Garrett to Participate in “CO2 Reduction for Transportation Systems” Conference

From 48V to High Voltage Dedicated Hybrid Powertrains: Numerical Assessment of Electrified Gasoline Architectures for a Low Emission C-SUV

Author: Garrett’s contribution to this paper through Philippe De Araujo, Sujeet Vankayala and Adam Vondrak

European institutions recently put forth a series of legislative proposals that target a 55% net reduction in passenger car greenhouse gas emissions by 2030, thus spurring the development of increasingly efficient electrified powertrains.

In this work, CAE simulation is employed to assess the impact of four different hybrid electric architectures on CO2 and pollutant emissions, applied to a gasoline-powered passenger car. As a first step, a model representing a conventional C-SUV segment vehicle endowed with a 1.5L turbocharged gasoline engine, was built in the multi-physics simulation software GT-SUITE. Then, four alternative variants of the original model were prepared: a 48V P0 Mild-Hybrid Electric Vehicle (MHEV), a 48V P2 MHEV, a 220 V Dedicated Hybrid Powertrain (DHP) and a 400 V DHP Plug-in Electric Hybrid Vehicle (PHEV). The latter two variants being equipped with a Dedicated Hybrid Engine (DHE) featuring increased Compression Ratio (CR) and Low-Pressure Exhaust Gas Recirculation (LP-EGR). An auto-adaptive Energy Management System (EMS) based on the Equivalent Consumption Minimization Strategy (ECMS) was integrated in the model, including Torque Assist and Sailing functionalities.

Eventually, the conventional vehicle and the four hybrid concepts were simulated over the WLTC in charge-sustaining mode, and their results compared. The P0 MHEV led to a 5.6% reduction in CO2, while the P2 MHEV attained a 7.9% decrease. The 220 V DHP configuration brought a 18% improvement in fuel consumption while the 400 V DHP plug in, in charge sustaining mode, achieved a 12% reduction in CO2. Adopting the homologation test for Off-Charge Vehicles (OCV), the PHEV attained a sizable 80% CO2 emission reduction and an electric range of 56 km.

Publisher: CO2 Reduction for Transportation Systems Conference (with the patronage of / in co-operation of SAE) on June 21-22, 2022