ANSYS Emag Capabilities

1. ANSYS Emag 8.0 Capabilities Overview
Dr. Paul Lethbridge – Product Manager ANSYS_Emag 8.0 rev 1.0

2. Physics Classes – ANSYS Terminology
Current conduction
Electrostatic
Quasi-static electromagnetic
Circuit Coupling
Full Wave Electromagnetic
Magnetostatic
Physics Coupling
LF Emag
Modal, Frequency
& Time Domain
HF Emag
Modal & Frequency Domain
MULTIPHYSICS

3. Definition of LF Electromagnetics
• Low Frequency (LF) electromagnetics is concerned with static or
quasi static electromagnetic field phenomena. i.e.
– Current conduction
– Electrostatics
– Magnetostatics
• LF electromagnetic simulations solve a simplified form of Maxwell’s
equations (no displacement current).
• LF electromagnetics is generally defined as when when the
working wavelength is either, zero (statics) or, is much larger than
the geometric dimensions of structure.
• Current conduction is electron/hole migration within a solid
conductor.

4. Definition of HF Electromagnetics
• The generation & propagation of electromagnetic energy in free
space, & its interaction with dielectric or metallic media.
• The numerical simulation of HF electromagnetics involves solving
Maxwell’s equations for the electric and magnetic vector fields.
• HF radiation propagates in free space, and not via electron
migration within a solid conductor (LF).
• The term HF is misleading, and should be more correctly referred
to as full wave analysis.
• Generally speaking HF simulations are required when the
wavelength is similar or smaller that the geometric dimensions of
the structure.

5. ANSYS Emag Features Summary
• 2D & 3D geometry.
• Electrostatics, magnetostatic.
• Current conduction, Joule heating.
• Eddy currents, induction heating.
• Transient magnetic.
• Built in Circuit Builder: Loads are applied to the model directly from the
circuit schematic.
• Infinite FE and Hybrid Boundary Element Technology.
• Lumped parameter extraction for inductance and capacitance matrices.
• Harmonic Analysis (Linear materials)
• Cyclic symmetry
• Time-Transient Analysis (Linear & Non-linear materials)
• Stranded, Coil and Massive conductors
• Current & voltage fed excitation
• 2-D: Magnetic Vector Potential (MVP) Formulation
• 3-D: Magnetic Vector Potential (MVP) Formulation:
– Limited to non-permeable domains
• 3-D: Edge Flux Formulation:
– Permeable & non-permeable domains

6. Magnetostatics: Magnetron B-Field
Solid model consists of mixed permanent magnet materials of various
polarizations.
Images courtesy of PADT Inc.

7. Magnetron Side view & Paths
Image courtesy of PADT Inc.

8. Magnetic Material Properties
• Magnetic material properties are input via GUI form or via command line.
• Relative permitivitty, permeability, resistivity etc can be constant, isotropic,orthotropic ,or
temperature dependent.
• BH curve can be directly input and graphed.

9. Electrostatics
• Steady state or time transient
• H (1st & 2nd order) and Adaptive 3D P elements
• 2D (triangle, or quadrilateral)
• 3D, brick/hex, tetrahedral, pyramid, wedge
• Shell & Contact (Link) elements
• Infinite element boundary or Trefftz hybrid BEA/FEA approaches
• Electric field contour plots, electrostatic force and capacitance
calculations.
• Multiple dielectrics, isotropic, orthotropic material properties.

10. Electrostatics
Image courtesy of Andreas Hieke, Siemens Microelectronics.

11. Ion Optics

12. Ion Optics
Ion Optics - An important feature for the SEMICON and Analytical
instrument markets:
• Particle tracing is a post processing feature.
• Can trace charged particle in either a electrostatic field or magnetostatic
field or both.
• Particles initial conditions definable are:
– Mass
– Charge
– Starting coordinates (x,y,z)
– Velocity vector (Vx,Vy,Vz)
• Can define 50 particles per run.
• Particle trajectory can be plotted in 2D/3D or listed.
• Space charge effects are not accommodated.
• No relativistic effects (velocity is much smaller than speed of light).

