Browse Publications Technical Papers 2016-01-1141
2016-04-05

Modeling of a Conventional Mid-Size Car with CVT Using ALPHA and Comparable Powertrain Technologies 2016-01-1141

The Advanced Light-Duty Powertrain and Hybrid Analysis (ALPHA) tool was created by EPA to evaluate the Greenhouse Gas (GHG) emissions of Light-Duty (LD) vehicles [1]. ALPHA is a physics-based, forward-looking, full vehicle computer simulation capable of analyzing various vehicle types combined with different powertrain technologies. The software tool is a MATLAB/Simulink based desktop application. The ALPHA model has been updated from the previous version to include more realistic vehicle behavior and now includes internal auditing of all energy flows in the model [2]. As a result of the model refinements and in preparation for the mid-term evaluation (MTE) of the 2022-2025 LD GHG emissions standards, the model is being revalidated with newly acquired vehicle data.
In the effort to model the current and future US Light-Duty fleet there are times when complete and exact engine and powertrain component data are unavailable and must be approximated using components with comparable levels of performance and technology. This paper presents the testing and ALPHA modeling of a CVT-equipped 2013 Nissan Altima 2.5S using comparable powertrain technology inputs. A brief overview of recent improvements in CVT performance and efficiency is provided. ALPHA’s CVT shift strategy, ALPHAshift-CVT, is introduced and its performance is compared with data from the Altima. Fuel economy and carbon emissions results over a wide range of drive cycles were within 5% of measured values and the city/highway weighted combined fuel economy and carbon emissions were within approximately 1% of measured values, providing confidence in the proxy powertrain approach.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 18% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:
TECHNICAL PAPER

Modeling the Effects of Transmission Gear Count, Ratio Progression, and Final Drive Ratio on Fuel Economy and Performance Using ALPHA

2016-01-1143

View Details

JOURNAL ARTICLE

Investigating the Effect of Advanced Automatic Transmissions on Fuel Consumption Using Vehicle Testing and Modeling

2016-01-1142

View Details

TECHNICAL PAPER

Dynamic Programming-Based Design of Shift Scheduling Map Taking into Account Clutch Energy Losses During Shift Transients

2016-01-1116

View Details

X