Not a motor expert, but just very curious, and would like to learn.
Have a home food blender. Works on regular wall outlet.
Motor has armature windings.
Also has field (stator) windings.
Also has a commutator.
What kind of a motor is this ?
Advantages of a motor like this compared to perhaps a regular ac
induction motor ?
Have never seen a commutator on an ac motor before.
Is there a rectifier hidden somewhere ?
It's called a universal motor , and it will run on either AC or DC . There
are 2 flavors of universal motor , series wired or shunt wired . I don't
remember why each is more desirable for certain tasks .
infinite RPM - there is no "running soeed" - it will keep gaining
speed with no load untill it blows up.
A shunt wound motor has a running speed where the supply voltage and
the CEMF balance out - the motor will draw current as required to
maintain that speed under any load - and if not externally limited it
will burn itself out trying to maintain that speed.
To be more explicit: an AC induction motor runs at a speed determined
by the motor's winding geometry (which is fixed at time of manufacture)
and the frequency of the AC voltage applied. Varying the speed is done
either with mechanical gearboxes *or* a VFD (Variable Frequency Drive).
For small household appliances (drills, blenders, etc.) that desire some
sort of speed variation, an induction motor is impractical: the electronics
required to vary the frequency are more complex (than simply varying the
possible because it has a wound fiels - the polarity of both rotor and
field change together. A permanent magnet motor can NOT run on AC
because the field can't switch polarity - the motor just buzzes.
Universal motors have the brush angle a bit different than straight DC
motors to reduce brush sparking/burning - but they are fundamentally
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