13. Charged Particle in an E-Field

14. Charged Particle in a B-Field

15. Charged Particle in a B-Field

16. Ion Optics Example
Example of a particle trace through homogenous magnetic field, with a
changing electric field. Animation is a composite of static cases

17. Ion Optics Example
Example of a particle trace on a charged particle trace!
PLTRACE command used to slide “visualization particles” along the charged
particle trajectories.

18. Charged Particle Example
• Field Emission Display Array

19. Charged Particle Example
• Field Emission Display Electrode Model

20. Charged Particle Example
• Field Emission Device Mesh using Infinite elements

21. Charged Particle Example
• Electrostic voltage contour & Iso-surface Plots:

22. Charged Particle Example
• Field Emission Display electron trajectories

23. Electromagnetic Contact
Image courtesy of CAD-FEM GmbH.

24. Electromagnetic Contact
Feature:
• Contact for Low Frequency Electromagnetic
• Commands: TARGET169, CONTAC171
• Supports: PLANE13, PLANE53, SOLID96, SOLID5, SOLID98
Benefits:
• This new feature is applicable to 3D magnetic scalar potential (MSP), and
2D magnetic vector potential (MVP).
• A lot easier to use than constraint equations!
Market applications:
• Electric motors
• Alternators
• Inductive ignition system sensors
• Linear Motion Systems
• Non Destructive Testing
• Eddy current braking systems

25. Electromagnetic Contact Example
Example: “In pipe” eddy current based sensor. Sensor slides down pipe
detecting flaw in pipe wall.
B-field contours
Pipe
Sensor

26. Induction Heating

27. Eddy Currents & Induction Heating
• Eddy currents in conductors arise from time varying magnetic fields:
– AC or time transient current flowing in coil or conductor
– Moving magnet/electromagnets
– Incident HF electromagnetic energy
• ANSYS Analysis computes/handles:
– Nonlinear B-H curves
– Hysterisis effects are ignored.
– B-fields
– Induced currents
– Time averaged joule heating
• Moving objects can be addressed by:
– Prescribing motion using conventional velocity effects key option for the elements.
– Physically move the model and re-mesh, morph mesh or use a sliding boundary condition at
object interfaces.
Perform Magnetic or
Electromagnetic
analysis
B fields, induced
currents & joule heating
automatically calculated
Build & Mesh model
Prescribe magnetic
fields, currents.
Prescribe motion if
required
Perform thermal
analysis.
Temperature
rise/distribution
automatically calculated
Keep mesh, switch
element type to
thermal elements
Use time averaged joule
heating results as load

28. Eddy Currents / Induction Heating Example
– Solid model meshed
– Current in coil
– Induced current in plate
– Resultant B-Field

29. Eddy Currents / Induction Heating Example
– Joule heating
– Time averaged joule heating
thermal load
– Resultant temperature

30. Rotating Machines
Image courtesy of CAD-FEM GmbH.

31. Cyclic Symmetry
Feature:
• Cyclic symmetry (periodicity) for Low Frequency Electromagnetics
• Commands: CYCLIC and CYCOPT
• Supports: PLANE13, PLANE53, SOLID96, SOLID5, SOLID98, SOLID117
Benefits:
• This new feature is applicable to 3D magnetic scalar potential (MSP),
magnetic vector potential (MVP) and edge (SOLID117) formulations .
• These commands are also used for cyclic symmetry structural analyses
results greater consistency across physics.
• Reduce FEA problem size & faster solution time by making use of
symmetry.
Market applications:
Primarily rotating electromagnetic machines
• Electric motors
• Alternators
• Inductive ignition system sensors

32. Cyclic Symmetry
Example: 4 pole variable reluctance machine reduced to 90 degree sector:
Bcircumferential

33. Cyclic Symmetry Example

34. Rotating Machine Examples
Images courtesy of CAD-FEM GmbH.

35. Rotating Machine Examples
Flux lines
Torque Density

36. Universal motor
Solid model, flux lines & flux density

37. 38
1hp, 220V, 60Hz, 4 poles, 36 Slots, 44 bars
Circuit model for squirrel cage
Double layer lap winding
Sliding interface
3 Phase Induction motor example

