Festo Контроллер двигателя SEC-ST - Manual (Page 14)

Contents and general instructions
XII
Festo SEC−ST−48−6−P01−EN en 0606c
Resonance frequencies
Impressing of a fixed current for the maximum holding torque
of a stepping motor can cause the motor to tend to oscillate.
Since the stepping motor is a synchronous motor, it follows
the set field within very narrow limits. If no load is applied,
the rotor oscillates beyond the targeted step due to the very
low inertia. If excitation of the next step takes place at an
unfavourable time, the system resonates.
The following possibilities exist to reduce the incidence of this
resonance.
ć In practice, one tries to put the start−stop frequency into a
higher area (ca. 200 Hz and higher), since stepping moĆ
tors in the lower frequency areas have more resonance
frequencies.
ć One can combat it by increasing the start−stop frequency
or through lower phase current.
ć Conversion from full−step to half−step or quarter−step opeĆ
ration can also provide help.
ć It is helpful to always operate the motor with its nominal
load. If that is not possible, the phase current should be
reduced.