Electric Motor Design

The title says it all - anybody have experience (usage, implementation, or analysis) on preconditioners for 3D magnetics (vector potential formulation, with or without eddies, with or without circuit connections)?

So far, I haven't come across anything that would actually beat incomplete Cholesky ...

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 ...

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