38. Rotating Machine Examples
Mesh, flux lines & Bsum contours

39. Inductive Pickup Transducers
Images courtesy of CAD-FEM GmbH.

40. Generator System Simulation
DC output current vs. generator RPM
Single pole pitch, solid model
DC Output Current
0
20
40
60
80
100
120
0 2000 4000 6000 8000 10000 12000 14000
generator rpm
DC
Output
(amp)
Measured Data FEA Simulated Data
Images courtesy of Delphi Automotive Systems

41. Linear Motion Examples

42. Moving Magnetic Probe Example
2D Axi-symmetric model, here probe velocity is defined with
element “real constant” attributes.
Indicates Magnet polarity
Tube
Centerline
Permeable core
Permanent
Magnets
Velocity
“air”

43. Moving Magnetic Probe Example
Magnetic Flux lines when Velocity is 0.0001 m/s and 0.4 m/s

44. Moving Magnetic Probe Example
Radial Component of B when V = 0.0001 m/s

45. Moving Magnetic Probe Example
Currents flow normal to
plane of model
Eddy Current Density when V = 0.4 m/s

46. Path in airgap
Moving Magnetic Probe Example
Path plot of field in air gap

47. Moving Magnetic Probe Example
2D Axi-symmetric model using true moving object, sliding mesh boundary
Animation of flux lines when V = 0.4 m/s

48. Moving Magnetic Probe Example
2D Axi-symmetric model using true moving object, sliding mesh boundary
Animation Animation of Eddy Current Density when V = 0.4 m/s.

49. Magnetic Levitation Example
Flux lines and levitation coil currents:

50. Current Conduction

51. Coupled Electro-Thermal Example
Current Density Electrical Power Thermal Stress
Geometric size is submicron
Detail of integrated circuit via.
Images courtesy of Atila Mertol, LSI Logic.

52. Sub-Micron Interconnect Reliability
Voids
Images courtesy of Seung Kang, Lucent.
Current Density Electro-Thermal Stress
Simulating the effect of voiding

53. Circuit Coupling

54. Circuit Simulation & Coupling
• >14 types of linear FE circuit elements.
• Couples to stranded and massive conductors in the finite
element domain, 2D & 3D.
• Completely arbitrary circuit arrangements.
• Static, Harmonic and Transient analysis.
• Calculates circuit parameters (V, I, Power).

55. Circuit Simulation & Coupling
The circuit builder: A convenient tool to layout circuits and assign parameters to
the components

56. Circuit Simulation & Coupling

57. Automated Post Processing Calculations
• CMATRIX calculates self and mutual capacitance coefficients between conductors.
• CURR2D calculates current flow in a 2-D conductor.
• EMAGERR calculates the relative error in an electrostatic or electromagnetic field analysis.
• EMF calculates the electromotive force (emf) or voltage drop along a predefined path.
• FLUXV calculates the flux passing through a closed contour.
• FMAGSUM summarizes electromagnetic force calculations on element components.
• FOR2D calculates magnetic forces on a body.
• IMPD calculates the impedance of a coaxial device at a particular reference plane.
• LMATRIX calculates the differential inductance matrix and total flux linkage in each coil for an arbitrary set of
coils.
• MAGSOLV specifies magnetic solution options and initiates the solution for a static analysis.
• MMF calculates magnetomotive force along a path.
• PLF2D generates a contour line plot of equipotentials.
• PMGTRAN summarizes electromagnetic results from a transient analysis.
• POWERH calculates the RMS power loss in a conducting body.
• SENERGY determines the stored magnetic energy or co-energy.
• TORQ2D calculates torque on a body in a magnetic field.
• TORQC2D calculates torque on a body in a magnetic field based on a circular path.
• TORQSUM summarizes electromagnetic Maxwell and Virtual work torque calculations on element components
for 2-D planar problems.

58. Automated Capacitance Calculations
CMATRIX Macro:
• Automated computation of capacitance matrix
• Applicable to any number of conductors
• Computes self and mutual capacitance
• Computes ground and lumped matrices
• Useful for extracting lumped capacitance for use in system level
circuit-simulation
P22
P12
P11

59. CMATRIX Example Output
From Verification example VM120

60. The End!