OUTLINE Fundamental Power Requirements Single Regime IVT (Infinitely Variable Transmission) Perbury Multi-Regime IVT Engine Optimum Operating Line Typical Fuel Consumption Bath University/NREL Simulation Predictions for Perbury IVT Summary – How to increase MPG Conclusions
Engine Fuel Map and Vehicle Gearing 100 Maximum Torque 40 Max Power 80 240 34 250 g/kW.h 60 270 25 19 Mph/1000 rpm Torque – lb ft 300 90 40 400 80 600 20 MPH 60 800 1000 30 0 1 3 2 4 5 Engine RPM – 000s
Engine Fuel Map and Vehicle Gearing 100 Maximum Torque 40 80 90 Max Power 80 70 240 34 60 With efficiencies 250 g/kW.h 60 270 50 25 Optimum Line 19 Mph/1000 rpm Torque – lb ft 300 90 40 40 400 80 600 20 30 MPH 60 800 1000 30 0 1 3 2 4 5 Engine RPM – 000s
Introduction to ADVISOR ADVISOR, NREL’s ADvanced VehIcle SimulatOR, is a set of model, data, and script text files for use with Matlab and Simulink. It is designed for quick analysis of the performance and fuel economy of conventional, electric, and hybrid vehicles. ADVISOR also provides a backbone for the detailed simulation and analysis of user defined drivetrain components, a starting point of verified vehicle data and algorithms from which to take full advantage of the modeling flexibility of Simulink and analytic power of Matlab. ADVISOR was preliminarily written and used in November 1994. Since then, it has been modified as necessary to help manage the US DOE Hybrid Vehicle Propulsion System subcontracts. Only in January 1998 was a concerted development effort undertaken to clean up and document ADVISOR. Since then, researchers at Chrysler Corp. General Motors Corp. AlliedSignal Automotive Argonne National Laboratory Naval Research Laboratory University of California-Davis University of Maryland University of Illinois-Urbana/Champaign and other research institutions have used ADVISOR to predict the performance of their vehicles, do studies on the effect of control strategy on emissions and fuel use, among other things.
MPG vs Minimum Engine RPM 1500 1400 1300 1200 1100 Modified Min. Engine RPM Minimum Engine Speed - RPM 1000 SC03 FTP 900 US06 800 HWFET 60 100 110 120 70 80 90 130 UK MPG
Feasible Used in the simulation
How to increase miles per gallon Reduce engine speeds by high vehicle gearing Keep to a chosen engine optimum line but allow for transient departures After attaining maximum overdrive, bypass the rolling assembly For a given transmission, select the final drive ratio to suit the vehicle speeds during bypass ONLY AN IVT CAN DO ALL THIS AND STILL BE SMOOTHLY DRIVABLE
Conclusions Changing from fixed ratios to IV can indeed increase MPG Simulation increases are approximately 20% better than the Honda Insight Hybrid and 30% better than the 5-speed manual Even greater increases than this seem to be possible An additional benefit - cars and traffic can be quieter as well