© 2011 Maplesoft, a division of Waterloo Maple Inc.

Modeling and Simulation ofHEV and EV Power Electronics

Paul Goossens Vice President, Applications Engineering

Dr. Sam DaoApplications Engineer

© 2011 Maplesoft, a division of Waterloo Maple Inc.

The HEV/EV Modeling Problem

HEV and EV modeling presents new problems• Complex, multi-domain models

• Difficult to run in realtime for HiL applications

• Coupling between domains can cause unexpected responses

• Batteries and power electronics are very complex

• Costly prototypes must be built to reveal system-level problems

© 2011 Maplesoft, a division of Waterloo Maple Inc.

The Need for Fast and Accurate Models

Accurate system-level models require accurate battery and power electronics models• Electro-chemical battery models are very complicated physical systems with

complicated mathematical descriptions

• Interaction of battery with power electronics and vehicle dynamics reveals higher-order effects can be mitigated

• Access to system-level equations provides further insight

HEV Components

HEV Powertrain IC Engine

Simple: controlled torque driver (ideal or lookup map) Mean Value: physical equations for overall power output and fuel consumption Cycle-by-cycle: detailed four-stroke model

Engine/transmission coupling Controllable Friction Clutch (built into MapleSim library) Torque Converter (lookup tables for torque ratio and load capacity)

Transmissions Basic components

Decomposed planetary (planet-planet, planet-ring) Dual ratio planetary: co-rotating/counter-rotating planets

Manual 5-speed Automatic 4-Speed (ZF 4HP22: 3 planetary gears, 12 clutches) 6-speed Dual-clutch Ravigneaux 4-speed Lepelletier 4-Speed CR-CR 4-speed Continuously Variable Transmission (CVT) Ideal or Lossy (Lookup tables for meshing friction, torque friction, slip)

Differentials Passive/Active Ideal/Lossy

Energy Storage/Conversion

•Batteries/Fuel Cells•Motors•Generation/Regeneration•Power Conversion•State-of-charge control

Vehicle Dynamics

•Multibody components for 3D Chassis Modeling• Chassis/Suspension/Steering• Stability Analysis and Control

Example: Hybrid-Electric Vehicle

FTP Drive Cycle: Simulation Results

Power Split: Torque/Speed

© 2011 Maplesoft, a division of Waterloo Maple Inc.

Video

Sam Dao, PhD, Maplesoft

Battery Modeling in MapleSim

Batteries

Details Physics and Equivalent Circuit:

• Lead-Acid

• Ni-MH

• Li-Ion for the following chemistries:

LiNiO2, LiCoO2, LiV2O5, LiFePO4 (Lithium-iron/iron phosphate), LiMn2O4, LiMn2O4 low plateau, LiTiS2, LiWO3, NaCoO2.

© 2011 Maplesoft, a division of Waterloo Maple Inc.

Approaches to Battery Modeling

Circuit-based models:

• represents battery behaviour as electrical circuit

• conceptually simple

• hides the battery physics

Chemistry-based models

• more accurate modeling of all battery characteristics

• many configuration parameters

• complicated model

© 2011 Maplesoft, a division of Waterloo Maple Inc.

Circuitry Battery Model

© 2011 Maplesoft, a division of Waterloo Maple Inc.

Pros: Simple and easy to

understand Accurate model and fast

to simulate

Cons: Does not include

temperature effects New model has to be

developed when battery parameters are changed

Battery capacity

Short and long time response, charge depletion and recovery

Open-circuit voltage

Relate SOC to component values based on experimental data

Circuitry Battery Model

© 2011 Maplesoft, a division of Waterloo Maple Inc.

• Comparison with actual battery discharge:

Physics-Based Battery Models

© 2011 Maplesoft, a division of Waterloo Maple Inc.

• Lithium-Ion battery modeling using porous electrode theory: Cathode: Anode:

6 6yLi C C yLi ye 1 2 2yLi CoO yLi ye LiCoO

Porous negative electrode contains graphite

Porous separator

Porous positive electrode contains metal oxides

Physics-Based Battery Models

© 2011 Maplesoft, a division of Waterloo Maple Inc.

Distribution of liquid-phase concentration over x:

Physics-Based Battery Models

© 2011 Maplesoft, a division of Waterloo Maple Inc.

Discharge voltage with pulse current (30 A) Battery voltage with different cathode chemistries

Paul Goossens, Maplesoft

Power Electrical Components

and Circuits in MapleSim

Basic Components

Semiconductors BJT (NPN, PNP) MOSFET (N, P) Diodes

Triggered components Thyristor, GTO

Multi-phase components

Motors/Generators

DC Permanent Magnet, Excited Armatures Equivalent Circuit

AC Synchronous and Asynchronous Multi-phase

Stepper

Brushless DC

Power electrical subsystems

IGBT

© 2011 Maplesoft, a division of Waterloo Maple Inc.

IGBT Single-stage Driver

© 2011 Maplesoft, a division of Waterloo Maple Inc.

Three-phase IGBT Drive

© 2011 Maplesoft, a division of Waterloo Maple Inc.

Asynchronous Induction Motor Speed

© 2011 Maplesoft, a division of Waterloo Maple Inc.

What is MapleSim?

MapleSim is a truly unique physical modeling tool:

• Built on a foundation of symbolic computation technology

• Handles all of the complex mathematics involved in the development of engineering models

• Multi-domain systems, plant modeling, control design

• Leverages the power of Maple to take advantage of extensive analytical tools

• Reduces model development time from months to days while producing high-fidelity, high-performance models

Summary

Complex physical modeling is becoming increasingly important – and increasingly complex – particularly in EV and HEV systems design, testing and integration

MapleSim is the ideal tool for rapid development of complex multi-domain physical models of EV and HEV systems for full-powertrain simulation and testing

Extensive range of battery and power-electronic models is available to give you the fidelity you need

Thank You

Questions?

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