Power supply question

What kind of quality current does a stepper motor need?

I have a transformator that gives 300VA and 18 Volts and I am trying
to estimate the ripple in order to calculate the capacitor. First I
wanted the ripple to be 2.5% but it makes the capacitor rather big.

My driver is a chopper type build around the L297 and the L298.
Should I take a higer procentage of ripple to keep the kapacitor
smaller (and cheaper)?

Any ideas friends???

Joachim Reif

Gothenburg, Sweden