Permanent Magnet Motor Modeling
Software Evaluation
Kaila Krieser, EE
Dan Montgomery, EE
Craig Christofferson, EE
Mark Wisted, EE
Dr. Mani Mina, Advisor
Dave Sowders, Kansas City Plant Client
Project Objective

Client: The Electrical Engineer student will select, use and
assess an electromagnetic modeling software tool to
simulate Permanent Magnet Motor operation in variable
magnet and environmental configurations.

Revised: Design an evaluation package to select, use, and
assess electromagnetic modeling software tools for
permanent magnet motor simulations in variable magnet
and environmental configurations. The evaluation package
will be tested using four acquired software tools and a
universal PMM model, designed by the team.
Project Plan: System Block Diagram
Research
PMM Function
PMM Modeling Fundamentals
Magnetic Material Characteristics
Modeling Software Tools
Model Design
Machine parameter selection
Material selection
Machine rating assignment
Software Selection
Simulation and Testing
FEMM
ANSYS Electromagnetics
Cobham Opera-2D
Infolytica MagNet
Finite element mesh solution
Performance characteristic simulation
Accuracy verification
Infolytica MagNet
Software Evaluation
Overall Description
Modeling Performance Characteristics
Notable System Features
External Interfaces
Quality Attributes
Project Plan: Market Survey

The intended use of this evaluation is research in the
field of permanent magnetic motor modeling
software. Specifically, the software will be used to
model current and future PMM designs and
permanent magnet material enhancements for basis
of future purchase and/or production decisions.
Project Plan: Functional Requirements

Selection of Modeling Software Tools


Model Design


A general permanent magnet motor will be designed to work with
any modeling software and comply with client expectations.
Model Simulation


Based on availability and cost, four modeling software tools were
selected for the project.
The model will be simulated with each software to analyze specific
performance characteristics, such as flux linkage, back EMF, cogging
torque, etc.
Software Evaluation

Each software will be evaluated for effectiveness in making
implementation and purchase decisions in industry and research.
Project Plan: Deliverables




PMM Model Design
Software Evaluations
Final Report
Project closure conference call
Design Approach: Research


PMM Function
PMM Modeling Fundamentals







Finite Element Analysis
Polygonal Mesh Modeling
2D versus 3D Analysis
Static, Transient, and Time Harmonic
Performance Characteristics
Magnetic Material Characteristics
Magnet Materials
Design Approach: Modeling Software
Tool Selection




Finite Element Method Magnetics (FEMM)
Cobham Opera-2D
ANSYS Electromagnetic Solutions
Infolytica MagNet 2D Static
Design Approach: Model Design

Machine Parameter Selection


Permanent Magnet Definition



3 Phase 50 Hz AC, 4 pole, 24 slot motor
PM coercivity = -800 kA/m ~ 1T
μr = 1
Machine Rating Assignment


POutput = 0.35-0.375 kW
~ ½ hp
VRated = 415V
Design Approach: Simulation and
Testing



Possible simulation characteristics: flux linkage, cogging
torque, back EMF, output torque, and efficiency.
Measured and simulated characteristics: cogging torque
and back EMF.
Simulation method specific to each software, but generally
based on finite element analysis and 2D mesh.
Design Approach: Software Evaluation
Template
Section
Evaluation Criteria
Weight
2
Overall Description
20%
2.3
Operating Environment
20%
0
2.4
User Documentation, Customer Support
30%
0
2.5
Cost and Availability
50%
0
Subtotal
100%
0
Modeling Performance Characteristics
50%
3
3.1
Score
Weighted
Flux Linkage
3.1.2
Usability
6%
0
3.1.3
Simulation Results
6%
0
3.1.4
Accuracy
8%
0
3.2
Cogging Torque
3.2.2
Usability
6%
0
3.2.3
Simulation Results
6%
0
3.2.4
Accuracy
8%
0
3.3
Back Electromotive Force
3.3.2
Usability
6%
0
3.3.3
Simulation Results
6%
0
3.3.4
Accuracy
8%
0
3.4
Output Torque
3.4.2
Usability
6%
0
3.4.3
Simulation Results
6%
0
3.4.4
Accuracy
8%
0
3.5
Efficiency
3.5.2
Usability
6%
0
3.5.3
Simulation Results
6%
0
3.5.4
Accuracy
8%
0
Subtotal
100%
0
Notable System Features
20%
4.1
Material Flexibility
25%
0
4.2
Transient Analysis
25%
0
4.3
Notable System Features
50%
0
Subtotal
25%
0
External Interfaces
10%
5.1
User Interfaces
80%
0
5.2
Software Interfaces
20%
0
Subtotal
100%
4
5
Weight
Total
100%
0
Score
Weighted
0
Finite Element Method Magnetics (FEMM)

