Simulation

Field Plots

After pre-processing the magnetic circuit can be evaluated by Field Plots. For that plots with different contents and free selectable rotor position and currents can be created. Also possible are plots with rotor and stator geometries, node chains, mesh and material. All plots can be superposed with free zooming into details. The values of the B-Field in mesh elements at the mouse position are shown in a line below the plots.

Calculations

FEM-Simulations for Cogging Torque + BEMF and Nominal Torque + Inductance are executed according to the entered parameter with control of accuracy, and speed of the calculations. Together with the normally fast calculation of the cogging torque also Expected Values are calculated analytically and give also a fast prediction of the Motor Torque. For the Commutation are constant, sinusoidal or user defined currents allowed. Additionally can parameter for motor length, speed, skewing and winding connection be entered. The impact of the variation of these parameters are presented directly without further FEM calculations. FEM calculation are only performed, if geometries, material data or calculation accuracies have changed.

 

BackEMF without and with skewing of stator poles

 The simulations of the dynamical behavior during start up und stationary operation mode are executed with analytical motor and electronic models using time stepping methods. The phase voltage can be defined as an envelope of a PWM signal. The inductance can also be defined by the user as constant value or can be calculated in co-simulation by FEMAG in dependance of the rotor position.

 The results are presented as curves over rotor position and can also be copied via clipboard to other applications or stored in text files.

Forces

After performed Nominal Torque + Inductance calculations radial and tangential appearing forces can be determined in post-processing routines. These results can be used in other applications to simulate i.e. deformation, vibration or noise.

 

 

Losses

Additionally iron and copper losses can be calculated in dependance of selected materials and currents. The losses are determined in every mesh element in dependance of the induction and its harmonics and then summarized.