Electronic – what are the implications of using a 45kW ACS580 ABB VSD on a 22kw induction motor

I don't know the requirements for LTspice. The motor example seems reasonable, but I didn't try to check all of the details.

A slip value of 0.005 would represent a very light load. For the fan of your previous question, the slip at rated load is 0.15. You should run the simulation for various values of slip and plot the results.

Re: Added Figure 9.11

In 9.11(c), 0.5R2/(2-s) is the correct representation of the effect of the torque produced by the backward rotating field. I don't think that the initially posted equivalent circuit is wrong, but the slip terms in that figure have "f" and "b" subscripts that are not explained.

By labeling the stator components "main," figure 9.11 suggests that an auxiliary stator circuit was used for starting, but has been disconnected for the operation condition represented.

You have to understand an induction motor is basically a transformer with an odd rotating secondary. It has all the properties of the transformer.

What beats you here is magnetic saturation. The voltage you may apply to a given transformer primary depends linear on frequency (within the bounds of the used magnetic material). For your motor/transformer, as soon you go below 20Hz, you have to reduce the primary voltage to avoid saturation of the core.

Saturation does exactly this, during one half of the AC cycle the magnetic material cannot "eat" more voltage-time and so the current increases as it wasn't there. That's why you see those spikes. The lower your frequency drops, the longer the time per AC cycle in which the magnetic material is saturated.