Magnetostatic

Outputs of the solution are:

  • Plot: Magnetic Fluxdensity, Magnetic Fieldstrength, Current Density, Vectorpotential, Nodal Force - virtual, Displacement, Error Estimation, 
  • Table: Total Force - virtual, Total Moment - virtual, Total Lorentz Force, RotorBand Torque - stresstensor, RotorBand Force - stresstensor, Vectorpotential on Conductors - Fluxlinkage, Voltage on Coils, Voltage on Circuits, Electrode Voltage, Electrode Current, Current on Circuits, Power on Circuits, Motion Data,
  • NVH Coupling: Forces in time and frequency domain on teeth.
  • 4D Fields:  Force - virtual NodeID Table, Forcedensity - virtual XYZ Table, Lorentz Force NodeID Table.
  • Coupled Thermal: Temperature

Theory

Magnetostatic Analysis

The magnetostatic solutions describe the distribution of static magnetic fields due to magnets and continuous currents. 

The basis equations:
(1)        rot h = j
(2)        div b = 0
(3)        b = µ h
 

Boundary conditions:
(4)        n x h  | Γh = 0
(5)        n * b  | Γe = 0
 

Vectorpotential a:               

(6)        b = rot a

Magnetostatic weak  a-formulation:

(7)            ( µ-1 rot a, rot a’ )Ω
                + (-µ-1 bs, rot a’ ) Ω
                        + (- ja’ ) ΩC
                        = 0, for all a’ element of Ω

Example

Team Problem 20: Static Force Analysis

Video

This example is a test case for electromagnetic analysis software tools. There are measured results available that we will use for comparison of our results.

Point and Cylinder Example

Mesh of a quarter of the geometry.

Point and Cylinder Example

Results

Fluxdensity and Force

The Fluxdensity result is displayed as contourplot.

Fluxdensity of TEAM20

or as vectorplot

Fluxdensity of TEAM20

The force is calculated on every node.

Force Results of TEAM20

The measured reference result for 3000 A is 8,1 N. In Magnetics for NX, using a standards mesh, the result is 8,2 N,