Electric Motor Design

Hi,

and congrats on the progress! I'm first and foremost an FEA person myself, so my two cents are coming from that perspective:

Regarding the number of time-steps, 2 steps per period of the fastest interesting harmonic is the absolute minimum, as per Nyquist's criterion. Never tested this, but I ...

Hi all!

Anybody have a good reference / approach for computing the first critical bending frequency?

I have been using the Jeffcott rotor approach; however I'm not sure which value to use for the shaft-rotor bending stiffness. Including just the shaft (and using the Wikipedia-level beam bending ...

Simple sensitivity analysis added for ThermalModel , based on adjusting each of the fudge factor .correction_coefficient properties of the nodes and connections in the thermal model.


(Connection) Gap: moving to gap connection : 7.200475 deg C change for Rotor coat average
(Node) Phase winding end ...

Another convenience update: added winding factor (m-phase mmf induced by the winding) plotting under the PolyphaseWindingSpec winding specification class .

Examples below for an integer-slot distributed winding, and fractional-slot concentrated winding with its richer subharmonic-containing ...

Finally implemented a convenience function for plotting the airgap flux density components, as a method of the
MotorModelBase class. So, visualizing the airgap flux density components at time-step number 11 now works like this:

figure(4); clf; hold on; box on;
motor.plot_airgap_flux_density ...

I can only give you an 'it depends' answer to the demagnetization-in-air question: it is indeed possible if the magnet material has a poor-enough demagnetization resistance. After all, demagnetization more or less starts to happen when a part of the magnet material is subjected to a large-enough ...

Hello folks!

Kicking off the discussion with an old yet difficult topic: numerically determining the equivalent circuit of an induction machine. Any approaches that you prefer?

My latest approach is based on defining the dq-transformation for the rotor cage, and then using the standard inductance ...

This is a test post with an image.