mass under acceleration mode.