Intelligent Motion Systems IB S Series, Руководство по эксплуатации

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T h e P o w e r S u p p l y - D r i v e r R e l a t i o n s h i p
The IB series driver is very current efficient as far as the power supply is
concerned. Once the motor has charged one or both windings of the
motor, all the power supply has to do is replace losses in the system. The
charged winding acts as an energy storage in that the current will recirculate
within the bridge, and in and out of each phase reservoir. This results in a
less than expected current draw on the supply.
Stepping motor drivers are designed with the intention that a user’s power
supply output will ramp up to greater or equal to the minimum operating
voltage. The initial current surge is quite substantial and could damage the
driver if the supply is undersized. The output of the power supply could
fall below the operating range of the driver upon a current surge if it is
undersized. This could cause the power supply to start oscillating in and
out of the voltage range of the driver and result in damage to either the
supply, the driver, or both. There are two types of supplies commonly
used, regulated and unregulated, both of which can be switching or linear.
All have their advantages and disadvantages.
R e g u l a t e d v s . U n r e g u l a t e d
An unregulated linear supply is less expensive and more resilient to
current surges, however, the voltage decreases with increasing current
draw. This can cause problems if the voltage drops below the working
range of the drive. Also of concern are the fluctuations in line voltage.
This can cause the unregulated linear supply to be above or below the
anticipated or acceptable voltage.
A regulated supply maintains a stable output voltage, which is good for
high speed performance. They are also not bothered by line fluctuations,
however, they are more expensive. Depending on the current regulation,
a regulated supply may crowbar or current clamp and lead to an oscilla-
tion that may cause damage to the driver and/or power supply. Back
EMF can cause problems for regulated supplies as well. The current
regeneration may be too large for the regulated supply to absorb. This
could lead to an over voltage condition which could damage the output
circuitry of the IB driver.
Non IMS switching power supplies and regulated linear supplies with
over-current protection are not recommended because of their inability to
handle the surge currents inherit in stepping motor systems.
WARNING! Do not connect or disconnect motor or power
leads with power applied!