You can find details about both inductance calculation methods (DC and Small signal) in the manual. Go to MotorCAD menu and look at Help > Manual and search for self and mutual inductance calculation.
We will include a frozen permeability capability in future releases for DC method, apparent inductance. For small signal method, it is incremental inductance calculation and would give more information regarding magnetic saturation due to winding currents and permanent magnet.
You can use Maxwell too and Maxwell uses frozen permeability method to calculate the inductance in FEA simulation.