Improved Vehicle Thermal Management Simulation with

Improved Vehicle Thermal
Management Simulation
with MotorSolve and
Flowmaster
Doug Kolak
Flowmaster Product Specialist
Mentor Graphics
Derek Dyck, Ph.D
Project Leader
Infolytica
Agenda

Introduction
— Hybrid-Electric Vehicle Thermal Management
— Why use MotorSolve?
— Why use Flowmaster?
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Model-Based Design MotorSolve to Flowmaster
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Case Study: Varying Motor Coolant Heat Exchanger
Location

Summary

Questions
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Future Production
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Production of Electric Cars is increasing:
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Mitsubishi i-MiEV
Nissan Leaf
Ford Focus EV
Coda Sedan
Tesla Model S
Toyota RAV4 EV
Honda Fit EV
Smart Fortwo ED EV
Chevy Spark
Renault Zoe
Nissan Leaf
KPMG predicts that
electric-car sales will reach
15% of annual global car
sales by 2025
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Challenges - Vehicle System Level Design
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Vehicle generic
— Coupling design constraints with operational conditions
— Efficient validation of the entire system design
— Evaluating system performance
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Hybrid/EV specific…less waste heat available!
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Battery Heating/Cooling
Charger & Inverter Cooling
Traditional Vehicle Thermal Management
New Cabin Considerations
Motor Cooling
Where to get
data?
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Why use MotorSolve?
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Easy to use template interface
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Import custom rotor, stator or
armature
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Automatically determines all
balanced winding configurations
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Highly accurate FEA-based results
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Ideal or Non-ideal Drives
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Thermal Module: losses/heating &
impact of cooling
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VHDL-AMS/Simulink export for
system simulation
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Supported Machine Types
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Brushless DC Motors
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Variable Frequency
Synchronous
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AC Synchronous
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Induction Machines
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Switched Reluctance
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DC Machines
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Why use Flowmaster?

An efficient means of derisking the Engineering
Process
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Used across virtually all
thermo-fluid applications
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Flowmaster’s key strengths
Libraries of components,
performance data, fluid
and material properties
Simulation
Configuration
Modern GUI
 In Built, Empirical Data
 Versatile, Transient Solver
 Extendable, Open Framework
 Fast Batch Simulations
 Secure, Traceable Data
Network modeling
Schematic Tool &
powerful post
processing
2D and 3D
Equation &
parametric inputs
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Automotive Applications
Engine Warm-up
Lubrication
Fuel Injection
Cabin
Battery Cooling
Engine Cooling
Airside
Fuel
Air-Conditioning
Exhaust
Steering / Brake Hydraulics
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Hybrid-Electric Vehicle Thermal Management
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Example 1D VTM Model
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Battery System [blue]
Power Electronics [red]
Lubrication [maroon]
ICE Cooling [green]
Cabin [yellow]
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Hybrid-Electric Vehicle Thermal Management
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How does the system affect
the cooling of the motor?
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How does cooling the
motor affect the system?
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Modeling a Liquid Cooled Motor Sub-system
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Separate sub-system interacting
via cooling pack air
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No standard electric motor
component
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Heat generation calculation
based on:
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Motor Speed
Motor Torque
Temperature Feedback
Efficiency Map, HTC, & Area
from MotorSolve
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Heat Loss Calculation: Speed and Torque
Rotational Speed
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Torque
MotorSolve Model: Prius 2010
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Excellent test data available
in the public domain
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Stator lamination found in
MotorSolve template library
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Optimized rotor geometry
imported as a dxf
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Thermal cooling “Spray
type” tuned to match ORNL
report results
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Cooling Setup in MotorSolve
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Thermal Results
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Thermal analysis allowed
the use of symmetry
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Large thermal time
constants allowed 30
second thermal time step
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Determined several
parameters for the
system model
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Short analysis time of ~4
minutes
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Efficiency Maps
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MotorSolve automatically
generated the efficiency
maps
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Calculations include all the
losses in the machine
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Friction
Windage
Joule Heating
Eddy Current
Iron and Stray
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Required 2016 finite element
2D field solutions
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Analysis time of ~40 minutes
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Heat Loss Calculation: Efficiency
Heat Flow Rate
T = 35C
T = 87C
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Temperature
Feedback
Heat Loss Calculation: Heat Transfer

Motor mass specified as an
equivalent mass of steel
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Heat Transfer Coefficient and
Area from MotorSolve
Motor Mass
Heat Transfer
Coefficient & Area
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CASE STUDY
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HEV Thermal Management – Configuration 1
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Liquid Cooled Motor
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Battery System [blue]
Power Electronics [red]
Motor [purple]
Lubrication [maroon]
ICE Cooling [green]
Cabin [yellow]
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HEV Thermal Management – Configuration 2
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Combined Motor and Power
Electronics
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Parallel to HEV Battery Heat
Exchanger
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HEV Thermal Management – Configuration 3
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First Heat Exchanger in
Cooling Pack
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Results in ~4 Minutes
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Motor Temperature Results
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Power Electronics Temperature Results
Increase Coolant Flow Rate?
Resize the Heat Exchanger?
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Radiator Inlet Air Temperature Results
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Thermostat Inlet Temperature Results
Is the Engine Efficient?
Change Fan Behavior?
Change Thermostat Behavior?
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Summary

Cooling of the motor can be greatly affected
by the system
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Heat exchanger position changes temperature
Coolant and air flow rate affects heat dissipation
Can act as a heat sink - BAD
Lower motor efficiency
Cooling of the motor can greatly affect the
system
— Heat added to the system
— Can act as a heat sink – Maybe GOOD
— Additional electrical/mechanical requirements
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© Mentor Graphics Corp. Company Confidential
www.mentor.com