PSU Assistance

[Neale]

I wouldn't get too hung up on ripple, within reason. Apart from anything else, Leadshine recommend transformer/rectifier/capacitor supplies rather than switchmode. Ripple isn't too good if you are talking audio amplifiers, but motors aren't that fussy. We are already over-driving the motors from a volts point of view and relying on the drivers to "lose" excess volts. The drivers will have internal regulation (must have, given their wide working voltages) so the internal clever electronics are fine. They have current limiting on the motor drive side and while I don't know what kind of frequency they use for the PWM, I doubt if it will worry about a bit of input ripple at a lower frequency. The downside is that linear PSUs are bigger, heavier, and probably cost more than a cheap Chinese SMPS. But the "soft" current limiting might cause fewer problems with peak pulse loads?

[Robin Hewitt]

I don't think the problem is in the motors so much as the breakdown voltage of your H bridges