A Methodology for the Experimental Validation at the Engine Test Bed of Fuel Consumption and NOx Emissions Reduction in a HEV 2022-24-0006

Due to the greater need to reduce exhaust emissions of harmful gases (GHG, NOx, PM, etc.), to promote the decarbonisation process and to overcome the drawbacks of electric vehicles (low range, high cost, impact of electricity production on CO2 emissions…), the hybrid-electric vehicles are still considered as the more feasible path through sustainable mobility. However, one of the main tasks to be accomplished to get maximum benefit from hybrid-electric powertrain is the management of the energy flows between the different power sources, namely internal combustion engine, electric machine(s) and battery pack.

In this paper a methodology for the experimental testing of HEVs energy management strategies at the engine test bed is presented. The experimental set-up consists in an eddy-current dyno and a light-duty common-rail Diesel engine. The methodology allows reproducing the reference driving mission by feeding the test bed automation system with engine speed and load profiles, identified by means of a vehicle dynamic model. The experimental tests are useful to assess the effective improvement achievable with a hybrid-electric powertrain compared to a conventional one, in terms of fuel-saving and emissions reduction. Particularly, in the present work the experimental analysis is carried out to validate the rule-based energy management strategy designed for a parallel P3 hybrid powertrain with Diesel engine for passenger car application. The experimental results, collected vs. a reference driving cycle derived from WLTC, exhibit a significant reduction of NOx emissions and fuel consumption for the hybrid-electric powertrain vs. the conventional one, confirming the results previously achieved in simulation environment.