FEMM provides a simple and quick platform to run basic simulations
for model designs, but lacks advance simulations ability.
Cobham Opera-2D

Cobham Opera-2D a powerful, yet complicated modeling
software tool.
Infolytica MagNet

MagNet static 2D is a modeling software tool that is usable
and effective, but transient analysis was not available.
ANSYS Electromagnetic Solutions

ANSYS Electromagnetics is a modeling software tool with
transient analysis that enables a variety of measurements to be
analyzed from a single simulation.
Back EMF - Accuracy Comparison
Back EMF - FEMM
Back EMF - Opera-2D
150
150
150
100
100
50
0
0.000
-50
50
-100
0.005
0.010
0.020
0
0.000
0.005
0.010
0.015
0.020
-50
-150
ANSYS
-100
Time [s]
0
0.000
MagNet
-150
0.005
0.010
0.020Time [s]
0.015
FEMM
Opera-2D
Dr. Al-Naemi Measured
-100
-150
Back EMF - MagNet
Dr. Al-Naemi Simulated
Back EMF - ANSYS
150
150
100
100
50
50
0
0.000
-50
0.005
0.010
-100
-150
0.015
Time [s]
Time [s]
0.020
EMF [V]
-50
EMF [V]
EMF [V]
0.015
EMF [V]
EMF [V]
100
50
0
0.000
-50
0.005
0.010
-100
-150
Time [s]
0.015
0.020
ANSYS
Cogging Torque - FEMM
Cogging Torque - Opera-2D
Cogging Torque - Accuracy
0.150Comparison
0.150
0.100
0.100
0.050
0.050
0.100
0.000
0
0.001
0.002
0.003
0.004
0.005
0.006
Torque [N∙m]
Torque [N∙m]
0.150
0.007
-0.050
0.001
0.002
0.003
0.004
0.005
0.006
Time [s]
Time [s]
Opera-2D
MagNet
0.000
0
0.001
0.002
0.003
0.004
Cogging Torque - MagNet
0.100
0.100
0.050
-0.100
0.050
0.000
0.002
0.003
0.004
-0.050
-0.150
0.006
0.007
0.006
0.007
0.000
0.0000
0.0010
0.0020
0.0030
0.0040
-0.050
Time [s]
-0.100
-0.150
0.005
Torque [N∙m]
0.150
0.001
0.005
-0.100
Time [s]
FEMM
Cogging Torque - ANSYS
0.150
-0.050
0
0.007
-0.050
-0.150
-0.150
Torque [N∙m]
0
-0.100
0.050
-0.100
Torque [N∙m]
0.000
-0.150
Time [s]
0.0050
ANSYS
0.0060
0.0070
Summary/Recommendation

ANSYS EM is the best fit modeling software tool for the
scope of this project.
Software
Back EMF Accuracy Cogging Torque Accuracy Software Rating
ANSYS
6.40%
4.70%
0.782
MagNet
8.00%
3.00%
0.686
13.00%
0.90%
0.628
8.00%
19.5%
0.512
Opera-2D
FEMM
Project Milestones & Schedule
Problem Definition
Background Research
Planning and Design
Simulation and
Evaluation
End Documentation
End Demonstration
Project Reporting
8/30/10
10/30/10
12/30/10
3/1/11
5/1/11
Cost
Software:
FEMM
Cobham Opera-2D
ANSYS EM
Infolytica Magnet
Free online
Free 90 day trial
$2,000
$1,800
Reporting: Project Poster
Bound Project/Evaluations
Subtotal
Labor:
1196 hours * $20/hour
$34
$15
$3,849
$23,920
Total
$27,769
Questions?