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the architecture for simulation using automated model configuration tools. The system
model incorporates submodels for physical and control elements of the vehicle
system. As an example, for power split hybrid electric vehicle system simulation, the
set of submodels includes a power split transaxle subsystem model, a high voltage
(HV) electrical subsystem model including high voltage battery and a model of the
power split vehicle system controller. The system model represents the longitudinal
dynamics of the chassis and one-dimensional rotational dynamics of the powertrain
system. All mechanical and electrical component losses that have impact on energy
usage and fuel consumption are included and distributed across the relevant
subsystems. These losses are typically represented by component maps derived from
bench/lab tests or high fidelity physical models. Further discussion of the CVSP
simulation environment and how it is applied to electric vehicle system assessment
can be found in [4] and [3].
2.2 Traffic Simulation
Traffic micro-simulations are proposed as a way to produce realistic drive cycles.
These simulations have been developed for testing the performance of roadway de-
signs and signal light timing schedules, and generally for improving the performance
of transportation infrastructure. Typically they are used in the domain of the traffic
engineer and not traditionally used for vehicle simulation.
Traffic micro-simulations are time-event driven simulations that implement a driv-
er model for individual vehicles that are placed on a model roadway. They implement
psychophysical driver models that employ vehicle physics and a physiological model
of driver following behavior. A detailed discussion of driver models for micro-
simulation modeling is found in [6].
Roadways are modeled as directed graphs in micro-simulation and individual ve-
hicles placed on the model roadways have proven to be a reasonable way to model
traffic flows that consider jams, congestion and different driver behaviors. Other fac-
tors can also be considered such as weather and topography.
A primary advantage of micro-simulation over other methods of producing drive
cycles is that there is a straightforward analytical model that links physical features of
the road, traffic and human perception to the creation of synthetic drive cycles. Mod-
els are calibrated using in-vitro data such as that collected in driving simulators, es-
tablished psychological theory and observation traffic behavior from aircraft. Fre-
quently micro-simulation software is calibrated for good results for bulk traffic flows
consistent with those observed by traffic monitors or detection equipment placed in
the roadway.
There are a number of traffic micro-simulation packages readily available from
open-source, commercial and academic sources. In our study we used VISSIM [5]; a
mature, full featured traffic simulation package. VISSIM is a time driven microscopic
simulation package from PTV that can analyze private and public transport operations
under constraints such as lane configuration, traffic composition, traffic signals, pub-
lic transportation stops, etc., thus making it a useful tool for the evaluation of various
alternatives based on transportation engineering and planning measures of effective-
ness. VISSIM can be applied as a useful tool in a variety of transportation problem
settings. Simulated Vehicles are allowed to run through a road model, each
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