Open Access Thesis
Date of Award
The objective of the research into modeling and simulation was to provide an iterative improvement to the Wayne State EcoCAR 2 team's math-based design tools for use in evaluating different outcomes based on hybrid powertrain architecture tweaks, controls code development and testing. This thesis includes the results of the team's work in the EcoCAR 2 competition for university student teams to create and test a plug-in hybrid electric vehicle for reducing petroleum oil consumption, pollutant emissions, and Green House Gas (GHG) emissions.
Plant model validations and advancements brought the vehicle plant model directionally closer to the actual vehicle's experimental data and achieved a significant error reduction in 10 of 11 metrics detailed in the research. The EcoCAR 2 competition events provided the opportunity for the team to get experimental data of the vehicle's behavior on the vehicle chassis dyno and the vehicle on road testing from General Motors proving ground test tracks. Experimental data was used from 5 sources to validate and advance the vehicle plant model:
1. Component Test Benches
2. HIL Test Bench
3. Component on Dynamometer (Dyno)
4. Vehicle on Chassis Dyno
5. Vehicle On Road
The advancement of the electric motor powertrain and the vehicle chassis portions of the vehicle plant model provided significant error reduction (at least a 10% reduction) in:
* Dynamic Performance metrics (2 of 3 had more than 10% error reduction):
o 9% --> 0% 0-60 mph Acceleration
o 15% --> 19% 50-70 mph Acceleration
o 37% --> 3% Braking Distance, 60-0 mph deceleration
* Emissions & Energy Consumption metrics (8 of 8 had more than 10% error reduction):
Utility Factor (UF) is from SAE J1711 standard for measuring the exhaust emissions and fuel economy of HEV's and PHEV's
o 49% --> 16% Total Vehicle Range (ESS + Fuel Tank)
o 11% --> 0.2% Charge Depletion Range
o 43% --> 24% Charge Sustaining Fuel Consumption
o 47% --> 27% UF-Weighted Fuel Energy Consumption
o 9% --> 1% UF-Weighted AC Electric Energy consumption
o 38% --> 21% UF-Weighted Total Energy Consumption
o 45% --> 26% UF-Weighted Well To Wheel Petroleum Energy Use
o 43% --> 31% UF-Weighted Well To Wheel GHG Emissions
However, significant error (more than 10%) still exists and more work is needed in:
* 1 of 3 Dynamic Performance metrics
* 6 of 8 Emissions & Energy Consumption metrics
Future work includes adding a torque converter plant model between the engine plant model and the transmission plant model on the front wheel drive powertrain, implementing identified advancements into the engine and transmission plant models, and additional analysis for validation of the engine and transmission plant models.
The vehicle plant model now provides higher confidence and higher accuracy (in most cases) for the simulation results, making the vehicle plant model significantly more useful for evaluating fuel economy, dynamic performance, and emissions improvement results when testing the team's controls code changes for optimization.
Snyder, Kevin Lloyd, "Advancement And Validation Of A Plug-In Hybrid Electric Vehicle Model Utilizing Experimental Data From Vehicle Testing" (2015). Wayne State University Theses. 414.