Yes, the stator contains ferromagnetic elements.
So the
varying magnetic field generated by the commutated rotor can attract the soft ferromagnetic stator poles. This forms a variable reluctance motor similar in operation to the stepper motor but with the coils on the inside (in the rotor / armature) - an inside out topology.
Some toothed rotors of commercial stepper motors are composed entirely of soft ferromagnetic materials without any embedded permanent magnets. This design is used in variable reluctance (VR) stepper motors, where the rotor is typically made of soft steel, iron, ferrite or similar materials with salient teeth that align with the stator's magnetic field to minimize reluctance.
In contrast, permanent magnet (PM) and hybrid stepper motors incorporate permanent magnets in the rotor for higher torque and efficiency.
In a typical Lenz situation, an approaching magnetic field to a stator pole causes a repulsive magnetic field and a receding magnetic field an attractive magnetic field.
Let's call this statement #1.
This is kinda true ...but with two qualifications:
1) the stator pole consists only of a conductive coil.
2) the coil is neither open nor shorted (if the coil is not ideal then it can be shorted).
If the stator coil is ideal and has been shorted in the absence of an external magnetic flux, then your statement must be transformed to:
"The rotor's magnetic pole approaching a stator pole is repelled and a receding magnetic pole is repelled, too"
Let's call this statement #2.
There is a gradual transition between these two behaviors (illustrated by these two statements) that depends on the electric resistance of stator coil's circuit, its inductance and the speed between the rotor's pole and stator's pole.
This action of magnetically inducing energy into the stator windings should cause the rotor to slow to a halt. The fact that it continues to spin and induce a field into the stator windings is evidence that there is an inversion of Lenz at play.
I wouldn't go that far.
The fact that it continues to spin and induce current in the stator windings merely means that the torque of the variable reluctance (VR) motor (described in my 1
st paragraph of this post) is greater than the counter-torque of the pure coil stator (acting as generator), which is abstracted in the Statement #1 with my two qualifications.
In other words: the torque of the variable reluctance (VR) motor overcomes the counter-torque of the the loaded stator / generator.
This counter-torque is created by the Lenz dependent forces acting between the rotor and the loaded stator / generator, as described in the Statement #1. This counter-torque becomes zero in the limit case described by the Statement #2.
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